On 07/11, Alexis Lothoré (eBPF Foundation) wrote:
> test_xdp_veth.sh tests that XDP return codes work as expected, by bringing
> up multiple veth pairs isolated in different namespaces, attaching specific
> xdp programs to each interface, and ensuring that the whole chain allows to
> ping one end interface from the first one. The test runs well but is
> currently not integrated in test_progs, which prevents it from being run
> automatically in the CI infrastructure.
>
> Rewrite it as a C test relying on libbpf to allow running it in the CI
> infrastructure. The new code brings up the same network infrastructure and
> reuses the same eBPF programs as test_xdp_veth.sh, for which skeletons are
> already generated by the bpf tests makefile.
>
> Signed-off-by: Alexis Lothoré <alexis.lothore@xxxxxxxxxxx>
> ---
> The new code has been tested in an aarch64 qemu instance:
> Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
>
> I have also checked that some minor alterations in the network
> configuration (altering the redirect map, or not loading one of the xdp
> programs) make the test fail.
>
> On my testing setup, the test takes a bit more than 3 seconds to run on
> average.
> ---
> .../selftests/bpf/prog_tests/test_xdp_veth.c | 234 +++++++++++++++++++++
> 1 file changed, 234 insertions(+)
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/test_xdp_veth.c b/tools/testing/selftests/bpf/prog_tests/test_xdp_veth.c
> new file mode 100644
> index 000000000000..40d85aece984
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/prog_tests/test_xdp_veth.c
> @@ -0,0 +1,234 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/**
> + * Create 3 namespaces with 3 veth peers, and
> + * forward packets in-between using native XDP
> + *
> + * XDP_TX
> + * NS1(veth11) NS2(veth22) NS3(veth33)
> + * | | |
> + * | | |
> + * (veth1, (veth2, (veth3,
> + * id:111) id:122) id:133)
> + * ^ | ^ | ^ |
> + * | | XDP_REDIRECT | | XDP_REDIRECT | |
> + * | ------------------ ------------------ |
> + * -----------------------------------------
> + * XDP_REDIRECT
> + */
> +
> +#define _GNU_SOURCE
> +#include <net/if.h>
> +#include "test_progs.h"
> +#include "network_helpers.h"
> +#include "xdp_dummy.skel.h"
> +#include "xdp_redirect_map.skel.h"
> +#include "xdp_tx.skel.h"
> +
> +#define VETH_PAIRS_COUNT 3
> +#define NS_NAME_MAX_LEN 16
> +#define NS_SUFFIX_LEN 6
> +#define VETH_NAME_MAX_LEN 16
> +#define IP_SRC "10.1.1.11"
> +#define IP_DST "10.1.1.33"
> +#define IP_CMD_MAX_LEN 128
> +
> +struct skeletons {
> + struct xdp_dummy *xdp_dummy;
> + struct xdp_tx *xdp_tx;
> + struct xdp_redirect_map *xdp_redirect_maps;
> +};
> +
> +struct veth_configuration {
> + char local_veth[VETH_NAME_MAX_LEN]; /* Interface in main namespace */
> + char remote_veth[VETH_NAME_MAX_LEN]; /* Peer interface in dedicated namespace*/
> + char namespace[NS_NAME_MAX_LEN]; /* Namespace for the remote veth */
> + char next_veth[VETH_NAME_MAX_LEN]; /* Local interface to redirect traffic to */
> + char *remote_addr; /* IP address of the remote veth */
> +};
> +
> +static struct veth_configuration config[VETH_PAIRS_COUNT] = {
> + {
> + .local_veth = "veth1",
> + .remote_veth = "veth11",
> + .next_veth = "veth2",
> + .remote_addr = IP_SRC
> + },
> + {
> + .local_veth = "veth2",
> + .remote_veth = "veth22",
> + .next_veth = "veth3",
> + .remote_addr = NULL
> + },
> + {
> + .local_veth = "veth3",
> + .remote_veth = "veth33",
> + .next_veth = "veth1",
> + .remote_addr = IP_DST
> + }
> +};
[..]
> +static void generate_random_ns_name(int index, char *out)
> +{
> + int random, count, i;
> +
> + count = snprintf(out, NS_NAME_MAX_LEN, "ns%d-", index);
> + for(i=0; i<NS_SUFFIX_LEN; i++) {
> + random=rand() % 2;
> + out[count++]= random ? 'a' + rand() % 26 : 'A' + rand() % 26;
> + }
> + out[count] = 0;
> +}
It's been customary to hard-code netns names for all the tests we have, so
maybe it's ok here as well?
> +static int attach_programs_to_veth_pair(struct skeletons *skeletons, int index)
> +{
> + struct bpf_program *local_prog, *remote_prog;
> + struct bpf_link **local_link, **remote_link;
> + struct nstoken *nstoken;
> + struct bpf_link *link;
> + int interface;
> +
[..]
> + switch(index) {
Can you pls run the patch through the checkpatch.pl? The formatting
looks wrong, should be 'switch (index)'. Applies to 'if()' elsewhere as
well.
> + case 0:
> + local_prog = skeletons->xdp_redirect_maps->progs.xdp_redirect_map_0;
> + local_link = &skeletons->xdp_redirect_maps->links.xdp_redirect_map_0;
> + remote_prog = skeletons->xdp_dummy->progs.xdp_dummy_prog;
> + remote_link = &skeletons->xdp_dummy->links.xdp_dummy_prog;
> + break;
> + case 1:
> + local_prog = skeletons->xdp_redirect_maps->progs.xdp_redirect_map_1;
> + local_link = &skeletons->xdp_redirect_maps->links.xdp_redirect_map_1;
> + remote_prog = skeletons->xdp_tx->progs.xdp_tx;
> + remote_link = &skeletons->xdp_tx->links.xdp_tx;
> + break;
> + case 2:
> + local_prog = skeletons->xdp_redirect_maps->progs.xdp_redirect_map_2;
> + local_link = &skeletons->xdp_redirect_maps->links.xdp_redirect_map_2;
> + remote_prog = skeletons->xdp_dummy->progs.xdp_dummy_prog;
> + remote_link = &skeletons->xdp_dummy->links.xdp_dummy_prog;
> + break;
> + }
> + interface = if_nametoindex(config[index].local_veth);
> + if(!ASSERT_NEQ(interface, 0, "non zero interface index"))
> + return -1;
> + link = bpf_program__attach_xdp(local_prog, interface);
> + if (!ASSERT_OK_PTR(link, "attach xdp program to local veth"))
> + return -1;
> + *local_link = link;
> + nstoken = open_netns(config[index].namespace);
> + if (!ASSERT_OK_PTR(nstoken, "switch to remote veth namespace"))
> + return -1;
> + interface = if_nametoindex(config[index].remote_veth);
> + if(!ASSERT_NEQ(interface, 0, "non zero interface index"))
> + return -1;
> + link = bpf_program__attach_xdp(remote_prog, interface);
> + *remote_link = link;
> + close_netns(nstoken);
> + if (!ASSERT_OK_PTR(link, "attach xdp program to remote veth"))
> + return -1;
> +
> + return 0;
> +}
> +
> +static int configure_network(struct skeletons *skeletons) {
> + int interface_id;
> + int map_fd;
> + int err;
> + int i=0;
> +
> + /* First create and configure all interfaces */
> + for(i=0; i<VETH_PAIRS_COUNT; i++) {
> + generate_random_ns_name(i+1, config[i].namespace);
> +
> + SYS(fail, "ip netns add %s", config[i].namespace);
> + SYS(fail, "ip link add %s type veth peer name %s netns %s",
> + config[i].local_veth,
> + config[i].remote_veth,
> + config[i].namespace);
> + SYS(fail, "ip link set dev %s up", config[i].local_veth);
> + if (config[i].remote_addr)
> + SYS(fail, "ip -n %s addr add %s/24 dev %s",
> + config[i].namespace, config[i].remote_addr, config[i].remote_veth);
> + SYS(fail, "ip -n %s link set dev %s up",
> + config[i].namespace, config[i].remote_veth);
> + }
> +
> + /* Then configure the redirect map and attach programs to interfaces */
> + map_fd = bpf_map__fd(skeletons->xdp_redirect_maps->maps.tx_port);
> + if (!ASSERT_GE(map_fd, 0, "open redirect map"))
> + goto fail;
> + for (i=0; i<VETH_PAIRS_COUNT; i++) {
> + interface_id = if_nametoindex(config[i].next_veth);
> + if(!ASSERT_NEQ(interface_id, 0, "non zero interface index"))
> + goto fail;
> + err = bpf_map_update_elem(map_fd, &i, &interface_id, BPF_ANY);
> + if (!ASSERT_OK(err, "configure interface redirection through map"))
> + goto fail;
> + if(attach_programs_to_veth_pair(skeletons, i))
> + goto fail;
> + }
> +
> + return 0;
> +
> +fail:
> + return -1;
> +}
> +
> +static void cleanup_network()
> +{
> + char cmd[IP_CMD_MAX_LEN];
> + int i;
> +
> + /* Deleting namespaces is enough to automatically remove veth pairs as well
> + */
> + for(i=0; i<VETH_PAIRS_COUNT; i++) {
> + if(config[i].namespace[0] == 0)
> + continue;
[..]
> + snprintf(cmd, IP_CMD_MAX_LEN, "ip netns del %s", config[i].namespace);
> + system(cmd);
SYS_NOFAIL to avoid separate snprintf?
> + }
> +}
> +
> +static int check_ping(struct skeletons *skeletons)
> +{
> + char cmd[IP_CMD_MAX_LEN];
> +
> + /* Test: if all interfaces are properly configured, we must be able to ping
> + * veth33 from veth11
> + */
> + snprintf(cmd, IP_CMD_MAX_LEN,
> + "ip netns exec %s ping -c 1 -W 1 %s > /dev/null",
> + config[0].namespace, IP_DST);
> + return system(cmd);
SYS_NOFAL here as well?
Btw, not sure it makes sense to split that work into 3 patches. After
you first patch the test is broken anyway, so might as well just delete
the script at that point...
