Add support for --chrootdirs

Signed-off-by: LStandman <65296484+LStandman@users.noreply.github.com>

5 files changed, 55 insertions, 4 deletions

diff --git a/libpod/container_config.go b/libpod/container_config.go
index e56f1342a..0d9cd5723 100644
--- a/libpod/container_config.go
+++ b/libpod/container_config.go
@@ -165,6 +165,10 @@ type ContainerRootFSConfig struct {
 	Volatile bool `json:"volatile,omitempty"`
 	// Passwd allows to user to override podman's passwd/group file setup
 	Passwd *bool `json:"passwd,omitempty"`
+	// ChrootDirs is an additional set of directories that need to be
+	// treated as root directories. Standard bind mounts will be mounted
+	// into paths relative to these directories.
+	ChrootDirs []string `json:"chroot_directories,omitempty"`
 }
 
 // ContainerSecurityConfig is an embedded sub-config providing security configuration
diff --git a/libpod/container_inspect.go b/libpod/container_inspect.go
index 3df6203e3..5fb32bd90 100644
--- a/libpod/container_inspect.go
+++ b/libpod/container_inspect.go
@@ -411,6 +411,7 @@ func (c *Container) generateInspectContainerConfig(spec *spec.Spec) *define.Insp
 	}
 
 	ctrConfig.Passwd = c.config.Passwd
+	ctrConfig.ChrootDirs = append(ctrConfig.ChrootDirs, c.config.ChrootDirs...)
 
 	return ctrConfig
 }
diff --git a/libpod/container_internal_linux.go b/libpod/container_internal_linux.go
index 1517a7df7..75250b9b1 100644
--- a/libpod/container_internal_linux.go
+++ b/libpod/container_internal_linux.go
@@ -1811,6 +1811,17 @@ func (c *Container) getRootNetNsDepCtr() (depCtr *Container, err error) {
 	return depCtr, nil
 }
 
+// Ensure standard bind mounts are mounted into all root directories (including chroot directories)
+func (c *Container) mountIntoRootDirs(mountName string, mountPath string) error {
+	c.state.BindMounts[mountName] = mountPath
+
+	for _, chrootDir := range c.config.ChrootDirs {
+		c.state.BindMounts[filepath.Join(chrootDir, mountName)] = mountPath
+	}
+
+	return nil
+}
+
 // Make standard bind mounts to include in the container
 func (c *Container) makeBindMounts() error {
 	if err := os.Chown(c.state.RunDir, c.RootUID(), c.RootGID()); err != nil {
@@ -1864,7 +1875,11 @@ func (c *Container) makeBindMounts() error {
 			// If it doesn't, don't copy them
 			resolvPath, exists := bindMounts["/etc/resolv.conf"]
 			if !c.config.UseImageResolvConf && exists {
-				c.state.BindMounts["/etc/resolv.conf"] = resolvPath
+				err := c.mountIntoRootDirs("/etc/resolv.conf", resolvPath)
+
+				if err != nil {
+					return errors.Wrapf(err, "error assigning mounts to container %s", c.ID())
+				}
 			}
 
 			// check if dependency container has an /etc/hosts file.
@@ -1884,7 +1899,11 @@ func (c *Container) makeBindMounts() error {
 				depCtr.lock.Unlock()
 
 				// finally, save it in the new container
-				c.state.BindMounts["/etc/hosts"] = hostsPath
+				err := c.mountIntoRootDirs("/etc/hosts", hostsPath)
+
+				if err != nil {
+					return errors.Wrapf(err, "error assigning mounts to container %s", c.ID())
+				}
 			}
 
 			if !hasCurrentUserMapped(c) {
@@ -1901,7 +1920,11 @@ func (c *Container) makeBindMounts() error {
 				if err != nil {
 					return errors.Wrapf(err, "error creating resolv.conf for container %s", c.ID())
 				}
-				c.state.BindMounts["/etc/resolv.conf"] = newResolv
+				err = c.mountIntoRootDirs("/etc/resolv.conf", newResolv)
+
+				if err != nil {
+					return errors.Wrapf(err, "error assigning mounts to container %s", c.ID())
+				}
 			}
 
 			if !c.config.UseImageHosts {
@@ -2329,7 +2352,11 @@ func (c *Container) updateHosts(path string) error {
 	if err != nil {
 		return err
 	}
-	c.state.BindMounts["/etc/hosts"] = newHosts
+
+	if err = c.mountIntoRootDirs("/etc/hosts", newHosts); err != nil {
+		return err
+	}
+
 	return nil
 }
 
diff --git a/libpod/define/container_inspect.go b/libpod/define/container_inspect.go
index 804b2b143..ae2ce9724 100644
--- a/libpod/define/container_inspect.go
+++ b/libpod/define/container_inspect.go
@@ -75,6 +75,10 @@ type InspectContainerConfig struct {
 	StopTimeout uint `json:"StopTimeout"`
 	// Passwd determines whether or not podman can add entries to /etc/passwd and /etc/group
 	Passwd *bool `json:"Passwd,omitempty"`
+	// ChrootDirs is an additional set of directories that need to be
+	// treated as root directories. Standard bind mounts will be mounted
+	// into paths relative to these directories.
+	ChrootDirs []string `json:"ChrootDirs,omitempty"`
 }
 
 // InspectRestartPolicy holds information about the container's restart policy.
diff --git a/libpod/options.go b/libpod/options.go
index 1ee4e7322..2e5454393 100644
--- a/libpod/options.go
+++ b/libpod/options.go
@@ -2036,3 +2036,18 @@ func WithVolatile() CtrCreateOption {
 		return nil
 	}
 }
+
+// WithChrootDirs is an additional set of directories that need to be
+// treated as root directories. Standard bind mounts will be mounted
+// into paths relative to these directories.
+func WithChrootDirs(dirs []string) CtrCreateOption {
+	return func(ctr *Container) error {
+		if ctr.valid {
+			return define.ErrCtrFinalized
+		}
+
+		ctr.config.ChrootDirs = dirs
+
+		return nil
+	}
+}