From 2a961a711312375273aa17f784d795b9c13b9e6e Mon Sep 17 00:00:00 2001 From: Divyansh Kamboj Date: Sun, 21 Apr 2019 16:22:50 +0530 Subject: Add unshare to podman This command lets the user run a command in a new user namespace like `unshare -u`. It uses the implementation of unshare in buildah. ( fixes #1388 ) Signed-off-by: Divyansh Kamboj --- cmd/podman/unshare.go | 54 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) create mode 100644 cmd/podman/unshare.go (limited to 'cmd/podman/unshare.go') diff --git a/cmd/podman/unshare.go b/cmd/podman/unshare.go new file mode 100644 index 000000000..1db647dba --- /dev/null +++ b/cmd/podman/unshare.go @@ -0,0 +1,54 @@ +// +build linux + +package main + +import ( + "os" + "os/exec" + + "github.com/containers/buildah/pkg/unshare" + "github.com/pkg/errors" + "github.com/spf13/cobra" +) + +var ( + unshareDescription = "Runs a command in a modified user namespace." + _unshareCommand = &cobra.Command{ + Use: "unshare [flags] [COMMAND [ARG]]", + Short: "Run a command in a modified user namespace", + Long: unshareDescription, + RunE: unshareCmd, + Example: `podman unshare id + podman unshare cat /proc/self/uid_map, + podman unshare podman-script.sh`, + } +) + +func init() { + _unshareCommand.SetUsageTemplate(UsageTemplate()) + flags := _unshareCommand.Flags() + flags.SetInterspersed(false) +} + +// unshareCmd execs whatever using the ID mappings that we want to use for ourselves +func unshareCmd(c *cobra.Command, args []string) error { + if isRootless := unshare.IsRootless(); !isRootless { + return errors.Errorf("please use unshare with rootless") + } + // exec the specified command, if there is one + if len(args) < 1 { + // try to exec the shell, if one's set + shell, shellSet := os.LookupEnv("SHELL") + if !shellSet { + return errors.Errorf("no command specified and no $SHELL specified") + } + args = []string{shell} + } + cmd := exec.Command(args[0], args[1:]...) + cmd.Env = unshare.RootlessEnv() + cmd.Stdin = os.Stdin + cmd.Stdout = os.Stdout + cmd.Stderr = os.Stderr + unshare.ExecRunnable(cmd) + return nil +} -- cgit v1.2.3-54-g00ecf