From: Chenbo Feng <fe...@google.com>
Added a per socket traffic monitoring option to illustrate the usage
of new getsockopt SO_COOKIE. The program is based on the socket traffic
monitoring program using xt_eBPF and in the new option the data entry
can be directly accessed using socket cookie. The cookie retrieved
allow us to lookup an element in the eBPF for a specific socket.
Signed-off-by: Chenbo Feng <fe...@google.com>
---
samples/bpf/cookie_uid_helper_example.c | 146 +++++++++++++++++++++++----
samples/bpf/run_cookie_uid_helper_example.sh | 4 +-
2 files changed, 127 insertions(+), 23 deletions(-)
mode change 100644 => 100755 samples/bpf/run_cookie_uid_helper_example.sh
diff --git a/samples/bpf/cookie_uid_helper_example.c
b/samples/bpf/cookie_uid_helper_example.c
index f6e5e58..ad5afed 100644
--- a/samples/bpf/cookie_uid_helper_example.c
+++ b/samples/bpf/cookie_uid_helper_example.c
@@ -4,10 +4,11 @@
* program into the xt_bpf match.
*
* TEST:
- * ./run_cookie_uid_helper_example.sh
- * Then generate some traffic in variate ways. ping 0 -c 10 would work
- * but the cookie and uid in this case could both be 0. A sample output
- * with some traffic generated by web browser is shown below:
+ * ./run_cookie_uid_helper_example.sh -option
+ * option:
+ * -t: do traffic monitoring test, the program will continuously
+ * print out network traffic happens after program started A sample
+ * output is shown below:
*
* cookie: 877, uid: 0x3e8, Pakcet Count: 20, Bytes Count: 11058
* cookie: 132, uid: 0x0, Pakcet Count: 2, Bytes Count: 286
@@ -18,6 +19,10 @@
* cookie: 0, uid: 0x0, Pakcet Count: 6, Bytes Count: 712
* cookie: 880, uid: 0xfffe, Pakcet Count: 1, Bytes Count: 70
*
+ * -s: do getsockopt SO_COOKIE test, the program will set up a pair of
+ * UDP sockets and send packets between them. And read out the traffic data
+ * directly from the ebpf map based on the socket cookie.
+ *
* Clean up: if using shell script, the script file will delete the iptables
* rule and unmount the bpf program when exit. Else the iptables rule need
* to be deleted by hand, see run_cookie_uid_helper_example.sh for detail.
@@ -34,6 +39,8 @@
#include <limits.h>
#include <linux/bpf.h>
#include <linux/if_ether.h>
+#include <net/if.h>
+#include <signal.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
@@ -46,6 +53,8 @@
#include <bpf/bpf.h>
#include "libbpf.h"
+#define PORT 8888
+
struct stats {
uint32_t uid;
uint64_t packets;
@@ -54,6 +63,8 @@ struct stats {
static int map_fd, prog_fd;
+static bool test_finish;
+
static void maps_create(void)
{
map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(uint32_t),
@@ -164,7 +175,7 @@ static void prog_attach_iptables(char *file)
printf("file path too long: %s\n", file);
exit(1);
}
- sprintf(rules, "iptables -A INPUT -m bpf --object-pinned %s -j ACCEPT",
+ sprintf(rules, "iptables -A OUTPUT -m bpf --object-pinned %s -j ACCEPT",
file);
ret = system(rules);
if (ret < 0) {
@@ -177,7 +188,8 @@ static void print_table(void)
{
struct stats curEntry;
uint32_t curN = UINT32_MAX;
- uint32_t nextN, res;
+ uint32_t nextN;
+ int res;
while (bpf_map_get_next_key(map_fd, &curN, &nextN) > -1) {
curN = nextN;
@@ -193,25 +205,117 @@ static void print_table(void)
}
}
-int main(int argc, char *argv[])
+static void udp_client(void)
{
- if (argc > 2) {
- printf("Too many argument provided\n");
- return 1;
- } else if (argc < 2) {
- printf("Usage: %s bpfObjName\n", argv[0]);
- return 1;
+ struct sockaddr_in si_other = {0};
+ struct sockaddr_in si_me = {0};
+ struct stats dataEntry;
+ int s_rcv, s_send, i, recv_len;
+ char message = 'a';
+ char buf;
+ uint64_t cookie;
+ int res;
+ socklen_t cookie_len = sizeof(cookie);
+ socklen_t slen = sizeof(si_other);
+
+ s_rcv = socket(PF_INET, SOCK_DGRAM, 0);
+ if (s_rcv < 0)
+ error(1, errno, "rcv socket creat failed!\n");
+ si_other.sin_family = AF_INET;
+ si_other.sin_port = htons(PORT);
+ if (inet_aton("127.0.0.1", &si_other.sin_addr) == 0)
+ error(1, errno, "inet_aton\n");
+ if (bind(s_rcv, (struct sockaddr *)&si_other, sizeof(si_other)) == -1)
+ error(1, errno, "bind\n");
+ s_send = socket(PF_INET, SOCK_DGRAM, 0);
+ if (s_send < 0)
+ error(1, errno, "send socket creat failed!\n");
+ res = getsockopt(s_send, SOL_SOCKET, SO_COOKIE, &cookie, &cookie_len);
+ if (res < 0)
+ printf("get cookie failed: %s\n", strerror(errno));
+ res = bpf_map_lookup_elem(map_fd, &cookie, &dataEntry);
+ if (res != -1)
+ error(1, errno, "socket stat found while flow not active\n");
+ for (i = 0; i < 10; i++) {
+ res = sendto(s_send, &message, sizeof(message), 0,
+ (struct sockaddr *)&si_other, slen);
+ if (res == -1)
+ error(1, errno, "send\n");
+ if (res != sizeof(message))
+ error(1, 0, "%uB != %luB\n", res, sizeof(message));
+ recv_len = recvfrom(s_rcv, &buf, sizeof(buf), 0,
+ (struct sockaddr *)&si_me, &slen);
+ if (recv_len < 0)
+ error(1, errno, "revieve\n");
+ res = memcmp(&(si_other.sin_addr), &(si_me.sin_addr),
+ sizeof(si_me.sin_addr));
+ if (res != 0)
+ error(1, EFAULT, "sender addr error: %d\n", res);
+ printf("Message received: %c\n", buf);
+ res = bpf_map_lookup_elem(map_fd, &cookie, &dataEntry);
+ if (res < 0)
+ error(1, errno, "lookup sk stat failed, cookie: %lu\n",
+ cookie);
+ printf("cookie: %lu, uid: 0x%x, Packet Count: %lu,"
+ " Bytes Count: %lu\n\n", cookie, dataEntry.uid,
+ dataEntry.packets, dataEntry.bytes);
}
+ close(s_send);
+ close(s_rcv);
+}
- maps_create();
- prog_load();
- prog_attach_iptables(argv[1]);
+static int usage(void)
+{
+ printf("Usage: ./run_cookie_uid_helper_example.sh"
+ " bpfObjName -option\n"
+ " -t traffic monitor test\n"
+ " -s getsockopt cookie test\n");
+ return 1;
+}
- while (true) {
- print_table();
- printf("\n");
- sleep(1);
- };
+void finish(int ret)
+{
+ test_finish = true;
+}
+
+int main(int argc, char *argv[])
+{
+ int opt;
+ bool cfg_test_traffic = false;
+ bool cfg_test_cookie = false;
+
+ if (argc != 3)
+ return usage();
+ while ((opt = getopt(argc, argv, "ts")) != -1) {
+ switch (opt) {
+ case 't':
+ cfg_test_traffic = true;
+ break;
+ case 's':
+ cfg_test_cookie = true;
+ break;
+ default:
+ printf("unknown option %c\n", opt);
+ usage();
+ return -1;
+ }
+ }
+ maps_create();
+ prog_load();
+ prog_attach_iptables(argv[2]);
+ if (cfg_test_traffic) {
+ if (signal(SIGINT, finish) == SIG_ERR)
+ error(1, errno, "register handler failed");
+ while (!test_finish) {
+ print_table();
+ printf("\n");
+ sleep(1);
+ };
+ } else if (cfg_test_cookie) {
+ udp_client();
+ }
+ close(prog_fd);
+ close(map_fd);
return 0;
}
diff --git a/samples/bpf/run_cookie_uid_helper_example.sh
b/samples/bpf/run_cookie_uid_helper_example.sh
old mode 100644
new mode 100755
index 40da8aa..f898cfa
--- a/samples/bpf/run_cookie_uid_helper_example.sh
+++ b/samples/bpf/run_cookie_uid_helper_example.sh
@@ -4,11 +4,11 @@ root_dir=$local_dir/../..
mnt_dir=$(mktemp -d --tmp)
on_exit() {
- iptables -D INPUT -m bpf --object-pinned ${mnt_dir}/bpf_prog -j ACCEPT
+ iptables -D OUTPUT -m bpf --object-pinned ${mnt_dir}/bpf_prog -j ACCEPT
umount ${mnt_dir}
rm -r ${mnt_dir}
}
trap on_exit EXIT
mount -t bpf bpf ${mnt_dir}
-./per_socket_stats_example ${mnt_dir}/bpf_prog
+./per_socket_stats_example ${mnt_dir}/bpf_prog $1
--
2.7.4
