diff options
Diffstat (limited to 'vendor/github.com/projectatomic/buildah/util.go')
| -rw-r--r-- | vendor/github.com/projectatomic/buildah/util.go | 182 |
1 files changed, 175 insertions, 7 deletions
diff --git a/vendor/github.com/projectatomic/buildah/util.go b/vendor/github.com/projectatomic/buildah/util.go index 33b5b9e83..0d05aa8a2 100644 --- a/vendor/github.com/projectatomic/buildah/util.go +++ b/vendor/github.com/projectatomic/buildah/util.go @@ -1,15 +1,18 @@ package buildah import ( + "bufio" + "io" + "os" + "strconv" + "strings" + + "github.com/containers/storage/pkg/archive" "github.com/containers/storage/pkg/chrootarchive" + "github.com/containers/storage/pkg/idtools" "github.com/containers/storage/pkg/reexec" -) - -var ( - // CopyWithTar defines the copy method to use. - copyWithTar = chrootarchive.NewArchiver(nil).CopyWithTar - copyFileWithTar = chrootarchive.NewArchiver(nil).CopyFileWithTar - untarPath = chrootarchive.NewArchiver(nil).UntarPath + rspec "github.com/opencontainers/runtime-spec/specs-go" + "github.com/pkg/errors" ) // InitReexec is a wrapper for reexec.Init(). It should be called at @@ -32,3 +35,168 @@ func copyStringSlice(s []string) []string { copy(t, s) return t } + +func stringInSlice(s string, slice []string) bool { + for _, v := range slice { + if v == s { + return true + } + } + return false +} + +func convertStorageIDMaps(UIDMap, GIDMap []idtools.IDMap) ([]rspec.LinuxIDMapping, []rspec.LinuxIDMapping) { + uidmap := make([]rspec.LinuxIDMapping, 0, len(UIDMap)) + gidmap := make([]rspec.LinuxIDMapping, 0, len(GIDMap)) + for _, m := range UIDMap { + uidmap = append(uidmap, rspec.LinuxIDMapping{ + HostID: uint32(m.HostID), + ContainerID: uint32(m.ContainerID), + Size: uint32(m.Size), + }) + } + for _, m := range GIDMap { + gidmap = append(gidmap, rspec.LinuxIDMapping{ + HostID: uint32(m.HostID), + ContainerID: uint32(m.ContainerID), + Size: uint32(m.Size), + }) + } + return uidmap, gidmap +} + +func convertRuntimeIDMaps(UIDMap, GIDMap []rspec.LinuxIDMapping) ([]idtools.IDMap, []idtools.IDMap) { + uidmap := make([]idtools.IDMap, 0, len(UIDMap)) + gidmap := make([]idtools.IDMap, 0, len(GIDMap)) + for _, m := range UIDMap { + uidmap = append(uidmap, idtools.IDMap{ + HostID: int(m.HostID), + ContainerID: int(m.ContainerID), + Size: int(m.Size), + }) + } + for _, m := range GIDMap { + gidmap = append(gidmap, idtools.IDMap{ + HostID: int(m.HostID), + ContainerID: int(m.ContainerID), + Size: int(m.Size), + }) + } + return uidmap, gidmap +} + +// copyFileWithTar returns a function which copies a single file from outside +// of any container into our working container, mapping permissions using the +// container's ID maps, possibly overridden using the passed-in chownOpts +func (b *Builder) copyFileWithTar(chownOpts *idtools.IDPair) func(src, dest string) error { + convertedUIDMap, convertedGIDMap := convertRuntimeIDMaps(b.IDMappingOptions.UIDMap, b.IDMappingOptions.GIDMap) + untarMappings := idtools.NewIDMappingsFromMaps(convertedUIDMap, convertedGIDMap) + archiver := chrootarchive.NewArchiverWithChown(nil, chownOpts, untarMappings) + return archiver.CopyFileWithTar +} + +// copyWithTar returns a function which copies a directory tree from outside of +// any container into our working container, mapping permissions using the +// container's ID maps, possibly overridden using the passed-in chownOpts +func (b *Builder) copyWithTar(chownOpts *idtools.IDPair) func(src, dest string) error { + convertedUIDMap, convertedGIDMap := convertRuntimeIDMaps(b.IDMappingOptions.UIDMap, b.IDMappingOptions.GIDMap) + untarMappings := idtools.NewIDMappingsFromMaps(convertedUIDMap, convertedGIDMap) + archiver := chrootarchive.NewArchiverWithChown(nil, chownOpts, untarMappings) + return archiver.CopyWithTar +} + +// untarPath returns a function which extracts an archive in a specified +// location into our working container, mapping permissions using the +// container's ID maps, possibly overridden using the passed-in chownOpts +func (b *Builder) untarPath(chownOpts *idtools.IDPair) func(src, dest string) error { + convertedUIDMap, convertedGIDMap := convertRuntimeIDMaps(b.IDMappingOptions.UIDMap, b.IDMappingOptions.GIDMap) + untarMappings := idtools.NewIDMappingsFromMaps(convertedUIDMap, convertedGIDMap) + archiver := chrootarchive.NewArchiverWithChown(nil, chownOpts, untarMappings) + return archiver.UntarPath +} + +// tarPath returns a function which creates an archive of a specified +// location in the container's filesystem, mapping permissions using the +// container's ID maps +func (b *Builder) tarPath() func(path string) (io.ReadCloser, error) { + convertedUIDMap, convertedGIDMap := convertRuntimeIDMaps(b.IDMappingOptions.UIDMap, b.IDMappingOptions.GIDMap) + tarMappings := idtools.NewIDMappingsFromMaps(convertedUIDMap, convertedGIDMap) + return func(path string) (io.ReadCloser, error) { + return archive.TarWithOptions(path, &archive.TarOptions{ + Compression: archive.Uncompressed, + UIDMaps: tarMappings.UIDs(), + GIDMaps: tarMappings.GIDs(), + }) + } +} + +// getProcIDMappings reads mappings from the named node under /proc. +func getProcIDMappings(path string) ([]rspec.LinuxIDMapping, error) { + var mappings []rspec.LinuxIDMapping + f, err := os.Open(path) + if err != nil { + return nil, errors.Wrapf(err, "error reading ID mappings from %q", path) + } + defer f.Close() + scanner := bufio.NewScanner(f) + for scanner.Scan() { + line := scanner.Text() + fields := strings.Fields(line) + if len(fields) != 3 { + return nil, errors.Errorf("line %q from %q has %d fields, not 3", line, path, len(fields)) + } + cid, err := strconv.ParseUint(fields[0], 10, 32) + if err != nil { + return nil, errors.Wrapf(err, "error parsing container ID value %q from line %q in %q", fields[0], line, path) + } + hid, err := strconv.ParseUint(fields[1], 10, 32) + if err != nil { + return nil, errors.Wrapf(err, "error parsing host ID value %q from line %q in %q", fields[1], line, path) + } + size, err := strconv.ParseUint(fields[2], 10, 32) + if err != nil { + return nil, errors.Wrapf(err, "error parsing size value %q from line %q in %q", fields[2], line, path) + } + mappings = append(mappings, rspec.LinuxIDMapping{ContainerID: uint32(cid), HostID: uint32(hid), Size: uint32(size)}) + } + return mappings, nil +} + +// getHostIDs uses ID mappings to compute the host-level IDs that will +// correspond to a UID/GID pair in the container. +func getHostIDs(uidmap, gidmap []rspec.LinuxIDMapping, uid, gid uint32) (uint32, uint32, error) { + uidMapped := true + for _, m := range uidmap { + uidMapped = false + if uid >= m.ContainerID && uid < m.ContainerID+m.Size { + uid = (uid - m.ContainerID) + m.HostID + uidMapped = true + break + } + } + if !uidMapped { + return 0, 0, errors.Errorf("container uses ID mappings, but doesn't map UID %d", uid) + } + gidMapped := true + for _, m := range gidmap { + gidMapped = false + if gid >= m.ContainerID && gid < m.ContainerID+m.Size { + gid = (gid - m.ContainerID) + m.HostID + gidMapped = true + break + } + } + if !gidMapped { + return 0, 0, errors.Errorf("container uses ID mappings, but doesn't map GID %d", gid) + } + return uid, gid, nil +} + +// getHostRootIDs uses ID mappings in spec to compute the host-level IDs that will +// correspond to UID/GID 0/0 in the container. +func getHostRootIDs(spec *rspec.Spec) (uint32, uint32, error) { + if spec.Linux == nil { + return 0, 0, nil + } + return getHostIDs(spec.Linux.UIDMappings, spec.Linux.GIDMappings, 0, 0) +} |