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-rw-r--r--samples/bpf/Makefile3
-rw-r--r--samples/bpf/cookie_uid_helper_example.c217
-rw-r--r--samples/bpf/libbpf.h10
-rw-r--r--samples/bpf/run_cookie_uid_helper_example.sh14
4 files changed, 244 insertions, 0 deletions
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 91c1d616d975..d42b495b0992 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -35,6 +35,7 @@ hostprogs-y += tc_l2_redirect
35hostprogs-y += lwt_len_hist 35hostprogs-y += lwt_len_hist
36hostprogs-y += xdp_tx_iptunnel 36hostprogs-y += xdp_tx_iptunnel
37hostprogs-y += test_map_in_map 37hostprogs-y += test_map_in_map
38hostprogs-y += per_socket_stats_example
38 39
39# Libbpf dependencies 40# Libbpf dependencies
40LIBBPF := ../../tools/lib/bpf/bpf.o 41LIBBPF := ../../tools/lib/bpf/bpf.o
@@ -74,6 +75,7 @@ tc_l2_redirect-objs := bpf_load.o $(LIBBPF) tc_l2_redirect_user.o
74lwt_len_hist-objs := bpf_load.o $(LIBBPF) lwt_len_hist_user.o 75lwt_len_hist-objs := bpf_load.o $(LIBBPF) lwt_len_hist_user.o
75xdp_tx_iptunnel-objs := bpf_load.o $(LIBBPF) xdp_tx_iptunnel_user.o 76xdp_tx_iptunnel-objs := bpf_load.o $(LIBBPF) xdp_tx_iptunnel_user.o
76test_map_in_map-objs := bpf_load.o $(LIBBPF) test_map_in_map_user.o 77test_map_in_map-objs := bpf_load.o $(LIBBPF) test_map_in_map_user.o
78per_socket_stats_example-objs := $(LIBBPF) cookie_uid_helper_example.o
77 79
78# Tell kbuild to always build the programs 80# Tell kbuild to always build the programs
79always := $(hostprogs-y) 81always := $(hostprogs-y)
@@ -108,6 +110,7 @@ always += sampleip_kern.o
108always += lwt_len_hist_kern.o 110always += lwt_len_hist_kern.o
109always += xdp_tx_iptunnel_kern.o 111always += xdp_tx_iptunnel_kern.o
110always += test_map_in_map_kern.o 112always += test_map_in_map_kern.o
113always += cookie_uid_helper_example.o
111 114
112HOSTCFLAGS += -I$(objtree)/usr/include 115HOSTCFLAGS += -I$(objtree)/usr/include
113HOSTCFLAGS += -I$(srctree)/tools/lib/ 116HOSTCFLAGS += -I$(srctree)/tools/lib/
diff --git a/samples/bpf/cookie_uid_helper_example.c b/samples/bpf/cookie_uid_helper_example.c
new file mode 100644
index 000000000000..f6e5e58931c5
--- /dev/null
+++ b/samples/bpf/cookie_uid_helper_example.c
@@ -0,0 +1,217 @@
1/* This test is a demo of using get_socket_uid and get_socket_cookie
2 * helper function to do per socket based network traffic monitoring.
3 * It requires iptables version higher then 1.6.1. to load pinned eBPF
4 * program into the xt_bpf match.
5 *
6 * TEST:
7 * ./run_cookie_uid_helper_example.sh
8 * Then generate some traffic in variate ways. ping 0 -c 10 would work
9 * but the cookie and uid in this case could both be 0. A sample output
10 * with some traffic generated by web browser is shown below:
11 *
12 * cookie: 877, uid: 0x3e8, Pakcet Count: 20, Bytes Count: 11058
13 * cookie: 132, uid: 0x0, Pakcet Count: 2, Bytes Count: 286
14 * cookie: 812, uid: 0x3e8, Pakcet Count: 3, Bytes Count: 1726
15 * cookie: 802, uid: 0x3e8, Pakcet Count: 2, Bytes Count: 104
16 * cookie: 877, uid: 0x3e8, Pakcet Count: 20, Bytes Count: 11058
17 * cookie: 831, uid: 0x3e8, Pakcet Count: 2, Bytes Count: 104
18 * cookie: 0, uid: 0x0, Pakcet Count: 6, Bytes Count: 712
19 * cookie: 880, uid: 0xfffe, Pakcet Count: 1, Bytes Count: 70
20 *
21 * Clean up: if using shell script, the script file will delete the iptables
22 * rule and unmount the bpf program when exit. Else the iptables rule need
23 * to be deleted by hand, see run_cookie_uid_helper_example.sh for detail.
24 */
25
26#define _GNU_SOURCE
27
28#define offsetof(type, member) __builtin_offsetof(type, member)
29#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
30
31#include <arpa/inet.h>
32#include <errno.h>
33#include <error.h>
34#include <limits.h>
35#include <linux/bpf.h>
36#include <linux/if_ether.h>
37#include <stdbool.h>
38#include <stdint.h>
39#include <stdio.h>
40#include <stdlib.h>
41#include <string.h>
42#include <sys/socket.h>
43#include <sys/stat.h>
44#include <sys/types.h>
45#include <unistd.h>
46#include <bpf/bpf.h>
47#include "libbpf.h"
48
49struct stats {
50 uint32_t uid;
51 uint64_t packets;
52 uint64_t bytes;
53};
54
55static int map_fd, prog_fd;
56
57static void maps_create(void)
58{
59 map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(uint32_t),
60 sizeof(struct stats), 100, 0);
61 if (map_fd < 0)
62 error(1, errno, "map create failed!\n");
63}
64
65static void prog_load(void)
66{
67 static char log_buf[1 << 16];
68
69 struct bpf_insn prog[] = {
70 /*
71 * Save sk_buff for future usage. value stored in R6 to R10 will
72 * not be reset after a bpf helper function call.
73 */
74 BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
75 /*
76 * pc1: BPF_FUNC_get_socket_cookie takes one parameter,
77 * R1: sk_buff
78 */
79 BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
80 BPF_FUNC_get_socket_cookie),
81 /* pc2-4: save &socketCookie to r7 for future usage*/
82 BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
83 BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
84 BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
85 /*
86 * pc5-8: set up the registers for BPF_FUNC_map_lookup_elem,
87 * it takes two parameters (R1: map_fd, R2: &socket_cookie)
88 */
89 BPF_LD_MAP_FD(BPF_REG_1, map_fd),
90 BPF_MOV64_REG(BPF_REG_2, BPF_REG_7),
91 BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
92 BPF_FUNC_map_lookup_elem),
93 /*
94 * pc9. if r0 != 0x0, go to pc+14, since we have the cookie
95 * stored already
96 * Otherwise do pc10-22 to setup a new data entry.
97 */
98 BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 14),
99 BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
100 BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
101 BPF_FUNC_get_socket_uid),
102 /*
103 * Place a struct stats in the R10 stack and sequentially
104 * place the member value into the memory. Packets value
105 * is set by directly place a IMM value 1 into the stack.
106 */
107 BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0,
108 -32 + offsetof(struct stats, uid)),
109 BPF_ST_MEM(BPF_DW, BPF_REG_10,
110 -32 + offsetof(struct stats, packets), 1),
111 /*
112 * __sk_buff is a special struct used for eBPF program to
113 * directly access some sk_buff field.
114 */
115 BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_6,
116 offsetof(struct __sk_buff, len)),
117 BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_1,
118 -32 + offsetof(struct stats, bytes)),
119 /*
120 * add new map entry using BPF_FUNC_map_update_elem, it takes
121 * 4 parameters (R1: map_fd, R2: &socket_cookie, R3: &stats,
122 * R4: flags)
123 */
124 BPF_LD_MAP_FD(BPF_REG_1, map_fd),
125 BPF_MOV64_REG(BPF_REG_2, BPF_REG_7),
126 BPF_MOV64_REG(BPF_REG_3, BPF_REG_10),
127 BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, -32),
128 BPF_MOV64_IMM(BPF_REG_4, 0),
129 BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
130 BPF_FUNC_map_update_elem),
131 BPF_JMP_IMM(BPF_JA, 0, 0, 5),
132 /*
133 * pc24-30 update the packet info to a exist data entry, it can
134 * be done by directly write to pointers instead of using
135 * BPF_FUNC_map_update_elem helper function
136 */
137 BPF_MOV64_REG(BPF_REG_9, BPF_REG_0),
138 BPF_MOV64_IMM(BPF_REG_1, 1),
139 BPF_STX_XADD(BPF_DW, BPF_REG_9, BPF_REG_1,
140 offsetof(struct stats, packets)),
141 BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_6,
142 offsetof(struct __sk_buff, len)),
143 BPF_STX_XADD(BPF_DW, BPF_REG_9, BPF_REG_1,
144 offsetof(struct stats, bytes)),
145 BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_6,
146 offsetof(struct __sk_buff, len)),
147 BPF_EXIT_INSN(),
148 };
149 prog_fd = bpf_load_program(BPF_PROG_TYPE_SOCKET_FILTER, prog,
150 ARRAY_SIZE(prog), "GPL", 0,
151 log_buf, sizeof(log_buf));
152 if (prog_fd < 0)
153 error(1, errno, "failed to load prog\n%s\n", log_buf);
154}
155
156static void prog_attach_iptables(char *file)
157{
158 int ret;
159 char rules[100];
160
161 if (bpf_obj_pin(prog_fd, file))
162 error(1, errno, "bpf_obj_pin");
163 if (strlen(file) > 50) {
164 printf("file path too long: %s\n", file);
165 exit(1);
166 }
167 sprintf(rules, "iptables -A INPUT -m bpf --object-pinned %s -j ACCEPT",
168 file);
169 ret = system(rules);
170 if (ret < 0) {
171 printf("iptables rule update failed: %d/n", WEXITSTATUS(ret));
172 exit(1);
173 }
174}
175
176static void print_table(void)
177{
178 struct stats curEntry;
179 uint32_t curN = UINT32_MAX;
180 uint32_t nextN, res;
181
182 while (bpf_map_get_next_key(map_fd, &curN, &nextN) > -1) {
183 curN = nextN;
184 res = bpf_map_lookup_elem(map_fd, &curN, &curEntry);
185 if (res < 0) {
186 error(1, errno, "fail to get entry value of Key: %u\n",
187 curN);
188 } else {
189 printf("cookie: %u, uid: 0x%x, Packet Count: %lu,"
190 " Bytes Count: %lu\n", curN, curEntry.uid,
191 curEntry.packets, curEntry.bytes);
192 }
193 }
194}
195
196int main(int argc, char *argv[])
197{
198 if (argc > 2) {
199 printf("Too many argument provided\n");
200 return 1;
201 } else if (argc < 2) {
202 printf("Usage: %s bpfObjName\n", argv[0]);
203 return 1;
204 }
205
206 maps_create();
207 prog_load();
208 prog_attach_iptables(argv[1]);
209
210 while (true) {
211 print_table();
212 printf("\n");
213 sleep(1);
214 };
215
216 return 0;
217}
diff --git a/samples/bpf/libbpf.h b/samples/bpf/libbpf.h
index 3705fba453a0..8ab36a04c174 100644
--- a/samples/bpf/libbpf.h
+++ b/samples/bpf/libbpf.h
@@ -135,6 +135,16 @@ struct bpf_insn;
135 .off = OFF, \ 135 .off = OFF, \
136 .imm = 0 }) 136 .imm = 0 })
137 137
138/* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */
139
140#define BPF_STX_XADD(SIZE, DST, SRC, OFF) \
141 ((struct bpf_insn) { \
142 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD, \
143 .dst_reg = DST, \
144 .src_reg = SRC, \
145 .off = OFF, \
146 .imm = 0 })
147
138/* Memory store, *(uint *) (dst_reg + off16) = imm32 */ 148/* Memory store, *(uint *) (dst_reg + off16) = imm32 */
139 149
140#define BPF_ST_MEM(SIZE, DST, OFF, IMM) \ 150#define BPF_ST_MEM(SIZE, DST, OFF, IMM) \
diff --git a/samples/bpf/run_cookie_uid_helper_example.sh b/samples/bpf/run_cookie_uid_helper_example.sh
new file mode 100644
index 000000000000..40da8aa75c44
--- /dev/null
+++ b/samples/bpf/run_cookie_uid_helper_example.sh
@@ -0,0 +1,14 @@
1#!/bin/bash
2local_dir="$(pwd)"
3root_dir=$local_dir/../..
4mnt_dir=$(mktemp -d --tmp)
5
6on_exit() {
7 iptables -D INPUT -m bpf --object-pinned ${mnt_dir}/bpf_prog -j ACCEPT
8 umount ${mnt_dir}
9 rm -r ${mnt_dir}
10}
11
12trap on_exit EXIT
13mount -t bpf bpf ${mnt_dir}
14./per_socket_stats_example ${mnt_dir}/bpf_prog
generated by cgit v1.2.2 (git 2.25.0) at 2026-05-27 11:51:34 -0400