| 1 | /* |
| 2 | * QEMU seccomp test suite |
| 3 | * |
| 4 | * Copyright (c) 2021 Red Hat, Inc. |
| 5 | * |
| 6 | * This library is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU Lesser General Public |
| 8 | * License as published by the Free Software Foundation; either |
| 9 | * version 2.1 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * This library is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public |
| 17 | * License along with this library; if not, see <http://www.gnu.org/licenses/>. |
| 18 | * |
| 19 | */ |
| 20 | |
| 21 | #include "qemu/osdep.h" |
| 22 | #include "qemu/config-file.h" |
| 23 | #include "qemu/option.h" |
| 24 | #include "system/seccomp.h" |
| 25 | #include "qapi/error.h" |
| 26 | #include "qemu/module.h" |
| 27 | |
| 28 | #include <sys/syscall.h> |
| 29 | |
| 30 | static void test_seccomp_helper(const char *args, bool killed, |
| 31 | int errnum, int (*doit)(void)) |
| 32 | { |
| 33 | if (g_test_subprocess()) { |
| 34 | QemuOptsList *olist; |
| 35 | QemuOpts *opts; |
| 36 | int ret; |
| 37 | |
| 38 | module_call_init(MODULE_INIT_OPTS); |
| 39 | olist = qemu_find_opts("sandbox"); |
| 40 | g_assert(olist != NULL); |
| 41 | |
| 42 | opts = qemu_opts_parse_noisily(olist, args, true); |
| 43 | g_assert(opts != NULL); |
| 44 | |
| 45 | parse_sandbox(NULL, opts, &error_abort); |
| 46 | |
| 47 | /* Running in a child process */ |
| 48 | ret = doit(); |
| 49 | |
| 50 | if (errnum != 0) { |
| 51 | g_assert(ret != 0); |
| 52 | g_assert(errno == errnum); |
| 53 | } else { |
| 54 | g_assert(ret == 0); |
| 55 | } |
| 56 | |
| 57 | _exit(0); |
| 58 | } else { |
| 59 | /* Running in main test process, spawning the child */ |
| 60 | g_test_trap_subprocess(NULL, 0, 0); |
| 61 | if (killed) { |
| 62 | g_test_trap_assert_failed(); |
| 63 | } else { |
| 64 | g_test_trap_assert_passed(); |
| 65 | } |
| 66 | } |
| 67 | } |
| 68 | |
| 69 | |
| 70 | static void test_seccomp_killed(const char *args, int (*doit)(void)) |
| 71 | { |
| 72 | test_seccomp_helper(args, true, 0, doit); |
| 73 | } |
| 74 | |
| 75 | static void test_seccomp_errno(const char *args, int errnum, int (*doit)(void)) |
| 76 | { |
| 77 | test_seccomp_helper(args, false, errnum, doit); |
| 78 | } |
| 79 | |
| 80 | static void test_seccomp_passed(const char *args, int (*doit)(void)) |
| 81 | { |
| 82 | test_seccomp_helper(args, false, 0, doit); |
| 83 | } |
| 84 | |
| 85 | #ifdef SYS_fork |
| 86 | static int doit_sys_fork(void) |
| 87 | { |
| 88 | int ret = syscall(SYS_fork); |
| 89 | if (ret < 0) { |
| 90 | return ret; |
| 91 | } |
| 92 | if (ret == 0) { |
| 93 | _exit(0); |
| 94 | } |
| 95 | return 0; |
| 96 | } |
| 97 | |
| 98 | static void test_seccomp_sys_fork_on_nospawn(void) |
| 99 | { |
| 100 | test_seccomp_killed("on,spawn=deny", doit_sys_fork); |
| 101 | } |
| 102 | |
| 103 | static void test_seccomp_sys_fork_on(void) |
| 104 | { |
| 105 | test_seccomp_passed("on", doit_sys_fork); |
| 106 | } |
| 107 | |
| 108 | static void test_seccomp_sys_fork_off(void) |
| 109 | { |
| 110 | test_seccomp_passed("off", doit_sys_fork); |
| 111 | } |
| 112 | #endif |
| 113 | |
| 114 | static int doit_fork(void) |
| 115 | { |
| 116 | int ret = fork(); |
| 117 | if (ret < 0) { |
| 118 | return ret; |
| 119 | } |
| 120 | if (ret == 0) { |
| 121 | _exit(0); |
| 122 | } |
| 123 | return 0; |
| 124 | } |
| 125 | |
| 126 | static void test_seccomp_fork_on_nospawn(void) |
| 127 | { |
| 128 | test_seccomp_killed("on,spawn=deny", doit_fork); |
| 129 | } |
| 130 | |
| 131 | static void test_seccomp_fork_on(void) |
| 132 | { |
| 133 | test_seccomp_passed("on", doit_fork); |
| 134 | } |
| 135 | |
| 136 | static void test_seccomp_fork_off(void) |
| 137 | { |
| 138 | test_seccomp_passed("off", doit_fork); |
| 139 | } |
| 140 | |
| 141 | static void *noop(void *arg) |
| 142 | { |
| 143 | return arg; |
| 144 | } |
| 145 | |
| 146 | static int doit_thread(void) |
| 147 | { |
| 148 | pthread_t th; |
| 149 | int ret = pthread_create(&th, NULL, noop, NULL); |
| 150 | if (ret != 0) { |
| 151 | errno = ret; |
| 152 | return -1; |
| 153 | } else { |
| 154 | pthread_join(th, NULL); |
| 155 | return 0; |
| 156 | } |
| 157 | } |
| 158 | |
| 159 | static void test_seccomp_thread_on(void) |
| 160 | { |
| 161 | test_seccomp_passed("on", doit_thread); |
| 162 | } |
| 163 | |
| 164 | static void test_seccomp_thread_on_nospawn(void) |
| 165 | { |
| 166 | test_seccomp_passed("on,spawn=deny", doit_thread); |
| 167 | } |
| 168 | |
| 169 | static void test_seccomp_thread_off(void) |
| 170 | { |
| 171 | test_seccomp_passed("off", doit_thread); |
| 172 | } |
| 173 | |
| 174 | static int doit_sched(void) |
| 175 | { |
| 176 | struct sched_param param = { .sched_priority = 0 }; |
| 177 | return sched_setscheduler(getpid(), SCHED_OTHER, ¶m); |
| 178 | } |
| 179 | |
| 180 | static void test_seccomp_sched_on_nores(void) |
| 181 | { |
| 182 | test_seccomp_errno("on,resourcecontrol=deny", EPERM, doit_sched); |
| 183 | } |
| 184 | |
| 185 | static void test_seccomp_sched_on(void) |
| 186 | { |
| 187 | test_seccomp_passed("on", doit_sched); |
| 188 | } |
| 189 | |
| 190 | static void test_seccomp_sched_off(void) |
| 191 | { |
| 192 | test_seccomp_passed("off", doit_sched); |
| 193 | } |
| 194 | |
| 195 | static bool can_play_with_seccomp(void) |
| 196 | { |
| 197 | g_autofree char *status = NULL; |
| 198 | g_auto(GStrv) lines = NULL; |
| 199 | size_t i; |
| 200 | |
| 201 | if (!g_file_get_contents("/proc/self/status", &status, NULL, NULL)) { |
| 202 | return false; |
| 203 | } |
| 204 | |
| 205 | lines = g_strsplit(status, "\n", 0); |
| 206 | |
| 207 | for (i = 0; lines[i] != NULL; i++) { |
| 208 | if (g_str_has_prefix(lines[i], "Seccomp:")) { |
| 209 | /* |
| 210 | * "Seccomp: 1" or "Seccomp: 2" indicate we're already |
| 211 | * confined, probably as we're inside a container. In |
| 212 | * this case our tests might get unexpected results, |
| 213 | * so we can't run reliably |
| 214 | */ |
| 215 | if (!strchr(lines[i], '0')) { |
| 216 | return false; |
| 217 | } |
| 218 | |
| 219 | return true; |
| 220 | } |
| 221 | } |
| 222 | |
| 223 | /* Doesn't look like seccomp is enabled in the kernel */ |
| 224 | return false; |
| 225 | } |
| 226 | |
| 227 | int main(int argc, char **argv) |
| 228 | { |
| 229 | g_test_init(&argc, &argv, NULL); |
| 230 | if (can_play_with_seccomp()) { |
| 231 | #ifdef SYS_fork |
| 232 | g_test_add_func("/seccomp/sys-fork/on", |
| 233 | test_seccomp_sys_fork_on); |
| 234 | g_test_add_func("/seccomp/sys-fork/on-nospawn", |
| 235 | test_seccomp_sys_fork_on_nospawn); |
| 236 | g_test_add_func("/seccomp/sys-fork/off", |
| 237 | test_seccomp_sys_fork_off); |
| 238 | #endif |
| 239 | |
| 240 | g_test_add_func("/seccomp/fork/on", |
| 241 | test_seccomp_fork_on); |
| 242 | g_test_add_func("/seccomp/fork/on-nospawn", |
| 243 | test_seccomp_fork_on_nospawn); |
| 244 | g_test_add_func("/seccomp/fork/off", |
| 245 | test_seccomp_fork_off); |
| 246 | |
| 247 | g_test_add_func("/seccomp/thread/on", |
| 248 | test_seccomp_thread_on); |
| 249 | g_test_add_func("/seccomp/thread/on-nospawn", |
| 250 | test_seccomp_thread_on_nospawn); |
| 251 | g_test_add_func("/seccomp/thread/off", |
| 252 | test_seccomp_thread_off); |
| 253 | |
| 254 | if (doit_sched() == 0) { |
| 255 | /* |
| 256 | * musl doesn't impl sched_setscheduler, hence |
| 257 | * we check above if it works first |
| 258 | */ |
| 259 | g_test_add_func("/seccomp/sched/on", |
| 260 | test_seccomp_sched_on); |
| 261 | g_test_add_func("/seccomp/sched/on-nores", |
| 262 | test_seccomp_sched_on_nores); |
| 263 | g_test_add_func("/seccomp/sched/off", |
| 264 | test_seccomp_sched_off); |
| 265 | } |
| 266 | } |
| 267 | return g_test_run(); |
| 268 | } |