selftests/bpf: Move open_netns() and close_netns() into network_helpers.c

These will also be used by the xdp_do_redirect test being added in the next
commit.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220309105346.100053-5-toke@redhat.com
This commit is contained in:
Toke Høiland-Jørgensen 2022-03-09 11:53:45 +01:00 committed by Alexei Starovoitov
parent 24592ad1ab
commit a30338840f
3 changed files with 95 additions and 89 deletions

View file

@ -1,18 +1,25 @@
// SPDX-License-Identifier: GPL-2.0-only
#define _GNU_SOURCE
#include <errno.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sched.h>
#include <arpa/inet.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <linux/err.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/limits.h>
#include "bpf_util.h"
#include "network_helpers.h"
#include "test_progs.h"
#define clean_errno() (errno == 0 ? "None" : strerror(errno))
#define log_err(MSG, ...) ({ \
@ -356,3 +363,82 @@ char *ping_command(int family)
}
return "ping";
}
struct nstoken {
int orig_netns_fd;
};
static int setns_by_fd(int nsfd)
{
int err;
err = setns(nsfd, CLONE_NEWNET);
close(nsfd);
if (!ASSERT_OK(err, "setns"))
return err;
/* Switch /sys to the new namespace so that e.g. /sys/class/net
* reflects the devices in the new namespace.
*/
err = unshare(CLONE_NEWNS);
if (!ASSERT_OK(err, "unshare"))
return err;
/* Make our /sys mount private, so the following umount won't
* trigger the global umount in case it's shared.
*/
err = mount("none", "/sys", NULL, MS_PRIVATE, NULL);
if (!ASSERT_OK(err, "remount private /sys"))
return err;
err = umount2("/sys", MNT_DETACH);
if (!ASSERT_OK(err, "umount2 /sys"))
return err;
err = mount("sysfs", "/sys", "sysfs", 0, NULL);
if (!ASSERT_OK(err, "mount /sys"))
return err;
err = mount("bpffs", "/sys/fs/bpf", "bpf", 0, NULL);
if (!ASSERT_OK(err, "mount /sys/fs/bpf"))
return err;
return 0;
}
struct nstoken *open_netns(const char *name)
{
int nsfd;
char nspath[PATH_MAX];
int err;
struct nstoken *token;
token = malloc(sizeof(struct nstoken));
if (!ASSERT_OK_PTR(token, "malloc token"))
return NULL;
token->orig_netns_fd = open("/proc/self/ns/net", O_RDONLY);
if (!ASSERT_GE(token->orig_netns_fd, 0, "open /proc/self/ns/net"))
goto fail;
snprintf(nspath, sizeof(nspath), "%s/%s", "/var/run/netns", name);
nsfd = open(nspath, O_RDONLY | O_CLOEXEC);
if (!ASSERT_GE(nsfd, 0, "open netns fd"))
goto fail;
err = setns_by_fd(nsfd);
if (!ASSERT_OK(err, "setns_by_fd"))
goto fail;
return token;
fail:
free(token);
return NULL;
}
void close_netns(struct nstoken *token)
{
ASSERT_OK(setns_by_fd(token->orig_netns_fd), "setns_by_fd");
free(token);
}

View file

@ -55,4 +55,13 @@ int make_sockaddr(int family, const char *addr_str, __u16 port,
struct sockaddr_storage *addr, socklen_t *len);
char *ping_command(int family);
struct nstoken;
/**
* open_netns() - Switch to specified network namespace by name.
*
* Returns token with which to restore the original namespace
* using close_netns().
*/
struct nstoken *open_netns(const char *name);
void close_netns(struct nstoken *token);
#endif

View file

@ -10,8 +10,6 @@
* to drop unexpected traffic.
*/
#define _GNU_SOURCE
#include <arpa/inet.h>
#include <linux/if.h>
#include <linux/if_tun.h>
@ -19,10 +17,8 @@
#include <linux/sysctl.h>
#include <linux/time_types.h>
#include <linux/net_tstamp.h>
#include <sched.h>
#include <stdbool.h>
#include <stdio.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <unistd.h>
@ -92,91 +88,6 @@ static int write_file(const char *path, const char *newval)
return 0;
}
struct nstoken {
int orig_netns_fd;
};
static int setns_by_fd(int nsfd)
{
int err;
err = setns(nsfd, CLONE_NEWNET);
close(nsfd);
if (!ASSERT_OK(err, "setns"))
return err;
/* Switch /sys to the new namespace so that e.g. /sys/class/net
* reflects the devices in the new namespace.
*/
err = unshare(CLONE_NEWNS);
if (!ASSERT_OK(err, "unshare"))
return err;
/* Make our /sys mount private, so the following umount won't
* trigger the global umount in case it's shared.
*/
err = mount("none", "/sys", NULL, MS_PRIVATE, NULL);
if (!ASSERT_OK(err, "remount private /sys"))
return err;
err = umount2("/sys", MNT_DETACH);
if (!ASSERT_OK(err, "umount2 /sys"))
return err;
err = mount("sysfs", "/sys", "sysfs", 0, NULL);
if (!ASSERT_OK(err, "mount /sys"))
return err;
err = mount("bpffs", "/sys/fs/bpf", "bpf", 0, NULL);
if (!ASSERT_OK(err, "mount /sys/fs/bpf"))
return err;
return 0;
}
/**
* open_netns() - Switch to specified network namespace by name.
*
* Returns token with which to restore the original namespace
* using close_netns().
*/
static struct nstoken *open_netns(const char *name)
{
int nsfd;
char nspath[PATH_MAX];
int err;
struct nstoken *token;
token = calloc(1, sizeof(struct nstoken));
if (!ASSERT_OK_PTR(token, "malloc token"))
return NULL;
token->orig_netns_fd = open("/proc/self/ns/net", O_RDONLY);
if (!ASSERT_GE(token->orig_netns_fd, 0, "open /proc/self/ns/net"))
goto fail;
snprintf(nspath, sizeof(nspath), "%s/%s", "/var/run/netns", name);
nsfd = open(nspath, O_RDONLY | O_CLOEXEC);
if (!ASSERT_GE(nsfd, 0, "open netns fd"))
goto fail;
err = setns_by_fd(nsfd);
if (!ASSERT_OK(err, "setns_by_fd"))
goto fail;
return token;
fail:
free(token);
return NULL;
}
static void close_netns(struct nstoken *token)
{
ASSERT_OK(setns_by_fd(token->orig_netns_fd), "setns_by_fd");
free(token);
}
static int netns_setup_namespaces(const char *verb)
{
const char * const *ns = namespaces;