Podman Image SCP transfer patch

Fixed syntax so that podman image scp transfer works with no user specified.
This command can only be executed as root so to obtain the default user, I searched for
the SUDO_USER environmental variable. If that is not found, we error out and inform the user
to set this variable and make sure they are running as root

Signed-off-by: cdoern <cdoern@redhat.com>
Signed-off-by: cdoern <cbdoer23@g.holycross.edu>

cmd/podman/images/scp.go

@@ -137,9 +137,15 @@ func scp(cmd *cobra.Command, args []string) (finalErr error) {
 		scpOpts.Save.Format = "oci-archive"
 		abiErr := abiEng.Save(context.Background(), scpOpts.SourceImageName, []string{}, scpOpts.Save) // save the image locally before loading it on remote, local, or ssh
 		if abiErr != nil {
-			errors.Wrapf(abiErr, "could not save image as specified")
+			return errors.Wrapf(abiErr, "could not save image as specified")
 		}
 		if !rootless.IsRootless() && scpOpts.Rootless {
+			if scpOpts.User == "" {
+				scpOpts.User = os.Getenv("SUDO_USER")
+				if scpOpts.User == "" {
+					return errors.New("could not obtain root user, make sure the environmental variable SUDO_USER is set, and that this command is being run as root")
+				}
+			}
 			err := abiEng.Transfer(context.Background(), scpOpts)
 			if err != nil {
 				return err
@@ -274,7 +280,13 @@ func parseArgs(args []string, cfg *config.Config) (map[string]config.Destination
 	cliConnections := []string{}
 	switch len(args) {
 	case 1:
-		if strings.Contains(args[0], "::") {
+		if strings.Contains(args[0], "localhost") {
+			if strings.Split(args[0], "@")[0] != "root" {
+				return nil, errors.Wrapf(define.ErrInvalidArg, "cannot transfer images from any user besides root using sudo")
+			}
+			scpOpts.Rootless = true
+			scpOpts.SourceImageName = strings.Split(args[0], "::")[1]
+		} else if strings.Contains(args[0], "::") {
 			scpOpts.FromRemote = true
 			cliConnections = append(cliConnections, args[0])
 		} else {
@@ -286,11 +298,15 @@ func parseArgs(args []string, cfg *config.Config) (map[string]config.Destination
 		}
 	case 2:
 		if strings.Contains(args[0], "localhost") || strings.Contains(args[1], "localhost") { // only supporting root to local using sudo at the moment
-			scpOpts.Rootless = true
-			scpOpts.User = strings.Split(args[1], "@")[0]
-			scpOpts.SourceImageName = strings.Split(args[0], "::")[1]
 			if strings.Split(args[0], "@")[0] != "root" {
-				return nil, errors.Wrapf(define.ErrInvalidArg, "cannot transfer images from any user besides root using sudo")
+				return nil, errors.Wrapf(define.ErrInvalidArg, "currently, transferring images to a user account is not supported")
+			}
+			if len(strings.Split(args[0], "::")) > 1 {
+				scpOpts.Rootless = true
+				scpOpts.User = strings.Split(args[1], "@")[0]
+				scpOpts.SourceImageName = strings.Split(args[0], "::")[1]
+			} else {
+				return nil, errors.Wrapf(define.ErrInvalidArg, "currently, you cannot rename images during the transfer or transfer them to a user account")
 			}
 		} else if strings.Contains(args[0], "::") {
 			if !(strings.Contains(args[1], "::")) && remoteArgLength(args[0], 1) == 0 { // if an image is specified, this mean we are loading to our client

docs/source/markdown/podman-image-scp.1.md

@@ -68,8 +68,6 @@ Copying blob e2eb06d8af82 done
 Copying config 696d33ca15 done
 Writing manifest to image destination
 Storing signatures
-Run Directory Obtained: /run/user/1000/
-[Run Root: /var/tmp/containers-user-1000/containers Graph Root: /root/.local/share/containers/storage DB Path: /root/.local/share/containers/storage/libpod/bolt_state.db]
 Getting image source signatures
 Copying blob 5eb901baf107 skipped: already exists
 Copying config 696d33ca15 done
@@ -78,6 +76,20 @@ Storing signatures
 Loaded image(s): docker.io/library/alpine:latest
 ```
 
+```
+$ sudo podman image scp root@localhost::alpine
+Copying blob e2eb06d8af82 done
+Copying config 696d33ca15 done
+Writing manifest to image destination
+Storing signatures
+Getting image source signatures
+Copying blob 5eb901baf107
+Copying config 696d33ca15 done
+Writing manifest to image destination
+Storing signatures
+Loaded image(s): docker.io/library/alpine:latest
+```
+
 ## SEE ALSO
 podman(1), podman-load(1), podman-save(1), podman-remote(1), podman-system-connection-add(1), containers.conf(5), containers-transports(5)
 

test/e2e/image_scp_test.go

@@ -78,6 +78,10 @@ var _ = Describe("podman image scp", func() {
 		list.WaitWithDefaultTimeout()
 		Expect(list).To(Exit(0))
 		Expect(list.LineInOutputStartsWith("quay.io/libpod/alpine")).To(BeTrue())
+
+		scp = podmanTest.PodmanAsUser([]string{"image", "scp", "root@localhost::" + ALPINE}, 0, 0, "", env) //transfer from root to rootless (us)
+		scp.WaitWithDefaultTimeout()
+		Expect(scp).To(Exit(0))
 	})
 
 	It("podman image scp bogus image", func() {