pasta: Allow specifying paths and names of namespaces

Based on a patch from Giuseppe Scrivano, this adds the ability to:

- specify paths and names of target namespaces to join, instead of
  a PID, also for user namespaces, with --userns

- request to join or create a network namespace only, without
  entering or creating a user namespace, with --netns-only

- specify the base directory for netns mountpoints, with --nsrun-dir

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
[sbrivio: reworked logic to actually join the given namespaces when
 they're not created, implemented --netns-only and --nsrun-dir,
 updated pasta demo script and man page]
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/udp.c b/udp.c
index 6b2ee36..0837cba 100644
--- a/udp.c
+++ b/udp.c
@@ -516,7 +516,7 @@ static int udp_splice_connect_ns(void *arg)
 
 	a = (struct udp_splice_connect_ns_arg *)arg;
 
-	ns_enter(a->c->pasta_pid);
+	ns_enter(a->c);
 	a->s = udp_splice_connect(a->c, a->v6, a->bound_sock, a->src, a->dst,
 				  UDP_BACK_TO_INIT);
 
@@ -1004,7 +1004,7 @@ int udp_sock_init_ns(void *arg)
 	struct ctx *c = (struct ctx *)arg;
 	in_port_t dst;
 
-	ns_enter(c->pasta_pid);
+	ns_enter(c);
 
 	for (dst = 0; dst < USHRT_MAX; dst++) {
 		if (!bitmap_isset(c->udp.port_to_init, dst))