Fix volumes and networks list/prune filters in http api

This is the continuation work started in #9711. It turns out
that list/prune commands for volumes in libpod/compat api have
very dangerous error handling when broken filter input is supplied.
Problem also affects network list/prune in libpod. This commit
unifies filter handling across libpod/compat api and adds sanity
apiv2 testcases.

Signed-off-by: Jakub Guzik <jakubmguzik@gmail.com>

3 files changed, 16 insertions, 91 deletions

diff --git a/pkg/api/handlers/compat/events.go b/pkg/api/handlers/compat/events.go
index 9e82831d7..dd0a9e7a9 100644
--- a/pkg/api/handlers/compat/events.go
+++ b/pkg/api/handlers/compat/events.go
@@ -1,69 +1,19 @@
 package compat
 
 import (
-	"encoding/json"
-	"fmt"
 	"net/http"
 
 	"github.com/containers/podman/v3/libpod"
 	"github.com/containers/podman/v3/libpod/events"
 	"github.com/containers/podman/v3/pkg/api/handlers/utils"
 	"github.com/containers/podman/v3/pkg/domain/entities"
+	"github.com/containers/podman/v3/pkg/util"
 	"github.com/gorilla/schema"
 	jsoniter "github.com/json-iterator/go"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
 
-// filtersFromRequests extracts the "filters" parameter from the specified
-// http.Request.  The parameter can either be a `map[string][]string` as done
-// in new versions of Docker and libpod, or a `map[string]map[string]bool` as
-// done in older versions of Docker.  We have to do a bit of Yoga to support
-// both - just as Docker does as well.
-//
-// Please refer to https://github.com/containers/podman/issues/6899 for some
-// background.
-func filtersFromRequest(r *http.Request) ([]string, error) {
-	var (
-		compatFilters map[string]map[string]bool
-		filters       map[string][]string
-		libpodFilters []string
-		raw           []byte
-	)
-
-	if _, found := r.URL.Query()["filters"]; found {
-		raw = []byte(r.Form.Get("filters"))
-	} else if _, found := r.URL.Query()["Filters"]; found {
-		raw = []byte(r.Form.Get("Filters"))
-	} else {
-		return []string{}, nil
-	}
-
-	// Backwards compat with older versions of Docker.
-	if err := json.Unmarshal(raw, &compatFilters); err == nil {
-		for filterKey, filterMap := range compatFilters {
-			for filterValue, toAdd := range filterMap {
-				if toAdd {
-					libpodFilters = append(libpodFilters, fmt.Sprintf("%s=%s", filterKey, filterValue))
-				}
-			}
-		}
-		return libpodFilters, nil
-	}
-
-	if err := json.Unmarshal(raw, &filters); err != nil {
-		return nil, err
-	}
-
-	for filterKey, filterSlice := range filters {
-		for _, filterValue := range filterSlice {
-			libpodFilters = append(libpodFilters, fmt.Sprintf("%s=%s", filterKey, filterValue))
-		}
-	}
-
-	return libpodFilters, nil
-}
-
 // NOTE: this endpoint serves both the docker-compatible one and the new libpod
 // one.
 func GetEvents(w http.ResponseWriter, r *http.Request) {
@@ -92,7 +42,7 @@ func GetEvents(w http.ResponseWriter, r *http.Request) {
 		fromStart = true
 	}
 
-	libpodFilters, err := filtersFromRequest(r)
+	libpodFilters, err := util.FiltersFromRequest(r)
 	if err != nil {
 		utils.Error(w, "failed to parse parameters", http.StatusBadRequest, errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String()))
 		return
diff --git a/pkg/api/handlers/compat/networks.go b/pkg/api/handlers/compat/networks.go
index 7e06cad66..77ed548d8 100644
--- a/pkg/api/handlers/compat/networks.go
+++ b/pkg/api/handlers/compat/networks.go
@@ -17,6 +17,7 @@ import (
 	"github.com/containers/podman/v3/pkg/domain/entities"
 	"github.com/containers/podman/v3/pkg/domain/infra/abi"
 	networkid "github.com/containers/podman/v3/pkg/network"
+	"github.com/containers/podman/v3/pkg/util"
 	"github.com/docker/docker/api/types"
 	dockerNetwork "github.com/docker/docker/api/types/network"
 	"github.com/gorilla/schema"
@@ -181,18 +182,12 @@ func findPluginByName(plugins []*libcni.NetworkConfig, pluginType string) ([]byt
 
 func ListNetworks(w http.ResponseWriter, r *http.Request) {
 	runtime := r.Context().Value("runtime").(*libpod.Runtime)
-	filters, err := filtersFromRequest(r)
+	filterMap, err := util.PrepareFilters(r)
 	if err != nil {
-		utils.Error(w, "Something went wrong.", http.StatusBadRequest, errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String()))
+		utils.Error(w, "Something went wrong.", http.StatusInternalServerError, errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String()))
 		return
 	}
-	filterMap := map[string][]string{}
-	for _, filter := range filters {
-		split := strings.SplitN(filter, "=", 2)
-		if len(split) > 1 {
-			filterMap[split[0]] = append(filterMap[split[0]], split[1])
-		}
-	}
+
 	config, err := runtime.GetConfig()
 	if err != nil {
 		utils.InternalServerError(w, err)
@@ -208,7 +203,7 @@ func ListNetworks(w http.ResponseWriter, r *http.Request) {
 	reports := []*types.NetworkResource{}
 	logrus.Debugf("netNames: %q", strings.Join(netNames, ", "))
 	for _, name := range netNames {
-		report, err := getNetworkResourceByNameOrID(name, runtime, filterMap)
+		report, err := getNetworkResourceByNameOrID(name, runtime, *filterMap)
 		if err != nil {
 			utils.InternalServerError(w, err)
 			return
@@ -401,22 +396,15 @@ func Disconnect(w http.ResponseWriter, r *http.Request) {
 // Prune removes unused networks
 func Prune(w http.ResponseWriter, r *http.Request) {
 	runtime := r.Context().Value("runtime").(*libpod.Runtime)
-	filters, err := filtersFromRequest(r)
+	filterMap, err := util.PrepareFilters(r)
 	if err != nil {
 		utils.Error(w, "Something went wrong.", http.StatusInternalServerError, errors.Wrap(err, "Decode()"))
 		return
 	}
-	filterMap := map[string][]string{}
-	for _, filter := range filters {
-		split := strings.SplitN(filter, "=", 2)
-		if len(split) > 1 {
-			filterMap[split[0]] = append(filterMap[split[0]], split[1])
-		}
-	}
 
 	ic := abi.ContainerEngine{Libpod: runtime}
 	pruneOptions := entities.NetworkPruneOptions{
-		Filters: filterMap,
+		Filters: *filterMap,
 	}
 	pruneReports, err := ic.NetworkPrune(r.Context(), pruneOptions)
 	if err != nil {
diff --git a/pkg/api/handlers/compat/volumes.go b/pkg/api/handlers/compat/volumes.go
index d2febc615..42ece643b 100644
--- a/pkg/api/handlers/compat/volumes.go
+++ b/pkg/api/handlers/compat/volumes.go
@@ -5,7 +5,6 @@ import (
 	"encoding/json"
 	"net/http"
 	"net/url"
-	"strings"
 	"time"
 
 	"github.com/containers/podman/v3/libpod"
@@ -14,6 +13,7 @@ import (
 	"github.com/containers/podman/v3/pkg/api/handlers/utils"
 	"github.com/containers/podman/v3/pkg/domain/filters"
 	"github.com/containers/podman/v3/pkg/domain/infra/abi/parse"
+	"github.com/containers/podman/v3/pkg/util"
 	docker_api_types "github.com/docker/docker/api/types"
 	docker_api_types_volume "github.com/docker/docker/api/types/volume"
 	"github.com/gorilla/schema"
@@ -22,16 +22,10 @@ import (
 
 func ListVolumes(w http.ResponseWriter, r *http.Request) {
 	var (
-		decoder = r.Context().Value("decoder").(*schema.Decoder)
 		runtime = r.Context().Value("runtime").(*libpod.Runtime)
 	)
-	query := struct {
-		Filters map[string][]string `schema:"filters"`
-	}{
-		// override any golang type defaults
-	}
-
-	if err := decoder.Decode(&query, r.URL.Query()); err != nil {
+	filtersMap, err := util.PrepareFilters(r)
+	if err != nil {
 		utils.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError,
 			errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String()))
 		return
@@ -39,14 +33,14 @@ func ListVolumes(w http.ResponseWriter, r *http.Request) {
 
 	// Reject any libpod specific filters since `GenerateVolumeFilters()` will
 	// happily parse them for us.
-	for filter := range query.Filters {
+	for filter := range *filtersMap {
 		if filter == "opts" {
 			utils.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError,
 				errors.Errorf("unsupported libpod filters passed to docker endpoint"))
 			return
 		}
 	}
-	volumeFilters, err := filters.GenerateVolumeFilters(query.Filters)
+	volumeFilters, err := filters.GenerateVolumeFilters(*filtersMap)
 	if err != nil {
 		utils.InternalServerError(w, err)
 		return
@@ -265,20 +259,13 @@ func PruneVolumes(w http.ResponseWriter, r *http.Request) {
 	var (
 		runtime = r.Context().Value("runtime").(*libpod.Runtime)
 	)
-	filtersList, err := filtersFromRequest(r)
+	filterMap, err := util.PrepareFilters(r)
 	if err != nil {
 		utils.Error(w, "Something went wrong.", http.StatusInternalServerError, errors.Wrap(err, "Decode()"))
 		return
 	}
-	filterMap := map[string][]string{}
-	for _, filter := range filtersList {
-		split := strings.SplitN(filter, "=", 2)
-		if len(split) > 1 {
-			filterMap[split[0]] = append(filterMap[split[0]], split[1])
-		}
-	}
 
-	f := (url.Values)(filterMap)
+	f := (url.Values)(*filterMap)
 	filterFuncs, err := filters.GenerateVolumeFilters(f)
 	if err != nil {
 		utils.Error(w, "Something when wrong.", http.StatusInternalServerError, errors.Wrapf(err, "failed to parse filters for %s", f.Encode()))