Allow rootless users to use the cache directory in homedir

Currently rootless podman attempts to write to /var/lib/containers/cache
and fails. This causes us to repeatedly push images that have already been
pushed.  This cache directory should be relative to the location of containers/storage
and not always stored in the same directory.

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

Closes: #1411
Approved by: TomSweeneyRedHat

buildah.go

@@ -336,10 +336,10 @@ type BuilderOptions struct {
 	// needs to be pulled and the image name alone can not be resolved to a
 	// reference to a source image.  No separator is implicitly added.
 	Registry string
-	// PullBlobDirectory is the name of a directory in which we'll attempt
+	// BlobDirectory is the name of a directory in which we'll attempt
 	// to store copies of layer blobs that we pull down, if any.  It should
 	// already exist.
-	PullBlobDirectory string
+	BlobDirectory string
 	// Mount signals to NewBuilder() that the container should be mounted
 	// immediately.
 	Mount bool

cmd/buildah/bud.go

@@ -183,6 +183,11 @@ func budCmd(c *cobra.Command, inputArgs []string, iopts budResults) error {
 	if err != nil {
 		return errors.Wrapf(err, "error building system context")
 	}
+	if iopts.BlobCache != "" {
+		systemContext.BlobInfoCacheDir = iopts.BlobCache
+	} else {
+		systemContext.BlobInfoCacheDir = filepath.Join(store.GraphRoot(), "cache")
+	}
 
 	isolation, err := parse.IsolationOption(c)
 	if err != nil {

cmd/buildah/commit.go

@@ -156,6 +156,7 @@ func commitCmd(c *cobra.Command, args []string, iopts commitInputOptions) error
 		Squash:                iopts.squash,
 		BlobDirectory:         iopts.blobCache,
 		OmitTimestamp:         iopts.omitTimestamp,
+		Store:                 store,
 	}
 	if !iopts.quiet {
 		options.ReportWriter = os.Stderr

cmd/buildah/from.go

@@ -226,7 +226,7 @@ func fromCmd(c *cobra.Command, args []string, iopts fromReply) error {
 		DropCapabilities:      iopts.CapDrop,
 		CommonBuildOpts:       commonOpts,
 		Format:                format,
-		PullBlobDirectory:     iopts.BlobCache,
+		BlobDirectory:         iopts.BlobCache,
 	}
 
 	if !iopts.quiet {

commit.go

@@ -71,6 +71,9 @@ type CommitOptions struct {
 	// OmitTimestamp forces epoch 0 as created timestamp to allow for
 	// deterministic, content-addressable builds.
 	OmitTimestamp bool
+
+	// Store is the local storage store which holds the source image.
+	Store storage.Store
 }
 
 // PushOptions can be used to alter how an image is copied somewhere.
@@ -114,7 +117,7 @@ type PushOptions struct {
 func (b *Builder) Commit(ctx context.Context, dest types.ImageReference, options CommitOptions) (string, reference.Canonical, digest.Digest, error) {
 	var imgID string
 
-	systemContext := getSystemContext(options.SystemContext, options.SignaturePolicyPath)
+	systemContext := getSystemContext(options.Store, options.SystemContext, options.SignaturePolicyPath)
 
 	blocked, err := isReferenceBlocked(dest, systemContext)
 	if err != nil {
@@ -178,7 +181,7 @@ func (b *Builder) Commit(ctx context.Context, dest types.ImageReference, options
 		systemContext.DirForceCompress = true
 	}
 	var manifestBytes []byte
-	if manifestBytes, err = cp.Image(ctx, policyContext, maybeCachedDest, maybeCachedSrc, getCopyOptions(options.ReportWriter, maybeCachedSrc, nil, maybeCachedDest, systemContext, "")); err != nil {
+	if manifestBytes, err = cp.Image(ctx, policyContext, maybeCachedDest, maybeCachedSrc, getCopyOptions(options.Store, options.ReportWriter, maybeCachedSrc, nil, maybeCachedDest, systemContext, "")); err != nil {
 		return imgID, nil, "", errors.Wrapf(err, "error copying layers and metadata for container %q", b.ContainerID)
 	}
 	if len(options.AdditionalTags) > 0 {
@@ -230,7 +233,7 @@ func (b *Builder) Commit(ctx context.Context, dest types.ImageReference, options
 
 // Push copies the contents of the image to a new location.
 func Push(ctx context.Context, image string, dest types.ImageReference, options PushOptions) (reference.Canonical, digest.Digest, error) {
-	systemContext := getSystemContext(options.SystemContext, options.SignaturePolicyPath)
+	systemContext := getSystemContext(options.Store, options.SystemContext, options.SignaturePolicyPath)
 
 	if options.Quiet {
 		options.ReportWriter = nil // Turns off logging output
@@ -266,6 +269,7 @@ func Push(ctx context.Context, image string, dest types.ImageReference, options
 		if err != nil {
 			return nil, "", errors.Wrapf(err, "error wrapping image reference %q in blob cache at %q", transports.ImageName(src), options.BlobDirectory)
 		}
+		systemContext.BlobInfoCacheDir = options.BlobDirectory
 		maybeCachedSrc = cache
 	}
 	// Copy everything.
@@ -276,7 +280,7 @@ func Push(ctx context.Context, image string, dest types.ImageReference, options
 		systemContext.DirForceCompress = true
 	}
 	var manifestBytes []byte
-	if manifestBytes, err = cp.Image(ctx, policyContext, dest, maybeCachedSrc, getCopyOptions(options.ReportWriter, maybeCachedSrc, nil, dest, systemContext, options.ManifestType)); err != nil {
+	if manifestBytes, err = cp.Image(ctx, policyContext, dest, maybeCachedSrc, getCopyOptions(options.Store, options.ReportWriter, maybeCachedSrc, nil, dest, systemContext, options.ManifestType)); err != nil {
 		return nil, "", errors.Wrapf(err, "error copying layers and metadata from %q to %q", transports.ImageName(maybeCachedSrc), transports.ImageName(dest))
 	}
 	if options.ReportWriter != nil {

common.go

@@ -8,6 +8,7 @@ import (
 	cp "github.com/containers/image/copy"
 	"github.com/containers/image/types"
 	"github.com/containers/libpod/pkg/rootless"
+	"github.com/containers/storage"
 )
 
 const (
@@ -17,31 +18,15 @@ const (
 	DOCKER = "docker"
 )
 
-// userRegistriesFile is the path to the per user registry configuration file.
-var userRegistriesFile = filepath.Join(os.Getenv("HOME"), ".config/containers/registries.conf")
-
-func getCopyOptions(reportWriter io.Writer, sourceReference types.ImageReference, sourceSystemContext *types.SystemContext, destinationReference types.ImageReference, destinationSystemContext *types.SystemContext, manifestType string) *cp.Options {
-	sourceCtx := &types.SystemContext{}
+func getCopyOptions(store storage.Store, reportWriter io.Writer, sourceReference types.ImageReference, sourceSystemContext *types.SystemContext, destinationReference types.ImageReference, destinationSystemContext *types.SystemContext, manifestType string) *cp.Options {
+	sourceCtx := getSystemContext(store, nil, "")
 	if sourceSystemContext != nil {
 		*sourceCtx = *sourceSystemContext
-	} else {
-		if rootless.IsRootless() {
-			if _, err := os.Stat(userRegistriesFile); err == nil {
-				sourceCtx.SystemRegistriesConfPath = userRegistriesFile
-			}
-
-		}
 	}
 
-	destinationCtx := &types.SystemContext{}
+	destinationCtx := getSystemContext(store, nil, "")
 	if destinationSystemContext != nil {
 		*destinationCtx = *destinationSystemContext
-	} else {
-		if rootless.IsRootless() {
-			if _, err := os.Stat(userRegistriesFile); err == nil {
-				destinationCtx.SystemRegistriesConfPath = userRegistriesFile
-			}
-		}
 	}
 
 	return &cp.Options{
@@ -52,7 +37,7 @@ func getCopyOptions(reportWriter io.Writer, sourceReference types.ImageReference
 	}
 }
 
-func getSystemContext(defaults *types.SystemContext, signaturePolicyPath string) *types.SystemContext {
+func getSystemContext(store storage.Store, defaults *types.SystemContext, signaturePolicyPath string) *types.SystemContext {
 	sc := &types.SystemContext{}
 	if defaults != nil {
 		*sc = *defaults
@@ -60,11 +45,16 @@ func getSystemContext(defaults *types.SystemContext, signaturePolicyPath string)
 	if signaturePolicyPath != "" {
 		sc.SignaturePolicyPath = signaturePolicyPath
 	}
-	if sc.SystemRegistriesConfPath == "" && rootless.IsRootless() {
-		if _, err := os.Stat(userRegistriesFile); err == nil {
-			sc.SystemRegistriesConfPath = userRegistriesFile
+	if store != nil {
+		if sc.BlobInfoCacheDir == "" {
+			sc.BlobInfoCacheDir = filepath.Join(store.GraphRoot(), "cache")
+		}
+		if sc.SystemRegistriesConfPath == "" && rootless.IsRootless() {
+			userRegistriesFile := filepath.Join(store.GraphRoot(), "registries.conf")
+			if _, err := os.Stat(userRegistriesFile); err == nil {
+				sc.SystemRegistriesConfPath = userRegistriesFile
+			}
 		}
-
 	}
 	return sc
 }

imagebuildah/build.go

@@ -666,7 +666,7 @@ func (b *Executor) Prepare(ctx context.Context, stage imagebuilder.Stage, from s
 		FromImage:             from,
 		PullPolicy:            b.pullPolicy,
 		Registry:              b.registry,
-		PullBlobDirectory:     b.blobDirectory,
+		BlobDirectory:         b.blobDirectory,
 		SignaturePolicyPath:   b.signaturePolicyPath,
 		ReportWriter:          b.reportWriter,
 		SystemContext:         b.systemContext,

import.go

@@ -83,7 +83,7 @@ func importBuilder(ctx context.Context, store storage.Store, options ImportOptio
 		return nil, err
 	}
 
-	systemContext := getSystemContext(&types.SystemContext{}, options.SignaturePolicyPath)
+	systemContext := getSystemContext(store, &types.SystemContext{}, options.SignaturePolicyPath)
 
 	builder, err := importBuilderDataFromImage(ctx, store, systemContext, c.ImageID, options.Container, c.ID)
 	if err != nil {
@@ -115,7 +115,7 @@ func importBuilderFromImage(ctx context.Context, store storage.Store, options Im
 		return nil, errors.Errorf("image name must be specified")
 	}
 
-	systemContext := getSystemContext(options.SystemContext, options.SignaturePolicyPath)
+	systemContext := getSystemContext(store, options.SystemContext, options.SignaturePolicyPath)
 
 	_, img, err := util.FindImage(store, "", systemContext, options.Image)
 	if err != nil {

new.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"math/rand"
+	"path/filepath"
 	"strings"
 
 	"github.com/containers/buildah/util"
@@ -29,7 +30,7 @@ func pullAndFindImage(ctx context.Context, store storage.Store, srcRef types.Ima
 		ReportWriter:  options.ReportWriter,
 		Store:         store,
 		SystemContext: options.SystemContext,
-		BlobDirectory: options.PullBlobDirectory,
+		BlobDirectory: options.BlobDirectory,
 	}
 	ref, err := pullImage(ctx, store, srcRef, pullOptions, sc)
 	if err != nil {
@@ -244,7 +245,12 @@ func newBuilder(ctx context.Context, store storage.Store, options BuilderOptions
 		options.FromImage = ""
 	}
 
-	systemContext := getSystemContext(options.SystemContext, options.SignaturePolicyPath)
+	systemContext := getSystemContext(store, options.SystemContext, options.SignaturePolicyPath)
+	if options.BlobDirectory != "" {
+		systemContext.BlobInfoCacheDir = options.BlobDirectory
+	} else {
+		systemContext.BlobInfoCacheDir = filepath.Join(store.GraphRoot(), "cache")
+	}
 
 	if options.FromImage != "" && options.FromImage != "scratch" {
 		ref, _, img, err = resolveImage(ctx, systemContext, store, options)

pull.go

@@ -4,6 +4,8 @@ import (
 	"context"
 	"fmt"
 	"io"
+	"path/filepath"
+
 	"strings"
 
 	"github.com/containers/buildah/pkg/blobcache"
@@ -153,15 +155,22 @@ func localImageNameForReference(ctx context.Context, store storage.Store, srcRef
 
 // Pull copies the contents of the image from somewhere else to local storage.
 func Pull(ctx context.Context, imageName string, options PullOptions) error {
-	systemContext := getSystemContext(options.SystemContext, options.SignaturePolicyPath)
+	systemContext := getSystemContext(options.Store, options.SystemContext, options.SignaturePolicyPath)
 
 	boptions := BuilderOptions{
 		FromImage:           imageName,
 		SignaturePolicyPath: options.SignaturePolicyPath,
 		SystemContext:       systemContext,
-		PullBlobDirectory:   options.BlobDirectory,
+		BlobDirectory:       options.BlobDirectory,
 		ReportWriter:        options.ReportWriter,
 	}
+	if options.BlobDirectory != "" {
+		systemContext.BlobInfoCacheDir = options.BlobDirectory
+	} else {
+		if systemContext.BlobInfoCacheDir != "" {
+			systemContext.BlobInfoCacheDir = filepath.Join(options.Store.GraphRoot(), "cache")
+		}
+	}
 
 	storageRef, transport, img, err := resolveImage(ctx, systemContext, options.Store, boptions)
 	if err != nil {
@@ -262,7 +271,7 @@ func pullImage(ctx context.Context, store storage.Store, srcRef types.ImageRefer
 	}()
 
 	logrus.Debugf("copying %q to %q", transports.ImageName(srcRef), destName)
-	if _, err := cp.Image(ctx, policyContext, maybeCachedDestRef, srcRef, getCopyOptions(options.ReportWriter, srcRef, sc, maybeCachedDestRef, nil, "")); err != nil {
+	if _, err := cp.Image(ctx, policyContext, maybeCachedDestRef, srcRef, getCopyOptions(store, options.ReportWriter, srcRef, sc, maybeCachedDestRef, nil, "")); err != nil {
 		logrus.Debugf("error copying src image [%q] to dest image [%q] err: %v", transports.ImageName(srcRef), destName, err)
 		return nil, err
 	}