1 // SPDX-License-Identifier: GPL-2.0
2 /* Test IPV6_FLOWINFO_MGR */
3 
4 #define _GNU_SOURCE
5 
6 #include <arpa/inet.h>
7 #include <error.h>
8 #include <errno.h>
9 #include <limits.h>
10 #include <linux/in6.h>
11 #include <stdbool.h>
12 #include <stdio.h>
13 #include <stdint.h>
14 #include <stdlib.h>
15 #include <string.h>
16 #include <sys/socket.h>
17 #include <sys/stat.h>
18 #include <sys/time.h>
19 #include <sys/types.h>
20 #include <sys/wait.h>
21 #include <unistd.h>
22 
23 /* uapi/glibc weirdness may leave this undefined */
24 #ifndef IPV6_FLOWLABEL_MGR
25 #define IPV6_FLOWLABEL_MGR	32
26 #endif
27 
28 /* from net/ipv6/ip6_flowlabel.c */
29 #define FL_MIN_LINGER		6
30 
31 #define explain(x)							\
32 	do { if (cfg_verbose) fprintf(stderr, "       " x "\n"); } while (0)
33 
34 #define __expect(x)							\
35 	do {								\
36 		if (!(x))						\
37 			fprintf(stderr, "[OK]   " #x "\n");		\
38 		else							\
39 			error(1, 0, "[ERR]  " #x " (line %d)", __LINE__); \
40 	} while (0)
41 
42 #define expect_pass(x)	__expect(x)
43 #define expect_fail(x)	__expect(!(x))
44 
45 static bool cfg_long_running;
46 static bool cfg_verbose;
47 
48 static int flowlabel_get(int fd, uint32_t label, uint8_t share, uint16_t flags)
49 {
50 	struct in6_flowlabel_req req = {
51 		.flr_action = IPV6_FL_A_GET,
52 		.flr_label = htonl(label),
53 		.flr_flags = flags,
54 		.flr_share = share,
55 	};
56 
57 	/* do not pass IPV6_ADDR_ANY or IPV6_ADDR_MAPPED */
58 	req.flr_dst.s6_addr[0] = 0xfd;
59 	req.flr_dst.s6_addr[15] = 0x1;
60 
61 	return setsockopt(fd, SOL_IPV6, IPV6_FLOWLABEL_MGR, &req, sizeof(req));
62 }
63 
64 static int flowlabel_put(int fd, uint32_t label)
65 {
66 	struct in6_flowlabel_req req = {
67 		.flr_action = IPV6_FL_A_PUT,
68 		.flr_label = htonl(label),
69 	};
70 
71 	return setsockopt(fd, SOL_IPV6, IPV6_FLOWLABEL_MGR, &req, sizeof(req));
72 }
73 
74 static void run_tests(int fd)
75 {
76 	int wstatus;
77 	pid_t pid;
78 
79 	explain("cannot get non-existent label");
80 	expect_fail(flowlabel_get(fd, 1, IPV6_FL_S_ANY, 0));
81 
82 	explain("cannot put non-existent label");
83 	expect_fail(flowlabel_put(fd, 1));
84 
85 	explain("cannot create label greater than 20 bits");
86 	expect_fail(flowlabel_get(fd, 0x1FFFFF, IPV6_FL_S_ANY,
87 				  IPV6_FL_F_CREATE));
88 
89 	explain("create a new label (FL_F_CREATE)");
90 	expect_pass(flowlabel_get(fd, 1, IPV6_FL_S_ANY, IPV6_FL_F_CREATE));
91 	explain("can get the label (without FL_F_CREATE)");
92 	expect_pass(flowlabel_get(fd, 1, IPV6_FL_S_ANY, 0));
93 	explain("can get it again with create flag set, too");
94 	expect_pass(flowlabel_get(fd, 1, IPV6_FL_S_ANY, IPV6_FL_F_CREATE));
95 	explain("cannot get it again with the exclusive (FL_FL_EXCL) flag");
96 	expect_fail(flowlabel_get(fd, 1, IPV6_FL_S_ANY,
97 					 IPV6_FL_F_CREATE | IPV6_FL_F_EXCL));
98 	explain("can now put exactly three references");
99 	expect_pass(flowlabel_put(fd, 1));
100 	expect_pass(flowlabel_put(fd, 1));
101 	expect_pass(flowlabel_put(fd, 1));
102 	expect_fail(flowlabel_put(fd, 1));
103 
104 	explain("create a new exclusive label (FL_S_EXCL)");
105 	expect_pass(flowlabel_get(fd, 2, IPV6_FL_S_EXCL, IPV6_FL_F_CREATE));
106 	explain("cannot get it again in non-exclusive mode");
107 	expect_fail(flowlabel_get(fd, 2, IPV6_FL_S_ANY,  IPV6_FL_F_CREATE));
108 	explain("cannot get it again in exclusive mode either");
109 	expect_fail(flowlabel_get(fd, 2, IPV6_FL_S_EXCL, IPV6_FL_F_CREATE));
110 	expect_pass(flowlabel_put(fd, 2));
111 
112 	if (cfg_long_running) {
113 		explain("cannot reuse the label, due to linger");
114 		expect_fail(flowlabel_get(fd, 2, IPV6_FL_S_ANY,
115 					  IPV6_FL_F_CREATE));
116 		explain("after sleep, can reuse");
117 		sleep(FL_MIN_LINGER * 2 + 1);
118 		expect_pass(flowlabel_get(fd, 2, IPV6_FL_S_ANY,
119 					  IPV6_FL_F_CREATE));
120 	}
121 
122 	explain("create a new user-private label (FL_S_USER)");
123 	expect_pass(flowlabel_get(fd, 3, IPV6_FL_S_USER, IPV6_FL_F_CREATE));
124 	explain("cannot get it again in non-exclusive mode");
125 	expect_fail(flowlabel_get(fd, 3, IPV6_FL_S_ANY, 0));
126 	explain("cannot get it again in exclusive mode");
127 	expect_fail(flowlabel_get(fd, 3, IPV6_FL_S_EXCL, 0));
128 	explain("can get it again in user mode");
129 	expect_pass(flowlabel_get(fd, 3, IPV6_FL_S_USER, 0));
130 	explain("child process can get it too, but not after setuid(nobody)");
131 	pid = fork();
132 	if (pid == -1)
133 		error(1, errno, "fork");
134 	if (!pid) {
135 		expect_pass(flowlabel_get(fd, 3, IPV6_FL_S_USER, 0));
136 		if (setuid(USHRT_MAX))
137 			fprintf(stderr, "[INFO] skip setuid child test\n");
138 		else
139 			expect_fail(flowlabel_get(fd, 3, IPV6_FL_S_USER, 0));
140 		exit(0);
141 	}
142 	if (wait(&wstatus) == -1)
143 		error(1, errno, "wait");
144 	if (!WIFEXITED(wstatus) || WEXITSTATUS(wstatus) != 0)
145 		error(1, errno, "wait: unexpected child result");
146 
147 	explain("create a new process-private label (FL_S_PROCESS)");
148 	expect_pass(flowlabel_get(fd, 4, IPV6_FL_S_PROCESS, IPV6_FL_F_CREATE));
149 	explain("can get it again");
150 	expect_pass(flowlabel_get(fd, 4, IPV6_FL_S_PROCESS, 0));
151 	explain("child process cannot can get it");
152 	pid = fork();
153 	if (pid == -1)
154 		error(1, errno, "fork");
155 	if (!pid) {
156 		expect_fail(flowlabel_get(fd, 4, IPV6_FL_S_PROCESS, 0));
157 		exit(0);
158 	}
159 	if (wait(&wstatus) == -1)
160 		error(1, errno, "wait");
161 	if (!WIFEXITED(wstatus) || WEXITSTATUS(wstatus) != 0)
162 		error(1, errno, "wait: unexpected child result");
163 }
164 
165 static void parse_opts(int argc, char **argv)
166 {
167 	int c;
168 
169 	while ((c = getopt(argc, argv, "lv")) != -1) {
170 		switch (c) {
171 		case 'l':
172 			cfg_long_running = true;
173 			break;
174 		case 'v':
175 			cfg_verbose = true;
176 			break;
177 		default:
178 			error(1, 0, "%s: parse error", argv[0]);
179 		}
180 	}
181 }
182 
183 int main(int argc, char **argv)
184 {
185 	int fd;
186 
187 	parse_opts(argc, argv);
188 
189 	fd = socket(PF_INET6, SOCK_DGRAM, 0);
190 	if (fd == -1)
191 		error(1, errno, "socket");
192 
193 	run_tests(fd);
194 
195 	if (close(fd))
196 		error(1, errno, "close");
197 
198 	return 0;
199 }
200