Example #1
0
// UserInfo returns a user.Info interface for the given namespace, service account name and UID
func UserInfo(namespace, name, uid string) user.Info {
	return &user.DefaultInfo{
		Name:   apiserverserviceaccount.MakeUsername(namespace, name),
		UID:    uid,
		Groups: apiserverserviceaccount.MakeGroupNames(namespace, name),
	}
}
Example #2
0
// WithImpersonation is a filter that will inspect and check requests that attempt to change the user.Info for their requests
func WithImpersonation(handler http.Handler, requestContextMapper request.RequestContextMapper, a authorizer.Authorizer) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
		impersonationRequests, err := buildImpersonationRequests(req.Header)
		if err != nil {
			glog.V(4).Infof("%v", err)
			responsewriters.InternalError(w, req, err)
			return
		}
		if len(impersonationRequests) == 0 {
			handler.ServeHTTP(w, req)
			return
		}

		ctx, exists := requestContextMapper.Get(req)
		if !exists {
			responsewriters.InternalError(w, req, errors.New("no context found for request"))
			return
		}
		requestor, exists := request.UserFrom(ctx)
		if !exists {
			responsewriters.InternalError(w, req, errors.New("no user found for request"))
			return
		}

		// if groups are not specified, then we need to look them up differently depending on the type of user
		// if they are specified, then they are the authority
		groupsSpecified := len(req.Header[authenticationapi.ImpersonateGroupHeader]) > 0

		// make sure we're allowed to impersonate each thing we're requesting.  While we're iterating through, start building username
		// and group information
		username := ""
		groups := []string{}
		userExtra := map[string][]string{}
		for _, impersonationRequest := range impersonationRequests {
			actingAsAttributes := &authorizer.AttributesRecord{
				User:            requestor,
				Verb:            "impersonate",
				APIGroup:        impersonationRequest.GetObjectKind().GroupVersionKind().Group,
				Namespace:       impersonationRequest.Namespace,
				Name:            impersonationRequest.Name,
				ResourceRequest: true,
			}

			switch impersonationRequest.GetObjectKind().GroupVersionKind().GroupKind() {
			case api.Kind("ServiceAccount"):
				actingAsAttributes.Resource = "serviceaccounts"
				username = serviceaccount.MakeUsername(impersonationRequest.Namespace, impersonationRequest.Name)
				if !groupsSpecified {
					// if groups aren't specified for a service account, we know the groups because its a fixed mapping.  Add them
					groups = serviceaccount.MakeGroupNames(impersonationRequest.Namespace, impersonationRequest.Name)
				}

			case api.Kind("User"):
				actingAsAttributes.Resource = "users"
				username = impersonationRequest.Name

			case api.Kind("Group"):
				actingAsAttributes.Resource = "groups"
				groups = append(groups, impersonationRequest.Name)

			case authenticationapi.Kind("UserExtra"):
				extraKey := impersonationRequest.FieldPath
				extraValue := impersonationRequest.Name
				actingAsAttributes.Resource = "userextras"
				actingAsAttributes.Subresource = extraKey
				userExtra[extraKey] = append(userExtra[extraKey], extraValue)

			default:
				glog.V(4).Infof("unknown impersonation request type: %v", impersonationRequest)
				responsewriters.Forbidden(actingAsAttributes, w, req, fmt.Sprintf("unknown impersonation request type: %v", impersonationRequest))
				return
			}

			allowed, reason, err := a.Authorize(actingAsAttributes)
			if err != nil || !allowed {
				glog.V(4).Infof("Forbidden: %#v, Reason: %s, Error: %v", req.RequestURI, reason, err)
				responsewriters.Forbidden(actingAsAttributes, w, req, reason)
				return
			}
		}

		newUser := &user.DefaultInfo{
			Name:   username,
			Groups: groups,
			Extra:  userExtra,
		}
		requestContextMapper.Update(req, request.WithUser(ctx, newUser))

		oldUser, _ := request.UserFrom(ctx)
		httplog.LogOf(req, w).Addf("%v is acting as %v", oldUser, newUser)

		// clear all the impersonation headers from the request
		req.Header.Del(authenticationapi.ImpersonateUserHeader)
		req.Header.Del(authenticationapi.ImpersonateGroupHeader)
		for headerName := range req.Header {
			if strings.HasPrefix(headerName, authenticationapi.ImpersonateUserExtraHeaderPrefix) {
				req.Header.Del(headerName)
			}
		}

		handler.ServeHTTP(w, req)
	})
}