Commit 1e115a58 authored by Kui-Feng Lee's avatar Kui-Feng Lee Committed by Martin KaFai Lau
Browse files

selftests/bpf: netns_new() and netns_free() helpers. 



netns_new()/netns_free() create/delete network namespaces. They support the
option '-m' of test_progs to start/stop traffic monitor for the network
namespace being created for matched tests.

Acked-by: default avatarStanislav Fomichev <sdf@fomichev.me>
Signed-off-by: default avatarKui-Feng Lee <thinker.li@gmail.com>
Link: https://lore.kernel.org/r/20240815053254.470944-4-thinker.li@gmail.com


Signed-off-by: default avatarMartin KaFai Lau <martin.lau@kernel.org>
parent f5281aac

tools/testing/selftests/bpf/network_helpers.c

+46 −0
Original line number Diff line number Diff line
@@ -446,6 +446,52 @@ char *ping_command(int family) 
	return "ping";

}



int remove_netns(const char *name)

{

	char *cmd;

	int r;



	r = asprintf(&cmd, "ip netns del %s >/dev/null 2>&1", name);

	if (r < 0) {

		log_err("Failed to malloc cmd");

		return -1;

	}



	r = system(cmd);

	free(cmd);

	return r;

}



int make_netns(const char *name)

{

	char *cmd;

	int r;



	r = asprintf(&cmd, "ip netns add %s", name);

	if (r < 0) {

		log_err("Failed to malloc cmd");

		return -1;

	}



	r = system(cmd);

	free(cmd);



	if (r)

		return r;



	r = asprintf(&cmd, "ip -n %s link set lo up", name);

	if (r < 0) {

		log_err("Failed to malloc cmd for setting up lo");

		remove_netns(name);

		return -1;

	}



	r = system(cmd);

	free(cmd);



	return r;

}



struct nstoken {

	int orig_netns_fd;

};

tools/testing/selftests/bpf/network_helpers.h

+2 −0
Original line number Diff line number Diff line
@@ -93,6 +93,8 @@ struct nstoken; 
struct nstoken *open_netns(const char *name);

void close_netns(struct nstoken *token);

int send_recv_data(int lfd, int fd, uint32_t total_bytes);

int make_netns(const char *name);

int remove_netns(const char *name);



static __u16 csum_fold(__u32 csum)

{

tools/testing/selftests/bpf/test_progs.c

+88 −0
Original line number Diff line number Diff line
@@ -18,6 +18,8 @@ 
#include <bpf/btf.h>

#include "json_writer.h"



#include "network_helpers.h"



#ifdef __GLIBC__

#include <execinfo.h> /* backtrace */

#endif
@@ -642,6 +644,92 @@ int compare_stack_ips(int smap_fd, int amap_fd, int stack_trace_len) 
	return err;

}



struct netns_obj {

	char *nsname;

	struct tmonitor_ctx *tmon;

	struct nstoken *nstoken;

};



/* Create a new network namespace with the given name.

 *

 * Create a new network namespace and set the network namespace of the

 * current process to the new network namespace if the argument "open" is

 * true. This function should be paired with netns_free() to release the

 * resource and delete the network namespace.

 *

 * It also implements the functionality of the option "-m" by starting

 * traffic monitor on the background to capture the packets in this network

 * namespace if the current test or subtest matching the pattern.

 *

 * nsname: the name of the network namespace to create.

 * open: open the network namespace if true.

 *

 * Return: the network namespace object on success, NULL on failure.

 */

struct netns_obj *netns_new(const char *nsname, bool open)

{

	struct netns_obj *netns_obj = malloc(sizeof(*netns_obj));

	const char *test_name, *subtest_name;

	int r;



	if (!netns_obj)

		return NULL;

	memset(netns_obj, 0, sizeof(*netns_obj));



	netns_obj->nsname = strdup(nsname);

	if (!netns_obj->nsname)

		goto fail;



	/* Create the network namespace */

	r = make_netns(nsname);

	if (r)

		goto fail;



	/* Start traffic monitor */

	if (env.test->should_tmon ||

	    (env.subtest_state && env.subtest_state->should_tmon)) {

		test_name = env.test->test_name;

		subtest_name = env.subtest_state ? env.subtest_state->name : NULL;

		netns_obj->tmon = traffic_monitor_start(nsname, test_name, subtest_name);

		if (!netns_obj->tmon) {

			fprintf(stderr, "Failed to start traffic monitor for %s\n", nsname);

			goto fail;

		}

	} else {

		netns_obj->tmon = NULL;

	}



	if (open) {

		netns_obj->nstoken = open_netns(nsname);

		if (!netns_obj->nstoken)

			goto fail;

	}



	return netns_obj;

fail:

	traffic_monitor_stop(netns_obj->tmon);

	remove_netns(nsname);

	free(netns_obj->nsname);

	free(netns_obj);

	return NULL;

}



/* Delete the network namespace.

 *

 * This function should be paired with netns_new() to delete the namespace

 * created by netns_new().

 */

void netns_free(struct netns_obj *netns_obj)

{

	if (!netns_obj)

		return;

	traffic_monitor_stop(netns_obj->tmon);

	close_netns(netns_obj->nstoken);

	remove_netns(netns_obj->nsname);

	free(netns_obj->nsname);

	free(netns_obj);

}



/* extern declarations for test funcs */

#define DEFINE_TEST(name)				\

	extern void test_##name(void) __weak;		\

tools/testing/selftests/bpf/test_progs.h

+4 −0
Original line number Diff line number Diff line
@@ -430,6 +430,10 @@ int write_sysctl(const char *sysctl, const char *value); 
int get_bpf_max_tramp_links_from(struct btf *btf);

int get_bpf_max_tramp_links(void);



struct netns_obj;

struct netns_obj *netns_new(const char *name, bool open);

void netns_free(struct netns_obj *netns);



#ifdef __x86_64__

#define SYS_NANOSLEEP_KPROBE_NAME "__x64_sys_nanosleep"

#elif defined(__s390x__)