forked from distribution/distribution
-
Notifications
You must be signed in to change notification settings - Fork 0
/
app.go
280 lines (232 loc) · 8.84 KB
/
app.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
package registry
import (
"fmt"
"net/http"
"github.com/docker/distribution/api/v2"
"github.com/docker/distribution/auth"
"github.com/docker/distribution/configuration"
"github.com/docker/distribution/storage"
"github.com/docker/distribution/storagedriver"
"github.com/docker/distribution/storagedriver/factory"
log "github.com/Sirupsen/logrus"
"github.com/gorilla/mux"
)
// App is a global registry application object. Shared resources can be placed
// on this object that will be accessible from all requests. Any writable
// fields should be protected.
type App struct {
Config configuration.Configuration
router *mux.Router
// driver maintains the app global storage driver instance.
driver storagedriver.StorageDriver
// registry is the primary registry backend for the app instance.
registry storage.Registry
layerHandler storage.LayerHandler
accessController auth.AccessController
}
// NewApp takes a configuration and returns a configured app, ready to serve
// requests. The app only implements ServeHTTP and can be wrapped in other
// handlers accordingly.
func NewApp(configuration configuration.Configuration) *App {
app := &App{
Config: configuration,
router: v2.Router(),
}
// Register the handler dispatchers.
app.register(v2.RouteNameBase, func(ctx *Context, r *http.Request) http.Handler {
return http.HandlerFunc(apiBase)
})
app.register(v2.RouteNameManifest, imageManifestDispatcher)
app.register(v2.RouteNameTags, tagsDispatcher)
app.register(v2.RouteNameBlob, layerDispatcher)
app.register(v2.RouteNameBlobUpload, layerUploadDispatcher)
app.register(v2.RouteNameBlobUploadChunk, layerUploadDispatcher)
driver, err := factory.Create(configuration.Storage.Type(), configuration.Storage.Parameters())
if err != nil {
// TODO(stevvooe): Move the creation of a service into a protected
// method, where this is created lazily. Its status can be queried via
// a health check.
panic(err)
}
app.driver = driver
app.registry = storage.NewRegistryWithDriver(app.driver)
authType := configuration.Auth.Type()
if authType != "" {
accessController, err := auth.GetAccessController(configuration.Auth.Type(), configuration.Auth.Parameters())
if err != nil {
panic(fmt.Sprintf("unable to configure authorization (%s): %v", authType, err))
}
app.accessController = accessController
}
layerHandlerType := configuration.LayerHandler.Type()
if layerHandlerType != "" {
lh, err := storage.GetLayerHandler(layerHandlerType, configuration.LayerHandler.Parameters(), driver)
if err != nil {
panic(fmt.Sprintf("unable to configure layer handler (%s): %v", layerHandlerType, err))
}
app.layerHandler = lh
}
return app
}
func (app *App) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// Set a header with the Docker Distribution API Version for all responses.
w.Header().Add("Docker-Distribution-API-Version", "registry/2.0")
app.router.ServeHTTP(w, r)
}
// register a handler with the application, by route name. The handler will be
// passed through the application filters and context will be constructed at
// request time.
func (app *App) register(routeName string, dispatch dispatchFunc) {
// TODO(stevvooe): This odd dispatcher/route registration is by-product of
// some limitations in the gorilla/mux router. We are using it to keep
// routing consistent between the client and server, but we may want to
// replace it with manual routing and structure-based dispatch for better
// control over the request execution.
app.router.GetRoute(routeName).Handler(app.dispatcher(dispatch))
}
// dispatchFunc takes a context and request and returns a constructed handler
// for the route. The dispatcher will use this to dynamically create request
// specific handlers for each endpoint without creating a new router for each
// request.
type dispatchFunc func(ctx *Context, r *http.Request) http.Handler
// TODO(stevvooe): dispatchers should probably have some validation error
// chain with proper error reporting.
// singleStatusResponseWriter only allows the first status to be written to be
// the valid request status. The current use case of this class should be
// factored out.
type singleStatusResponseWriter struct {
http.ResponseWriter
status int
}
func (ssrw *singleStatusResponseWriter) WriteHeader(status int) {
if ssrw.status != 0 {
return
}
ssrw.status = status
ssrw.ResponseWriter.WriteHeader(status)
}
// dispatcher returns a handler that constructs a request specific context and
// handler, using the dispatch factory function.
func (app *App) dispatcher(dispatch dispatchFunc) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
context := app.context(r)
if err := app.authorized(w, r, context, context.vars["name"]); err != nil {
return
}
context.log = log.WithField("name", context.Repository.Name())
handler := dispatch(context, r)
ssrw := &singleStatusResponseWriter{ResponseWriter: w}
context.log.Infoln("handler", resolveHandlerName(r.Method, handler))
handler.ServeHTTP(ssrw, r)
// Automated error response handling here. Handlers may return their
// own errors if they need different behavior (such as range errors
// for layer upload).
if context.Errors.Len() > 0 {
if ssrw.status == 0 {
w.WriteHeader(http.StatusBadRequest)
}
serveJSON(w, context.Errors)
}
})
}
// context constructs the context object for the application. This only be
// called once per request.
func (app *App) context(r *http.Request) *Context {
vars := mux.Vars(r)
context := &Context{
App: app,
urlBuilder: v2.NewURLBuilderFromRequest(r),
}
// Store vars for underlying handlers.
context.vars = vars
return context
}
// authorized checks if the request can proceed with access to the requested
// repository. If it succeeds, the repository will be available on the
// context. An error will be if access is not available.
func (app *App) authorized(w http.ResponseWriter, r *http.Request, context *Context, repo string) error {
if app.accessController == nil {
// No access controller, so we simply provide access.
context.Repository = app.registry.Repository(repo)
return nil // access controller is not enabled.
}
var accessRecords []auth.Access
if repo != "" {
resource := auth.Resource{
Type: "repository",
Name: repo,
}
switch r.Method {
case "GET", "HEAD":
accessRecords = append(accessRecords,
auth.Access{
Resource: resource,
Action: "pull",
})
case "POST", "PUT", "PATCH":
accessRecords = append(accessRecords,
auth.Access{
Resource: resource,
Action: "pull",
},
auth.Access{
Resource: resource,
Action: "push",
})
case "DELETE":
// DELETE access requires full admin rights, which is represented
// as "*". This may not be ideal.
accessRecords = append(accessRecords,
auth.Access{
Resource: resource,
Action: "*",
})
}
} else {
// Only allow the name not to be set on the base route.
route := mux.CurrentRoute(r)
if route == nil || route.GetName() != v2.RouteNameBase {
// For this to be properly secured, context.Name must always be set
// for a resource that may make a modification. The only condition
// under which name is not set and we still allow access is when the
// base route is accessed. This section prevents us from making that
// mistake elsewhere in the code, allowing any operation to proceed.
w.Header().Set("Content-Type", "application/json; charset=utf-8")
w.WriteHeader(http.StatusForbidden)
var errs v2.Errors
errs.Push(v2.ErrorCodeUnauthorized)
serveJSON(w, errs)
}
}
if err := app.accessController.Authorized(r, accessRecords...); err != nil {
switch err := err.(type) {
case auth.Challenge:
w.Header().Set("Content-Type", "application/json; charset=utf-8")
err.ServeHTTP(w, r)
var errs v2.Errors
errs.Push(v2.ErrorCodeUnauthorized, accessRecords)
serveJSON(w, errs)
default:
// This condition is a potential security problem either in
// the configuration or whatever is backing the access
// controller. Just return a bad request with no information
// to avoid exposure. The request should not proceed.
context.log.Errorf("error checking authorization: %v", err)
w.WriteHeader(http.StatusBadRequest)
}
return err
}
// At this point, the request should have access to the repository under
// the requested operation. Make is available on the context.
context.Repository = app.registry.Repository(repo)
return nil
}
// apiBase implements a simple yes-man for doing overall checks against the
// api. This can support auth roundtrips to support docker login.
func apiBase(w http.ResponseWriter, r *http.Request) {
const emptyJSON = "{}"
// Provide a simple /v2/ 200 OK response with empty json response.
w.Header().Set("Content-Type", "application/json; charset=utf-8")
w.Header().Set("Content-Length", fmt.Sprint(len(emptyJSON)))
fmt.Fprint(w, emptyJSON)
}