ipv6_flowlabel_mgr.c

  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
 45static bool cfg_long_running;
 46static bool cfg_verbose;
 47
 48static 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
 64static 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
 74static 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
165static 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
183int 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}