diff options
-rw-r--r-- | libpod/container_api.go | 8 | ||||
-rw-r--r-- | libpod/container_internal.go | 56 | ||||
-rw-r--r-- | libpod/container_internal_linux.go | 44 | ||||
-rw-r--r-- | pkg/lookup/lookup.go | 156 |
4 files changed, 201 insertions, 63 deletions
diff --git a/libpod/container_api.go b/libpod/container_api.go index e522038a3..30c67eb2a 100644 --- a/libpod/container_api.go +++ b/libpod/container_api.go @@ -10,8 +10,8 @@ import ( "time" "github.com/containers/libpod/libpod/driver" - "github.com/containers/libpod/pkg/chrootuser" "github.com/containers/libpod/pkg/inspect" + "github.com/containers/libpod/pkg/lookup" "github.com/containers/storage/pkg/stringid" "github.com/docker/docker/daemon/caps" "github.com/pkg/errors" @@ -292,13 +292,13 @@ func (c *Container) Exec(tty, privileged bool, env, cmd []string, user string) e // the host hostUser := "" if user != "" { - uid, gid, err := chrootuser.GetUser(c.state.Mountpoint, user) + execUser, err := lookup.GetUserGroupInfo(c.state.Mountpoint, user, nil) if err != nil { - return errors.Wrapf(err, "error getting user to launch exec session as") + return err } // runc expects user formatted as uid:gid - hostUser = fmt.Sprintf("%d:%d", uid, gid) + hostUser = fmt.Sprintf("%d:%d", execUser.Uid, execUser.Gid) } // Generate exec session ID diff --git a/libpod/container_internal.go b/libpod/container_internal.go index 2af216358..d928c4aed 100644 --- a/libpod/container_internal.go +++ b/libpod/container_internal.go @@ -5,6 +5,7 @@ import ( "context" "encoding/json" "fmt" + "github.com/opencontainers/runc/libcontainer/user" "io" "io/ioutil" "os" @@ -14,9 +15,9 @@ import ( "syscall" "github.com/containers/buildah/imagebuildah" - "github.com/containers/libpod/pkg/chrootuser" "github.com/containers/libpod/pkg/hooks" "github.com/containers/libpod/pkg/hooks/exec" + "github.com/containers/libpod/pkg/lookup" "github.com/containers/libpod/pkg/resolvconf" "github.com/containers/libpod/pkg/rootless" "github.com/containers/libpod/pkg/secrets" @@ -1029,7 +1030,8 @@ func (c *Container) writeStringToRundir(destFile, output string) (string, error) func (c *Container) generatePasswd() (string, error) { var ( groupspec string - gid uint32 + group *user.Group + gid int ) if c.config.User == "" { return "", nil @@ -1044,21 +1046,27 @@ func (c *Container) generatePasswd() (string, error) { if err != nil { return "", nil } - // if UID exists inside of container rootfs /etc/passwd then - // don't generate passwd - if _, _, err := chrootuser.LookupUIDInContainer(c.state.Mountpoint, uid); err == nil { + // Lookup the user to see if it exists in the container image + _, err = lookup.GetUser(c.state.Mountpoint, userspec) + if err != nil && err != user.ErrNoPasswdEntries { + return "", err + } + if err == nil { return "", nil } - if err == nil && groupspec != "" { + if groupspec != "" { if !c.state.Mounted { return "", errors.Wrapf(ErrCtrStateInvalid, "container %s must be mounted in order to translate group field for passwd record", c.ID()) } - gid, err = chrootuser.GetGroup(c.state.Mountpoint, groupspec) + group, err = lookup.GetGroup(c.state.Mountpoint, groupspec) if err != nil { - return "", errors.Wrapf(err, "unable to get gid from %s formporary passwd file") + if err == user.ErrNoGroupEntries { + return "", errors.Wrapf(err, "unable to get gid %s from group file", groupspec) + } + return "", err } + gid = group.Gid } - originPasswdFile := filepath.Join(c.state.Mountpoint, "/etc/passwd") orig, err := ioutil.ReadFile(originPasswdFile) if err != nil { @@ -1153,6 +1161,7 @@ func (c *Container) generateHosts() (string, error) { } func (c *Container) addLocalVolumes(ctx context.Context, g *generate.Generator) error { + var uid, gid int mountPoint := c.state.Mountpoint if !c.state.Mounted { return errors.Wrapf(ErrInternal, "container is not mounted") @@ -1176,6 +1185,18 @@ func (c *Container) addLocalVolumes(ctx context.Context, g *generate.Generator) } } + if c.config.User != "" { + if !c.state.Mounted { + return errors.Wrapf(ErrCtrStateInvalid, "container %s must be mounted in order to translate User field", c.ID()) + } + execUser, err := lookup.GetUserGroupInfo(c.state.Mountpoint, c.config.User, nil) + if err != nil { + return err + } + uid = execUser.Uid + gid = execUser.Gid + } + for k := range imageData.ContainerConfig.Volumes { mount := spec.Mount{ Destination: k, @@ -1186,19 +1207,6 @@ func (c *Container) addLocalVolumes(ctx context.Context, g *generate.Generator) continue } volumePath := filepath.Join(c.config.StaticDir, "volumes", k) - var ( - uid uint32 - gid uint32 - ) - if c.config.User != "" { - if !c.state.Mounted { - return errors.Wrapf(ErrCtrStateInvalid, "container %s must be mounted in order to translate User field", c.ID()) - } - uid, gid, err = chrootuser.GetUser(c.state.Mountpoint, c.config.User) - if err != nil { - return err - } - } // Ensure the symlinks are resolved resolvedSymlink, err := imagebuildah.ResolveSymLink(mountPoint, k) @@ -1218,7 +1226,7 @@ func (c *Container) addLocalVolumes(ctx context.Context, g *generate.Generator) return errors.Wrapf(err, "error creating directory %q for volume %q in container %q", volumePath, k, c.ID()) } - if err = os.Chown(srcPath, int(uid), int(gid)); err != nil { + if err = os.Chown(srcPath, uid, gid); err != nil { return errors.Wrapf(err, "error chowning directory %q for volume %q in container %q", srcPath, k, c.ID()) } } @@ -1228,7 +1236,7 @@ func (c *Container) addLocalVolumes(ctx context.Context, g *generate.Generator) return errors.Wrapf(err, "error creating directory %q for volume %q in container %q", volumePath, k, c.ID()) } - if err = os.Chown(volumePath, int(uid), int(gid)); err != nil { + if err = os.Chown(volumePath, uid, gid); err != nil { return errors.Wrapf(err, "error chowning directory %q for volume %q in container %q", volumePath, k, c.ID()) } diff --git a/libpod/container_internal_linux.go b/libpod/container_internal_linux.go index 0a1784ba7..7bf2c71ca 100644 --- a/libpod/container_internal_linux.go +++ b/libpod/container_internal_linux.go @@ -19,12 +19,10 @@ import ( cnitypes "github.com/containernetworking/cni/pkg/types/current" "github.com/containernetworking/plugins/pkg/ns" crioAnnotations "github.com/containers/libpod/pkg/annotations" - "github.com/containers/libpod/pkg/chrootuser" "github.com/containers/libpod/pkg/criu" + "github.com/containers/libpod/pkg/lookup" "github.com/containers/libpod/pkg/rootless" "github.com/containers/storage/pkg/idtools" - "github.com/cyphar/filepath-securejoin" - "github.com/opencontainers/runc/libcontainer/user" spec "github.com/opencontainers/runtime-spec/specs-go" "github.com/opencontainers/runtime-tools/generate" "github.com/opencontainers/selinux/go-selinux/label" @@ -135,6 +133,10 @@ func (c *Container) cleanupNetwork() error { // Generate spec for a container // Accepts a map of the container's dependencies func (c *Container) generateSpec(ctx context.Context) (*spec.Spec, error) { + execUser, err := lookup.GetUserGroupInfo(c.state.Mountpoint, c.config.User, nil) + if err != nil { + return nil, err + } g := generate.NewFromSpec(c.config.Spec) // If network namespace was requested, add it now @@ -188,7 +190,6 @@ func (c *Container) generateSpec(ctx context.Context) (*spec.Spec, error) { } } - var err error if !rootless.IsRootless() { if c.state.ExtensionStageHooks, err = c.setupOCIHooks(ctx, g.Config); err != nil { return nil, errors.Wrapf(err, "error setting up OCI Hooks") @@ -206,13 +207,9 @@ func (c *Container) generateSpec(ctx context.Context) (*spec.Spec, error) { if !c.state.Mounted { return nil, errors.Wrapf(ErrCtrStateInvalid, "container %s must be mounted in order to translate User field", c.ID()) } - uid, gid, err := chrootuser.GetUser(c.state.Mountpoint, c.config.User) - if err != nil { - return nil, err - } // User and Group must go together - g.SetProcessUID(uid) - g.SetProcessGID(gid) + g.SetProcessUID(uint32(execUser.Uid)) + g.SetProcessGID(uint32(execUser.Gid)) } // Add addition groups if c.config.GroupAdd is not empty @@ -220,11 +217,8 @@ func (c *Container) generateSpec(ctx context.Context) (*spec.Spec, error) { if !c.state.Mounted { return nil, errors.Wrapf(ErrCtrStateInvalid, "container %s must be mounted in order to add additional groups", c.ID()) } - for _, group := range c.config.Groups { - gid, err := chrootuser.GetGroup(c.state.Mountpoint, group) - if err != nil { - return nil, err - } + gids, _ := lookup.GetContainerGroups(c.config.Groups, c.state.Mountpoint, nil) + for _, gid := range gids { g.AddProcessAdditionalGid(gid) } } @@ -237,26 +231,6 @@ func (c *Container) generateSpec(ctx context.Context) (*spec.Spec, error) { // Look up and add groups the user belongs to, if a group wasn't directly specified if !rootless.IsRootless() && !strings.Contains(c.config.User, ":") { - var groupDest, passwdDest string - defaultExecUser := user.ExecUser{ - Uid: 0, - Gid: 0, - Home: "/", - } - - // Make sure the /etc/group and /etc/passwd destinations are not a symlink to something naughty - if groupDest, err = securejoin.SecureJoin(c.state.Mountpoint, "/etc/group"); err != nil { - logrus.Debug(err) - return nil, err - } - if passwdDest, err = securejoin.SecureJoin(c.state.Mountpoint, "/etc/passwd"); err != nil { - logrus.Debug(err) - return nil, err - } - execUser, err := user.GetExecUserPath(c.config.User, &defaultExecUser, passwdDest, groupDest) - if err != nil { - return nil, err - } for _, gid := range execUser.Sgids { g.AddProcessAdditionalGid(uint32(gid)) } diff --git a/pkg/lookup/lookup.go b/pkg/lookup/lookup.go new file mode 100644 index 000000000..b27e2a724 --- /dev/null +++ b/pkg/lookup/lookup.go @@ -0,0 +1,156 @@ +package lookup + +import ( + "github.com/cyphar/filepath-securejoin" + "github.com/opencontainers/runc/libcontainer/user" + "github.com/sirupsen/logrus" + "strconv" +) + +const ( + etcpasswd = "/etc/passwd" + etcgroup = "/etc/group" +) + +// Overrides allows you to override defaults in GetUserGroupInfo +type Overrides struct { + DefaultUser *user.ExecUser + ContainerEtcPasswdPath string + ContainerEtcGroupPath string +} + +// GetUserGroupInfo takes string forms of the the container's mount path and the container user and +// returns a ExecUser with uid, gid, sgids, and home. And override can be provided for defaults. +func GetUserGroupInfo(containerMount, containerUser string, override *Overrides) (*user.ExecUser, error) { + var ( + passwdDest, groupDest string + defaultExecUser *user.ExecUser + err error + ) + passwdPath := etcpasswd + groupPath := etcgroup + + if override != nil { + // Check for an override /etc/passwd path + if override.ContainerEtcPasswdPath != "" { + passwdPath = override.ContainerEtcPasswdPath + } + // Check for an override for /etc/group path + if override.ContainerEtcGroupPath != "" { + groupPath = override.ContainerEtcGroupPath + } + } + + // Check for an override default user + if override != nil && override.DefaultUser != nil { + defaultExecUser = override.DefaultUser + } else { + // Define a default container user + //defaultExecUser = &user.ExecUser{ + // Uid: 0, + // Gid: 0, + // Home: "/", + defaultExecUser = nil + + } + + // Make sure the /etc/group and /etc/passwd destinations are not a symlink to something naughty + if passwdDest, err = securejoin.SecureJoin(containerMount, passwdPath); err != nil { + logrus.Debug(err) + return nil, err + } + if groupDest, err = securejoin.SecureJoin(containerMount, groupPath); err != nil { + logrus.Debug(err) + return nil, err + } + return user.GetExecUserPath(containerUser, defaultExecUser, passwdDest, groupDest) +} + +// GetContainerGroups uses securejoin to get a list of numerical groupids from a container. Per the runc +// function it calls: If a group name cannot be found, an error will be returned. If a group id cannot be found, +// or the given group data is nil, the id will be returned as-is provided it is in the legal range. +func GetContainerGroups(groups []string, containerMount string, override *Overrides) ([]uint32, error) { + var ( + groupDest string + err error + uintgids []uint32 + ) + + groupPath := etcgroup + if override != nil && override.ContainerEtcGroupPath != "" { + groupPath = override.ContainerEtcGroupPath + } + + if groupDest, err = securejoin.SecureJoin(containerMount, groupPath); err != nil { + logrus.Debug(err) + return nil, err + } + + gids, err := user.GetAdditionalGroupsPath(groups, groupDest) + if err != nil { + return nil, err + } + // For libpod, we want []uint32s + for _, gid := range gids { + uintgids = append(uintgids, uint32(gid)) + } + return uintgids, nil +} + +// GetUser takes a containermount path and user name or id and returns +// a matching User structure from /etc/passwd. If it cannot locate a user +// with the provided information, an ErrNoPasswdEntries is returned. +func GetUser(containerMount, userIDorName string) (*user.User, error) { + var inputIsName bool + uid, err := strconv.Atoi(userIDorName) + if err != nil { + inputIsName = true + } + passwdDest, err := securejoin.SecureJoin(containerMount, etcpasswd) + if err != nil { + return nil, err + } + users, err := user.ParsePasswdFileFilter(passwdDest, func(u user.User) bool { + if inputIsName { + return u.Name == userIDorName + } + return u.Uid == uid + }) + if err != nil { + return nil, err + } + if len(users) > 0 { + return &users[0], nil + } + return nil, user.ErrNoPasswdEntries +} + +// GetGroup takes ac ontainermount path and a group name or id and returns +// a match Group struct from /etc/group. if it cannot locate a group, +// an ErrNoGroupEntries error is returned. +func GetGroup(containerMount, groupIDorName string) (*user.Group, error) { + var inputIsName bool + gid, err := strconv.Atoi(groupIDorName) + if err != nil { + inputIsName = true + } + + groupDest, err := securejoin.SecureJoin(containerMount, etcgroup) + if err != nil { + return nil, err + } + + groups, err := user.ParseGroupFileFilter(groupDest, func(g user.Group) bool { + if inputIsName { + return g.Name == groupIDorName + } + return g.Gid == gid + }) + if err != nil { + return nil, err + } + if len(groups) > 0 { + return &groups[0], nil + } + return nil, user.ErrNoGroupEntries +} |