1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2020 Carlos Neira cneirabustos@gmail.com */
3
4 #define _GNU_SOURCE
5 #include <test_progs.h>
6 #include "test_ns_current_pid_tgid.skel.h"
7 #include <sys/stat.h>
8 #include <sys/types.h>
9 #include <unistd.h>
10 #include <sys/syscall.h>
11 #include <sched.h>
12 #include <sys/wait.h>
13 #include <sys/mount.h>
14 #include <fcntl.h>
15 #include "network_helpers.h"
16
17 #define STACK_SIZE (1024 * 1024)
18 static char child_stack[STACK_SIZE];
19
get_pid_tgid(pid_t * pid,pid_t * tgid,struct test_ns_current_pid_tgid__bss * bss)20 static int get_pid_tgid(pid_t *pid, pid_t *tgid,
21 struct test_ns_current_pid_tgid__bss *bss)
22 {
23 struct stat st;
24 int err;
25
26 *pid = syscall(SYS_gettid);
27 *tgid = getpid();
28
29 err = stat("/proc/self/ns/pid", &st);
30 if (!ASSERT_OK(err, "stat /proc/self/ns/pid"))
31 return err;
32
33 bss->dev = st.st_dev;
34 bss->ino = st.st_ino;
35 bss->user_pid = 0;
36 bss->user_tgid = 0;
37 return 0;
38 }
39
test_current_pid_tgid_tp(void * args)40 static int test_current_pid_tgid_tp(void *args)
41 {
42 struct test_ns_current_pid_tgid__bss *bss;
43 struct test_ns_current_pid_tgid *skel;
44 int ret = -1, err;
45 pid_t tgid, pid;
46
47 skel = test_ns_current_pid_tgid__open();
48 if (!ASSERT_OK_PTR(skel, "test_ns_current_pid_tgid__open"))
49 return ret;
50
51 bpf_program__set_autoload(skel->progs.tp_handler, true);
52
53 err = test_ns_current_pid_tgid__load(skel);
54 if (!ASSERT_OK(err, "test_ns_current_pid_tgid__load"))
55 goto cleanup;
56
57 bss = skel->bss;
58 if (get_pid_tgid(&pid, &tgid, bss))
59 goto cleanup;
60
61 err = test_ns_current_pid_tgid__attach(skel);
62 if (!ASSERT_OK(err, "test_ns_current_pid_tgid__attach"))
63 goto cleanup;
64
65 /* trigger tracepoint */
66 usleep(1);
67 if (!ASSERT_EQ(bss->user_pid, pid, "pid"))
68 goto cleanup;
69 if (!ASSERT_EQ(bss->user_tgid, tgid, "tgid"))
70 goto cleanup;
71 ret = 0;
72
73 cleanup:
74 test_ns_current_pid_tgid__destroy(skel);
75 return ret;
76 }
77
test_current_pid_tgid_cgrp(void * args)78 static int test_current_pid_tgid_cgrp(void *args)
79 {
80 struct test_ns_current_pid_tgid__bss *bss;
81 struct test_ns_current_pid_tgid *skel;
82 int server_fd = -1, ret = -1, err;
83 int cgroup_fd = *(int *)args;
84 pid_t tgid, pid;
85
86 skel = test_ns_current_pid_tgid__open();
87 if (!ASSERT_OK_PTR(skel, "test_ns_current_pid_tgid__open"))
88 return ret;
89
90 bpf_program__set_autoload(skel->progs.cgroup_bind4, true);
91
92 err = test_ns_current_pid_tgid__load(skel);
93 if (!ASSERT_OK(err, "test_ns_current_pid_tgid__load"))
94 goto cleanup;
95
96 bss = skel->bss;
97 if (get_pid_tgid(&pid, &tgid, bss))
98 goto cleanup;
99
100 skel->links.cgroup_bind4 = bpf_program__attach_cgroup(
101 skel->progs.cgroup_bind4, cgroup_fd);
102 if (!ASSERT_OK_PTR(skel->links.cgroup_bind4, "bpf_program__attach_cgroup"))
103 goto cleanup;
104
105 server_fd = start_server(AF_INET, SOCK_STREAM, NULL, 0, 0);
106 if (!ASSERT_GE(server_fd, 0, "start_server"))
107 goto cleanup;
108
109 if (!ASSERT_EQ(bss->user_pid, pid, "pid"))
110 goto cleanup;
111 if (!ASSERT_EQ(bss->user_tgid, tgid, "tgid"))
112 goto cleanup;
113 ret = 0;
114
115 cleanup:
116 if (server_fd >= 0)
117 close(server_fd);
118 test_ns_current_pid_tgid__destroy(skel);
119 return ret;
120 }
121
test_ns_current_pid_tgid_new_ns(int (* fn)(void *),void * arg)122 static void test_ns_current_pid_tgid_new_ns(int (*fn)(void *), void *arg)
123 {
124 int wstatus;
125 pid_t cpid;
126
127 /* Create a process in a new namespace, this process
128 * will be the init process of this new namespace hence will be pid 1.
129 */
130 cpid = clone(fn, child_stack + STACK_SIZE,
131 CLONE_NEWPID | SIGCHLD, arg);
132
133 if (!ASSERT_NEQ(cpid, -1, "clone"))
134 return;
135
136 if (!ASSERT_NEQ(waitpid(cpid, &wstatus, 0), -1, "waitpid"))
137 return;
138
139 if (!ASSERT_OK(WEXITSTATUS(wstatus), "newns_pidtgid"))
140 return;
141 }
142
test_in_netns(int (* fn)(void *),void * arg)143 static void test_in_netns(int (*fn)(void *), void *arg)
144 {
145 struct nstoken *nstoken = NULL;
146
147 SYS(cleanup, "ip netns add ns_current_pid_tgid");
148 SYS(cleanup, "ip -net ns_current_pid_tgid link set dev lo up");
149
150 nstoken = open_netns("ns_current_pid_tgid");
151 if (!ASSERT_OK_PTR(nstoken, "open_netns"))
152 goto cleanup;
153
154 test_ns_current_pid_tgid_new_ns(fn, arg);
155
156 cleanup:
157 if (nstoken)
158 close_netns(nstoken);
159 SYS_NOFAIL("ip netns del ns_current_pid_tgid");
160 }
161
162 /* TODO: use a different tracepoint */
serial_test_ns_current_pid_tgid(void)163 void serial_test_ns_current_pid_tgid(void)
164 {
165 if (test__start_subtest("root_ns_tp"))
166 test_current_pid_tgid_tp(NULL);
167 if (test__start_subtest("new_ns_tp"))
168 test_ns_current_pid_tgid_new_ns(test_current_pid_tgid_tp, NULL);
169 if (test__start_subtest("new_ns_cgrp")) {
170 int cgroup_fd = -1;
171
172 cgroup_fd = test__join_cgroup("/sock_addr");
173 if (ASSERT_GE(cgroup_fd, 0, "join_cgroup")) {
174 test_in_netns(test_current_pid_tgid_cgrp, &cgroup_fd);
175 close(cgroup_fd);
176 }
177 }
178 }
179