libpod should know if the network is disabled

/etc/resolv.conf and /etc/hosts should not be created and mounted when the
network is disabled.

We should not be calling the network setup and cleanup functions when it is
disabled either.

In doing this patch, I found that all of the bind mounts were particular to
Linux along with the generate functions, so I moved them to
container_internal_linux.go

Since we are checking if we are using a network namespace, we need to check
after the network namespaces has been created in the spec.

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/cmd/podman/create.go b/cmd/podman/create.go
index 9f6825c95..bcf830c7c 100644
--- a/cmd/podman/create.go
+++ b/cmd/podman/create.go
@@ -670,6 +670,11 @@ func parseCreateOpts(ctx context.Context, c *cli.Context, runtime *libpod.Runtim
 	if util.StringInSlice(".", c.StringSlice("dns-search")) && len(c.StringSlice("dns-search")) > 1 {
 		return nil, errors.Errorf("cannot pass additional search domains when also specifying '.'")
 	}
+	if !netMode.IsPrivate() {
+		if c.IsSet("dns-search") || c.IsSet("dns") || c.IsSet("dns-opt") {
+			return nil, errors.Errorf("specifying DNS flags when network mode is shared with the host or another container is not allowed")
+		}
+	}
 
 	// Validate domains are good
 	for _, dom := range c.StringSlice("dns-search") {