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53e1b683 | 1 | /* SPDX-License-Identifier: LGPL-2.1+ */ |
57183d11 LP |
2 | /*** |
3 | This file is part of systemd. | |
4 | ||
5 | Copyright 2014 Lennart Poettering | |
6 | ||
7 | systemd is free software; you can redistribute it and/or modify it | |
8 | under the terms of the GNU Lesser General Public License as published by | |
9 | the Free Software Foundation; either version 2.1 of the License, or | |
10 | (at your option) any later version. | |
11 | ||
12 | systemd is distributed in the hope that it will be useful, but | |
13 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | Lesser General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU Lesser General Public License | |
18 | along with systemd; If not, see <http://www.gnu.org/licenses/>. | |
19 | ***/ | |
20 | ||
a8fbdf54 | 21 | #include <errno.h> |
469830d1 | 22 | #include <linux/seccomp.h> |
57183d11 | 23 | #include <seccomp.h> |
a8fbdf54 | 24 | #include <stddef.h> |
469830d1 | 25 | #include <sys/mman.h> |
d347d902 | 26 | #include <sys/prctl.h> |
469830d1 | 27 | #include <sys/shm.h> |
57183d11 | 28 | |
469830d1 | 29 | #include "af-list.h" |
add00535 | 30 | #include "alloc-util.h" |
a8fbdf54 | 31 | #include "macro.h" |
add00535 | 32 | #include "nsflags.h" |
78e864e5 | 33 | #include "process-util.h" |
cf0fbc49 | 34 | #include "seccomp-util.h" |
b16bd535 | 35 | #include "set.h" |
07630cea | 36 | #include "string-util.h" |
b16bd535 | 37 | #include "strv.h" |
8130926d | 38 | #include "util.h" |
469830d1 LP |
39 | #include "errno-list.h" |
40 | ||
41 | const uint32_t seccomp_local_archs[] = { | |
42 | ||
f2d9751c LP |
43 | /* Note: always list the native arch we are compiled as last, so that users can blacklist seccomp(), but our own calls to it still succeed */ |
44 | ||
45 | #if defined(__x86_64__) && defined(__ILP32__) | |
469830d1 LP |
46 | SCMP_ARCH_X86, |
47 | SCMP_ARCH_X86_64, | |
f2d9751c LP |
48 | SCMP_ARCH_X32, /* native */ |
49 | #elif defined(__x86_64__) && !defined(__ILP32__) | |
50 | SCMP_ARCH_X86, | |
469830d1 | 51 | SCMP_ARCH_X32, |
f2d9751c LP |
52 | SCMP_ARCH_X86_64, /* native */ |
53 | #elif defined(__i386__) | |
54 | SCMP_ARCH_X86, | |
55 | #elif defined(__aarch64__) | |
469830d1 | 56 | SCMP_ARCH_ARM, |
f2d9751c LP |
57 | SCMP_ARCH_AARCH64, /* native */ |
58 | #elif defined(__arm__) | |
59 | SCMP_ARCH_ARM, | |
60 | #elif defined(__mips__) && __BYTE_ORDER == __BIG_ENDIAN && _MIPS_SIM == _MIPS_SIM_ABI32 | |
61 | SCMP_ARCH_MIPSEL, | |
62 | SCMP_ARCH_MIPS, /* native */ | |
63 | #elif defined(__mips__) && __BYTE_ORDER == __LITTLE_ENDIAN && _MIPS_SIM == _MIPS_SIM_ABI32 | |
469830d1 | 64 | SCMP_ARCH_MIPS, |
f2d9751c LP |
65 | SCMP_ARCH_MIPSEL, /* native */ |
66 | #elif defined(__mips__) && __BYTE_ORDER == __BIG_ENDIAN && _MIPS_SIM == _MIPS_SIM_ABI64 | |
67 | SCMP_ARCH_MIPSEL, | |
68 | SCMP_ARCH_MIPS, | |
69 | SCMP_ARCH_MIPSEL64N32, | |
469830d1 | 70 | SCMP_ARCH_MIPS64N32, |
f2d9751c LP |
71 | SCMP_ARCH_MIPSEL64, |
72 | SCMP_ARCH_MIPS64, /* native */ | |
73 | #elif defined(__mips__) && __BYTE_ORDER == __LITTLE_ENDIAN && _MIPS_SIM == _MIPS_SIM_ABI64 | |
74 | SCMP_ARCH_MIPS, | |
469830d1 | 75 | SCMP_ARCH_MIPSEL, |
f2d9751c LP |
76 | SCMP_ARCH_MIPS64N32, |
77 | SCMP_ARCH_MIPSEL64N32, | |
78 | SCMP_ARCH_MIPS64, | |
79 | SCMP_ARCH_MIPSEL64, /* native */ | |
80 | #elif defined(__mips__) && __BYTE_ORDER == __BIG_ENDIAN && _MIPS_SIM == _MIPS_SIM_NABI32 | |
81 | SCMP_ARCH_MIPSEL, | |
82 | SCMP_ARCH_MIPS, | |
469830d1 | 83 | SCMP_ARCH_MIPSEL64, |
f2d9751c | 84 | SCMP_ARCH_MIPS64, |
469830d1 | 85 | SCMP_ARCH_MIPSEL64N32, |
f2d9751c LP |
86 | SCMP_ARCH_MIPS64N32, /* native */ |
87 | #elif defined(__mips__) && __BYTE_ORDER == __LITTLE_ENDIAN && _MIPS_SIM == _MIPS_SIM_NABI32 | |
88 | SCMP_ARCH_MIPS, | |
89 | SCMP_ARCH_MIPSEL, | |
90 | SCMP_ARCH_MIPS64, | |
91 | SCMP_ARCH_MIPSEL64, | |
92 | SCMP_ARCH_MIPS64N32, | |
93 | SCMP_ARCH_MIPSEL64N32, /* native */ | |
94 | #elif defined(__powerpc64__) && __BYTE_ORDER == __BIG_ENDIAN | |
469830d1 | 95 | SCMP_ARCH_PPC, |
469830d1 | 96 | SCMP_ARCH_PPC64LE, |
f2d9751c LP |
97 | SCMP_ARCH_PPC64, /* native */ |
98 | #elif defined(__powerpc64__) && __BYTE_ORDER == __LITTLE_ENDIAN | |
99 | SCMP_ARCH_PPC, | |
100 | SCMP_ARCH_PPC64, | |
101 | SCMP_ARCH_PPC64LE, /* native */ | |
102 | #elif defined(__powerpc__) | |
103 | SCMP_ARCH_PPC, | |
104 | #elif defined(__s390x__) | |
105 | SCMP_ARCH_S390, | |
106 | SCMP_ARCH_S390X, /* native */ | |
107 | #elif defined(__s390__) | |
469830d1 | 108 | SCMP_ARCH_S390, |
469830d1 LP |
109 | #endif |
110 | (uint32_t) -1 | |
111 | }; | |
57183d11 LP |
112 | |
113 | const char* seccomp_arch_to_string(uint32_t c) { | |
aa34055f ZJS |
114 | /* Maintain order used in <seccomp.h>. |
115 | * | |
116 | * Names used here should be the same as those used for ConditionArchitecture=, | |
117 | * except for "subarchitectures" like x32. */ | |
57183d11 | 118 | |
aa34055f ZJS |
119 | switch(c) { |
120 | case SCMP_ARCH_NATIVE: | |
57183d11 | 121 | return "native"; |
aa34055f | 122 | case SCMP_ARCH_X86: |
57183d11 | 123 | return "x86"; |
aa34055f | 124 | case SCMP_ARCH_X86_64: |
57183d11 | 125 | return "x86-64"; |
aa34055f | 126 | case SCMP_ARCH_X32: |
57183d11 | 127 | return "x32"; |
aa34055f | 128 | case SCMP_ARCH_ARM: |
57183d11 | 129 | return "arm"; |
aa34055f ZJS |
130 | case SCMP_ARCH_AARCH64: |
131 | return "arm64"; | |
132 | case SCMP_ARCH_MIPS: | |
133 | return "mips"; | |
134 | case SCMP_ARCH_MIPS64: | |
135 | return "mips64"; | |
136 | case SCMP_ARCH_MIPS64N32: | |
137 | return "mips64-n32"; | |
138 | case SCMP_ARCH_MIPSEL: | |
139 | return "mips-le"; | |
140 | case SCMP_ARCH_MIPSEL64: | |
141 | return "mips64-le"; | |
142 | case SCMP_ARCH_MIPSEL64N32: | |
143 | return "mips64-le-n32"; | |
144 | case SCMP_ARCH_PPC: | |
145 | return "ppc"; | |
146 | case SCMP_ARCH_PPC64: | |
147 | return "ppc64"; | |
148 | case SCMP_ARCH_PPC64LE: | |
149 | return "ppc64-le"; | |
150 | case SCMP_ARCH_S390: | |
6abfd303 | 151 | return "s390"; |
aa34055f | 152 | case SCMP_ARCH_S390X: |
6abfd303 | 153 | return "s390x"; |
aa34055f ZJS |
154 | default: |
155 | return NULL; | |
156 | } | |
57183d11 LP |
157 | } |
158 | ||
159 | int seccomp_arch_from_string(const char *n, uint32_t *ret) { | |
160 | if (!n) | |
161 | return -EINVAL; | |
162 | ||
163 | assert(ret); | |
164 | ||
165 | if (streq(n, "native")) | |
166 | *ret = SCMP_ARCH_NATIVE; | |
167 | else if (streq(n, "x86")) | |
168 | *ret = SCMP_ARCH_X86; | |
169 | else if (streq(n, "x86-64")) | |
170 | *ret = SCMP_ARCH_X86_64; | |
171 | else if (streq(n, "x32")) | |
172 | *ret = SCMP_ARCH_X32; | |
173 | else if (streq(n, "arm")) | |
174 | *ret = SCMP_ARCH_ARM; | |
aa34055f ZJS |
175 | else if (streq(n, "arm64")) |
176 | *ret = SCMP_ARCH_AARCH64; | |
177 | else if (streq(n, "mips")) | |
178 | *ret = SCMP_ARCH_MIPS; | |
179 | else if (streq(n, "mips64")) | |
180 | *ret = SCMP_ARCH_MIPS64; | |
181 | else if (streq(n, "mips64-n32")) | |
182 | *ret = SCMP_ARCH_MIPS64N32; | |
183 | else if (streq(n, "mips-le")) | |
184 | *ret = SCMP_ARCH_MIPSEL; | |
185 | else if (streq(n, "mips64-le")) | |
186 | *ret = SCMP_ARCH_MIPSEL64; | |
187 | else if (streq(n, "mips64-le-n32")) | |
188 | *ret = SCMP_ARCH_MIPSEL64N32; | |
189 | else if (streq(n, "ppc")) | |
190 | *ret = SCMP_ARCH_PPC; | |
191 | else if (streq(n, "ppc64")) | |
192 | *ret = SCMP_ARCH_PPC64; | |
193 | else if (streq(n, "ppc64-le")) | |
194 | *ret = SCMP_ARCH_PPC64LE; | |
6abfd303 HB |
195 | else if (streq(n, "s390")) |
196 | *ret = SCMP_ARCH_S390; | |
197 | else if (streq(n, "s390x")) | |
198 | *ret = SCMP_ARCH_S390X; | |
57183d11 LP |
199 | else |
200 | return -EINVAL; | |
201 | ||
202 | return 0; | |
203 | } | |
e9642be2 | 204 | |
469830d1 | 205 | int seccomp_init_for_arch(scmp_filter_ctx *ret, uint32_t arch, uint32_t default_action) { |
8d7b0c8f LP |
206 | scmp_filter_ctx seccomp; |
207 | int r; | |
208 | ||
469830d1 LP |
209 | /* Much like seccomp_init(), but initializes the filter for one specific architecture only, without affecting |
210 | * any others. Also, turns off the NNP fiddling. */ | |
8d7b0c8f LP |
211 | |
212 | seccomp = seccomp_init(default_action); | |
213 | if (!seccomp) | |
214 | return -ENOMEM; | |
215 | ||
469830d1 LP |
216 | if (arch != SCMP_ARCH_NATIVE && |
217 | arch != seccomp_arch_native()) { | |
218 | ||
1b52793d | 219 | r = seccomp_arch_remove(seccomp, seccomp_arch_native()); |
469830d1 LP |
220 | if (r < 0) |
221 | goto finish; | |
222 | ||
1b52793d | 223 | r = seccomp_arch_add(seccomp, arch); |
469830d1 LP |
224 | if (r < 0) |
225 | goto finish; | |
226 | ||
227 | assert(seccomp_arch_exist(seccomp, arch) >= 0); | |
228 | assert(seccomp_arch_exist(seccomp, SCMP_ARCH_NATIVE) == -EEXIST); | |
229 | assert(seccomp_arch_exist(seccomp, seccomp_arch_native()) == -EEXIST); | |
230 | } else { | |
231 | assert(seccomp_arch_exist(seccomp, SCMP_ARCH_NATIVE) >= 0); | |
232 | assert(seccomp_arch_exist(seccomp, seccomp_arch_native()) >= 0); | |
233 | } | |
234 | ||
235 | r = seccomp_attr_set(seccomp, SCMP_FLTATR_ACT_BADARCH, SCMP_ACT_ALLOW); | |
8d7b0c8f LP |
236 | if (r < 0) |
237 | goto finish; | |
238 | ||
239 | r = seccomp_attr_set(seccomp, SCMP_FLTATR_CTL_NNP, 0); | |
240 | if (r < 0) | |
241 | goto finish; | |
242 | ||
243 | *ret = seccomp; | |
244 | return 0; | |
245 | ||
246 | finish: | |
247 | seccomp_release(seccomp); | |
248 | return r; | |
249 | } | |
250 | ||
d347d902 | 251 | static bool is_basic_seccomp_available(void) { |
4d5bd50a | 252 | return prctl(PR_GET_SECCOMP, 0, 0, 0, 0) >= 0; |
d347d902 FS |
253 | } |
254 | ||
255 | static bool is_seccomp_filter_available(void) { | |
4d5bd50a LP |
256 | return prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, NULL, 0, 0) < 0 && |
257 | errno == EFAULT; | |
d347d902 FS |
258 | } |
259 | ||
83f12b27 | 260 | bool is_seccomp_available(void) { |
83f12b27 | 261 | static int cached_enabled = -1; |
4d5bd50a | 262 | |
83f12b27 | 263 | if (cached_enabled < 0) |
4d5bd50a LP |
264 | cached_enabled = |
265 | is_basic_seccomp_available() && | |
266 | is_seccomp_filter_available(); | |
267 | ||
83f12b27 FS |
268 | return cached_enabled; |
269 | } | |
270 | ||
8130926d | 271 | const SyscallFilterSet syscall_filter_sets[_SYSCALL_FILTER_SET_MAX] = { |
40eb6a80 | 272 | [SYSCALL_FILTER_SET_DEFAULT] = { |
40eb6a80 | 273 | .name = "@default", |
d5efc18b | 274 | .help = "System calls that are always permitted", |
40eb6a80 ZJS |
275 | .value = |
276 | "clock_getres\0" | |
277 | "clock_gettime\0" | |
278 | "clock_nanosleep\0" | |
279 | "execve\0" | |
280 | "exit\0" | |
281 | "exit_group\0" | |
e41b0f42 LP |
282 | "futex\0" |
283 | "get_robust_list\0" | |
284 | "get_thread_area\0" | |
09d3020b DH |
285 | "getegid\0" |
286 | "getegid32\0" | |
287 | "geteuid\0" | |
288 | "geteuid32\0" | |
289 | "getgid\0" | |
290 | "getgid32\0" | |
291 | "getgroups\0" | |
292 | "getgroups32\0" | |
293 | "getpgid\0" | |
294 | "getpgrp\0" | |
295 | "getpid\0" | |
296 | "getppid\0" | |
297 | "getresgid\0" | |
298 | "getresgid32\0" | |
299 | "getresuid\0" | |
300 | "getresuid32\0" | |
40eb6a80 | 301 | "getrlimit\0" /* make sure processes can query stack size and such */ |
09d3020b DH |
302 | "getsid\0" |
303 | "gettid\0" | |
40eb6a80 | 304 | "gettimeofday\0" |
09d3020b DH |
305 | "getuid\0" |
306 | "getuid32\0" | |
e41b0f42 | 307 | "membarrier\0" |
40eb6a80 ZJS |
308 | "nanosleep\0" |
309 | "pause\0" | |
4c3a9176 | 310 | "prlimit64\0" |
e41b0f42 | 311 | "restart_syscall\0" |
40eb6a80 | 312 | "rt_sigreturn\0" |
8f44de08 | 313 | "sched_yield\0" |
e41b0f42 LP |
314 | "set_robust_list\0" |
315 | "set_thread_area\0" | |
316 | "set_tid_address\0" | |
ce5faeac | 317 | "set_tls\0" |
40eb6a80 ZJS |
318 | "sigreturn\0" |
319 | "time\0" | |
4c3a9176 | 320 | "ugetrlimit\0" |
40eb6a80 | 321 | }, |
44898c53 LP |
322 | [SYSCALL_FILTER_SET_AIO] = { |
323 | .name = "@aio", | |
324 | .help = "Asynchronous IO", | |
325 | .value = | |
326 | "io_cancel\0" | |
327 | "io_destroy\0" | |
328 | "io_getevents\0" | |
329 | "io_setup\0" | |
330 | "io_submit\0" | |
331 | }, | |
133ddbbe | 332 | [SYSCALL_FILTER_SET_BASIC_IO] = { |
133ddbbe | 333 | .name = "@basic-io", |
d5efc18b | 334 | .help = "Basic IO", |
133ddbbe | 335 | .value = |
648a0ed0 | 336 | "_llseek\0" |
133ddbbe | 337 | "close\0" |
648a0ed0 | 338 | "dup\0" |
133ddbbe LP |
339 | "dup2\0" |
340 | "dup3\0" | |
133ddbbe LP |
341 | "lseek\0" |
342 | "pread64\0" | |
343 | "preadv\0" | |
44898c53 | 344 | "preadv2\0" |
133ddbbe LP |
345 | "pwrite64\0" |
346 | "pwritev\0" | |
44898c53 | 347 | "pwritev2\0" |
133ddbbe LP |
348 | "read\0" |
349 | "readv\0" | |
350 | "write\0" | |
351 | "writev\0" | |
352 | }, | |
44898c53 LP |
353 | [SYSCALL_FILTER_SET_CHOWN] = { |
354 | .name = "@chown", | |
355 | .help = "Change ownership of files and directories", | |
356 | .value = | |
357 | "chown\0" | |
358 | "chown32\0" | |
359 | "fchown\0" | |
360 | "fchown32\0" | |
361 | "fchownat\0" | |
362 | "lchown\0" | |
363 | "lchown32\0" | |
364 | }, | |
8130926d | 365 | [SYSCALL_FILTER_SET_CLOCK] = { |
8130926d | 366 | .name = "@clock", |
d5efc18b | 367 | .help = "Change the system time", |
201c1cc2 TM |
368 | .value = |
369 | "adjtimex\0" | |
1f9ac68b LP |
370 | "clock_adjtime\0" |
371 | "clock_settime\0" | |
201c1cc2 | 372 | "settimeofday\0" |
1f9ac68b | 373 | "stime\0" |
8130926d LP |
374 | }, |
375 | [SYSCALL_FILTER_SET_CPU_EMULATION] = { | |
8130926d | 376 | .name = "@cpu-emulation", |
d5efc18b | 377 | .help = "System calls for CPU emulation functionality", |
1f9ac68b LP |
378 | .value = |
379 | "modify_ldt\0" | |
380 | "subpage_prot\0" | |
381 | "switch_endian\0" | |
382 | "vm86\0" | |
383 | "vm86old\0" | |
8130926d LP |
384 | }, |
385 | [SYSCALL_FILTER_SET_DEBUG] = { | |
8130926d | 386 | .name = "@debug", |
d5efc18b | 387 | .help = "Debugging, performance monitoring and tracing functionality", |
1f9ac68b LP |
388 | .value = |
389 | "lookup_dcookie\0" | |
390 | "perf_event_open\0" | |
391 | "process_vm_readv\0" | |
392 | "process_vm_writev\0" | |
393 | "ptrace\0" | |
394 | "rtas\0" | |
8130926d | 395 | #ifdef __NR_s390_runtime_instr |
1f9ac68b | 396 | "s390_runtime_instr\0" |
8130926d | 397 | #endif |
1f9ac68b | 398 | "sys_debug_setcontext\0" |
8130926d | 399 | }, |
1a1b13c9 LP |
400 | [SYSCALL_FILTER_SET_FILE_SYSTEM] = { |
401 | .name = "@file-system", | |
402 | .help = "File system operations", | |
403 | .value = | |
404 | "access\0" | |
405 | "chdir\0" | |
406 | "chmod\0" | |
407 | "close\0" | |
408 | "creat\0" | |
409 | "faccessat\0" | |
410 | "fallocate\0" | |
411 | "fchdir\0" | |
412 | "fchmod\0" | |
413 | "fchmodat\0" | |
1a1b13c9 | 414 | "fcntl\0" |
ceaa6aa7 | 415 | "fcntl64\0" |
1a1b13c9 LP |
416 | "fgetxattr\0" |
417 | "flistxattr\0" | |
ceaa6aa7 | 418 | "fremovexattr\0" |
1a1b13c9 | 419 | "fsetxattr\0" |
1a1b13c9 | 420 | "fstat\0" |
ceaa6aa7 | 421 | "fstat64\0" |
1a1b13c9 | 422 | "fstatat64\0" |
1a1b13c9 | 423 | "fstatfs\0" |
ceaa6aa7 | 424 | "fstatfs64\0" |
1a1b13c9 | 425 | "ftruncate\0" |
ceaa6aa7 | 426 | "ftruncate64\0" |
1a1b13c9 LP |
427 | "futimesat\0" |
428 | "getcwd\0" | |
1a1b13c9 | 429 | "getdents\0" |
ceaa6aa7 | 430 | "getdents64\0" |
1a1b13c9 LP |
431 | "getxattr\0" |
432 | "inotify_add_watch\0" | |
ceaa6aa7 | 433 | "inotify_init\0" |
1a1b13c9 LP |
434 | "inotify_init1\0" |
435 | "inotify_rm_watch\0" | |
436 | "lgetxattr\0" | |
437 | "link\0" | |
438 | "linkat\0" | |
439 | "listxattr\0" | |
440 | "llistxattr\0" | |
441 | "lremovexattr\0" | |
442 | "lsetxattr\0" | |
1a1b13c9 | 443 | "lstat\0" |
ceaa6aa7 | 444 | "lstat64\0" |
1a1b13c9 LP |
445 | "mkdir\0" |
446 | "mkdirat\0" | |
447 | "mknod\0" | |
448 | "mknodat\0" | |
1a1b13c9 | 449 | "mmap\0" |
ceaa6aa7 | 450 | "mmap2\0" |
7961116e | 451 | "munmap\0" |
1a1b13c9 | 452 | "newfstatat\0" |
ceaa6aa7 LP |
453 | "oldfstat\0" |
454 | "oldlstat\0" | |
455 | "oldstat\0" | |
1a1b13c9 LP |
456 | "open\0" |
457 | "openat\0" | |
458 | "readlink\0" | |
459 | "readlinkat\0" | |
460 | "removexattr\0" | |
461 | "rename\0" | |
1a1b13c9 | 462 | "renameat\0" |
ceaa6aa7 | 463 | "renameat2\0" |
1a1b13c9 LP |
464 | "rmdir\0" |
465 | "setxattr\0" | |
1a1b13c9 | 466 | "stat\0" |
ceaa6aa7 | 467 | "stat64\0" |
1a1b13c9 | 468 | "statfs\0" |
ceaa6aa7 | 469 | "statfs64\0" |
8e6a7a8b | 470 | #ifdef __NR_statx |
a4135a74 | 471 | "statx\0" |
ceaa6aa7 | 472 | #endif |
1a1b13c9 LP |
473 | "symlink\0" |
474 | "symlinkat\0" | |
1a1b13c9 | 475 | "truncate\0" |
ceaa6aa7 | 476 | "truncate64\0" |
1a1b13c9 LP |
477 | "unlink\0" |
478 | "unlinkat\0" | |
ceaa6aa7 | 479 | "utime\0" |
1a1b13c9 LP |
480 | "utimensat\0" |
481 | "utimes\0" | |
482 | }, | |
8130926d | 483 | [SYSCALL_FILTER_SET_IO_EVENT] = { |
8130926d | 484 | .name = "@io-event", |
d5efc18b | 485 | .help = "Event loop system calls", |
201c1cc2 TM |
486 | .value = |
487 | "_newselect\0" | |
201c1cc2 | 488 | "epoll_create\0" |
215728ff | 489 | "epoll_create1\0" |
201c1cc2 TM |
490 | "epoll_ctl\0" |
491 | "epoll_ctl_old\0" | |
492 | "epoll_pwait\0" | |
493 | "epoll_wait\0" | |
494 | "epoll_wait_old\0" | |
201c1cc2 | 495 | "eventfd\0" |
215728ff | 496 | "eventfd2\0" |
201c1cc2 TM |
497 | "poll\0" |
498 | "ppoll\0" | |
499 | "pselect6\0" | |
500 | "select\0" | |
8130926d LP |
501 | }, |
502 | [SYSCALL_FILTER_SET_IPC] = { | |
8130926d | 503 | .name = "@ipc", |
d5efc18b ZJS |
504 | .help = "SysV IPC, POSIX Message Queues or other IPC", |
505 | .value = | |
506 | "ipc\0" | |
cd5bfd7e | 507 | "memfd_create\0" |
201c1cc2 TM |
508 | "mq_getsetattr\0" |
509 | "mq_notify\0" | |
510 | "mq_open\0" | |
511 | "mq_timedreceive\0" | |
512 | "mq_timedsend\0" | |
513 | "mq_unlink\0" | |
514 | "msgctl\0" | |
515 | "msgget\0" | |
516 | "msgrcv\0" | |
517 | "msgsnd\0" | |
cd5bfd7e | 518 | "pipe\0" |
215728ff | 519 | "pipe2\0" |
201c1cc2 TM |
520 | "process_vm_readv\0" |
521 | "process_vm_writev\0" | |
522 | "semctl\0" | |
523 | "semget\0" | |
524 | "semop\0" | |
525 | "semtimedop\0" | |
526 | "shmat\0" | |
527 | "shmctl\0" | |
528 | "shmdt\0" | |
529 | "shmget\0" | |
8130926d LP |
530 | }, |
531 | [SYSCALL_FILTER_SET_KEYRING] = { | |
8130926d | 532 | .name = "@keyring", |
d5efc18b | 533 | .help = "Kernel keyring access", |
1f9ac68b LP |
534 | .value = |
535 | "add_key\0" | |
536 | "keyctl\0" | |
537 | "request_key\0" | |
8130926d | 538 | }, |
cd0ddf6f LP |
539 | [SYSCALL_FILTER_SET_MEMLOCK] = { |
540 | .name = "@memlock", | |
541 | .help = "Memory locking control", | |
542 | .value = | |
543 | "mlock\0" | |
544 | "mlock2\0" | |
545 | "mlockall\0" | |
546 | "munlock\0" | |
547 | "munlockall\0" | |
548 | }, | |
8130926d | 549 | [SYSCALL_FILTER_SET_MODULE] = { |
8130926d | 550 | .name = "@module", |
d5efc18b | 551 | .help = "Loading and unloading of kernel modules", |
201c1cc2 | 552 | .value = |
201c1cc2 TM |
553 | "delete_module\0" |
554 | "finit_module\0" | |
555 | "init_module\0" | |
8130926d LP |
556 | }, |
557 | [SYSCALL_FILTER_SET_MOUNT] = { | |
8130926d | 558 | .name = "@mount", |
d5efc18b | 559 | .help = "Mounting and unmounting of file systems", |
201c1cc2 TM |
560 | .value = |
561 | "chroot\0" | |
562 | "mount\0" | |
201c1cc2 | 563 | "pivot_root\0" |
201c1cc2 | 564 | "umount\0" |
215728ff | 565 | "umount2\0" |
8130926d LP |
566 | }, |
567 | [SYSCALL_FILTER_SET_NETWORK_IO] = { | |
8130926d | 568 | .name = "@network-io", |
d5efc18b | 569 | .help = "Network or Unix socket IO, should not be needed if not network facing", |
201c1cc2 | 570 | .value = |
201c1cc2 | 571 | "accept\0" |
215728ff | 572 | "accept4\0" |
201c1cc2 TM |
573 | "bind\0" |
574 | "connect\0" | |
575 | "getpeername\0" | |
576 | "getsockname\0" | |
577 | "getsockopt\0" | |
578 | "listen\0" | |
579 | "recv\0" | |
580 | "recvfrom\0" | |
581 | "recvmmsg\0" | |
582 | "recvmsg\0" | |
583 | "send\0" | |
584 | "sendmmsg\0" | |
585 | "sendmsg\0" | |
586 | "sendto\0" | |
587 | "setsockopt\0" | |
588 | "shutdown\0" | |
589 | "socket\0" | |
590 | "socketcall\0" | |
591 | "socketpair\0" | |
8130926d LP |
592 | }, |
593 | [SYSCALL_FILTER_SET_OBSOLETE] = { | |
d5efc18b | 594 | /* some unknown even to libseccomp */ |
8130926d | 595 | .name = "@obsolete", |
d5efc18b | 596 | .help = "Unusual, obsolete or unimplemented system calls", |
201c1cc2 TM |
597 | .value = |
598 | "_sysctl\0" | |
599 | "afs_syscall\0" | |
802fa07a | 600 | "bdflush\0" |
201c1cc2 | 601 | "break\0" |
1f9ac68b | 602 | "create_module\0" |
201c1cc2 TM |
603 | "ftime\0" |
604 | "get_kernel_syms\0" | |
201c1cc2 TM |
605 | "getpmsg\0" |
606 | "gtty\0" | |
7e0c3b8f | 607 | "idle\0" |
201c1cc2 | 608 | "lock\0" |
201c1cc2 | 609 | "mpx\0" |
201c1cc2 TM |
610 | "prof\0" |
611 | "profil\0" | |
201c1cc2 TM |
612 | "putpmsg\0" |
613 | "query_module\0" | |
201c1cc2 TM |
614 | "security\0" |
615 | "sgetmask\0" | |
616 | "ssetmask\0" | |
617 | "stty\0" | |
1f9ac68b | 618 | "sysfs\0" |
201c1cc2 TM |
619 | "tuxcall\0" |
620 | "ulimit\0" | |
621 | "uselib\0" | |
1f9ac68b | 622 | "ustat\0" |
201c1cc2 | 623 | "vserver\0" |
8130926d LP |
624 | }, |
625 | [SYSCALL_FILTER_SET_PRIVILEGED] = { | |
8130926d | 626 | .name = "@privileged", |
d5efc18b | 627 | .help = "All system calls which need super-user capabilities", |
201c1cc2 | 628 | .value = |
44898c53 | 629 | "@chown\0" |
201c1cc2 TM |
630 | "@clock\0" |
631 | "@module\0" | |
632 | "@raw-io\0" | |
af0f047b LP |
633 | "@reboot\0" |
634 | "@swap\0" | |
215728ff | 635 | "_sysctl\0" |
201c1cc2 | 636 | "acct\0" |
201c1cc2 | 637 | "bpf\0" |
1f9ac68b | 638 | "capset\0" |
201c1cc2 | 639 | "chroot\0" |
201c1cc2 TM |
640 | "nfsservctl\0" |
641 | "pivot_root\0" | |
642 | "quotactl\0" | |
201c1cc2 | 643 | "setdomainname\0" |
201c1cc2 | 644 | "setfsuid\0" |
215728ff | 645 | "setfsuid32\0" |
201c1cc2 | 646 | "setgroups\0" |
215728ff | 647 | "setgroups32\0" |
201c1cc2 | 648 | "sethostname\0" |
201c1cc2 | 649 | "setresuid\0" |
215728ff | 650 | "setresuid32\0" |
201c1cc2 | 651 | "setreuid\0" |
215728ff | 652 | "setreuid32\0" |
201c1cc2 | 653 | "setuid\0" |
215728ff | 654 | "setuid32\0" |
201c1cc2 | 655 | "vhangup\0" |
8130926d LP |
656 | }, |
657 | [SYSCALL_FILTER_SET_PROCESS] = { | |
8130926d | 658 | .name = "@process", |
d5efc18b | 659 | .help = "Process control, execution, namespaceing operations", |
201c1cc2 TM |
660 | .value = |
661 | "arch_prctl\0" | |
09d3020b | 662 | "capget\0" /* Able to query arbitrary processes */ |
201c1cc2 | 663 | "clone\0" |
201c1cc2 TM |
664 | "execveat\0" |
665 | "fork\0" | |
b887d2eb | 666 | "getrusage\0" |
201c1cc2 TM |
667 | "kill\0" |
668 | "prctl\0" | |
b887d2eb LP |
669 | "rt_sigqueueinfo\0" |
670 | "rt_tgsigqueueinfo\0" | |
201c1cc2 TM |
671 | "setns\0" |
672 | "tgkill\0" | |
b887d2eb | 673 | "times\0" |
201c1cc2 TM |
674 | "tkill\0" |
675 | "unshare\0" | |
676 | "vfork\0" | |
b887d2eb LP |
677 | "wait4\0" |
678 | "waitid\0" | |
679 | "waitpid\0" | |
8130926d LP |
680 | }, |
681 | [SYSCALL_FILTER_SET_RAW_IO] = { | |
8130926d | 682 | .name = "@raw-io", |
d5efc18b | 683 | .help = "Raw I/O port access", |
201c1cc2 TM |
684 | .value = |
685 | "ioperm\0" | |
686 | "iopl\0" | |
1f9ac68b | 687 | "pciconfig_iobase\0" |
201c1cc2 TM |
688 | "pciconfig_read\0" |
689 | "pciconfig_write\0" | |
8130926d | 690 | #ifdef __NR_s390_pci_mmio_read |
201c1cc2 | 691 | "s390_pci_mmio_read\0" |
8130926d LP |
692 | #endif |
693 | #ifdef __NR_s390_pci_mmio_write | |
201c1cc2 | 694 | "s390_pci_mmio_write\0" |
8130926d LP |
695 | #endif |
696 | }, | |
bd2ab3f4 LP |
697 | [SYSCALL_FILTER_SET_REBOOT] = { |
698 | .name = "@reboot", | |
699 | .help = "Reboot and reboot preparation/kexec", | |
700 | .value = | |
bd2ab3f4 | 701 | "kexec_file_load\0" |
e59608fa | 702 | "kexec_load\0" |
bd2ab3f4 LP |
703 | "reboot\0" |
704 | }, | |
133ddbbe | 705 | [SYSCALL_FILTER_SET_RESOURCES] = { |
133ddbbe | 706 | .name = "@resources", |
58a8f68b | 707 | .help = "Alter resource settings", |
133ddbbe | 708 | .value = |
0963c053 LP |
709 | "ioprio_set\0" |
710 | "mbind\0" | |
711 | "migrate_pages\0" | |
712 | "move_pages\0" | |
713 | "nice\0" | |
0963c053 LP |
714 | "sched_setaffinity\0" |
715 | "sched_setattr\0" | |
133ddbbe LP |
716 | "sched_setparam\0" |
717 | "sched_setscheduler\0" | |
0963c053 | 718 | "set_mempolicy\0" |
133ddbbe LP |
719 | "setpriority\0" |
720 | "setrlimit\0" | |
133ddbbe | 721 | }, |
6eaaeee9 LP |
722 | [SYSCALL_FILTER_SET_SETUID] = { |
723 | .name = "@setuid", | |
724 | .help = "Operations for changing user/group credentials", | |
725 | .value = | |
6eaaeee9 | 726 | "setgid\0" |
215728ff | 727 | "setgid32\0" |
6eaaeee9 | 728 | "setgroups\0" |
215728ff | 729 | "setgroups32\0" |
6eaaeee9 | 730 | "setregid\0" |
215728ff | 731 | "setregid32\0" |
6eaaeee9 | 732 | "setresgid\0" |
215728ff | 733 | "setresgid32\0" |
6eaaeee9 | 734 | "setresuid\0" |
215728ff | 735 | "setresuid32\0" |
6eaaeee9 | 736 | "setreuid\0" |
215728ff | 737 | "setreuid32\0" |
6eaaeee9 | 738 | "setuid\0" |
215728ff | 739 | "setuid32\0" |
6eaaeee9 | 740 | }, |
cd0ddf6f LP |
741 | [SYSCALL_FILTER_SET_SIGNAL] = { |
742 | .name = "@signal", | |
743 | .help = "Process signal handling", | |
744 | .value = | |
745 | "rt_sigaction\0" | |
746 | "rt_sigpending\0" | |
747 | "rt_sigprocmask\0" | |
748 | "rt_sigsuspend\0" | |
749 | "rt_sigtimedwait\0" | |
750 | "sigaction\0" | |
751 | "sigaltstack\0" | |
752 | "signal\0" | |
753 | "signalfd\0" | |
754 | "signalfd4\0" | |
755 | "sigpending\0" | |
756 | "sigprocmask\0" | |
757 | "sigsuspend\0" | |
758 | }, | |
bd2ab3f4 LP |
759 | [SYSCALL_FILTER_SET_SWAP] = { |
760 | .name = "@swap", | |
761 | .help = "Enable/disable swap devices", | |
762 | .value = | |
763 | "swapoff\0" | |
764 | "swapon\0" | |
765 | }, | |
44898c53 LP |
766 | [SYSCALL_FILTER_SET_SYNC] = { |
767 | .name = "@sync", | |
768 | .help = "Synchronize files and memory to storage", | |
769 | .value = | |
770 | "fdatasync\0" | |
771 | "fsync\0" | |
772 | "msync\0" | |
773 | "sync\0" | |
774 | "sync_file_range\0" | |
775 | "syncfs\0" | |
776 | }, | |
cd0ddf6f LP |
777 | [SYSCALL_FILTER_SET_TIMER] = { |
778 | .name = "@timer", | |
779 | .help = "Schedule operations by time", | |
780 | .value = | |
781 | "alarm\0" | |
782 | "getitimer\0" | |
783 | "setitimer\0" | |
784 | "timer_create\0" | |
785 | "timer_delete\0" | |
786 | "timer_getoverrun\0" | |
787 | "timer_gettime\0" | |
788 | "timer_settime\0" | |
789 | "timerfd_create\0" | |
790 | "timerfd_gettime\0" | |
791 | "timerfd_settime\0" | |
792 | "times\0" | |
793 | }, | |
201c1cc2 | 794 | }; |
8130926d LP |
795 | |
796 | const SyscallFilterSet *syscall_filter_set_find(const char *name) { | |
797 | unsigned i; | |
798 | ||
799 | if (isempty(name) || name[0] != '@') | |
800 | return NULL; | |
801 | ||
802 | for (i = 0; i < _SYSCALL_FILTER_SET_MAX; i++) | |
803 | if (streq(syscall_filter_sets[i].name, name)) | |
804 | return syscall_filter_sets + i; | |
805 | ||
806 | return NULL; | |
807 | } | |
808 | ||
960e4569 | 809 | static int seccomp_add_syscall_filter_set(scmp_filter_ctx seccomp, const SyscallFilterSet *set, uint32_t action, char **exclude); |
69b1b241 | 810 | |
960e4569 | 811 | int seccomp_add_syscall_filter_item(scmp_filter_ctx *seccomp, const char *name, uint32_t action, char **exclude) { |
69b1b241 LP |
812 | int r; |
813 | ||
814 | assert(seccomp); | |
815 | assert(name); | |
816 | ||
960e4569 LP |
817 | if (strv_contains(exclude, name)) |
818 | return 0; | |
819 | ||
69b1b241 LP |
820 | if (name[0] == '@') { |
821 | const SyscallFilterSet *other; | |
822 | ||
823 | other = syscall_filter_set_find(name); | |
cff7bff8 LP |
824 | if (!other) { |
825 | log_debug("Filter set %s is not known!", name); | |
69b1b241 | 826 | return -EINVAL; |
cff7bff8 | 827 | } |
69b1b241 | 828 | |
960e4569 | 829 | r = seccomp_add_syscall_filter_set(seccomp, other, action, exclude); |
69b1b241 LP |
830 | if (r < 0) |
831 | return r; | |
832 | } else { | |
833 | int id; | |
834 | ||
835 | id = seccomp_syscall_resolve_name(name); | |
cff7bff8 | 836 | if (id == __NR_SCMP_ERROR) { |
ff217dc3 LP |
837 | log_debug("System call %s is not known, ignoring.", name); |
838 | return 0; | |
cff7bff8 | 839 | } |
69b1b241 LP |
840 | |
841 | r = seccomp_rule_add_exact(seccomp, action, id, 0); | |
842 | if (r < 0) | |
843 | /* If the system call is not known on this architecture, then that's fine, let's ignore it */ | |
844 | log_debug_errno(r, "Failed to add rule for system call %s() / %d, ignoring: %m", name, id); | |
845 | } | |
846 | ||
847 | return 0; | |
848 | } | |
849 | ||
469830d1 LP |
850 | static int seccomp_add_syscall_filter_set( |
851 | scmp_filter_ctx seccomp, | |
469830d1 | 852 | const SyscallFilterSet *set, |
960e4569 LP |
853 | uint32_t action, |
854 | char **exclude) { | |
469830d1 | 855 | |
8130926d LP |
856 | const char *sys; |
857 | int r; | |
858 | ||
859 | assert(seccomp); | |
860 | assert(set); | |
861 | ||
862 | NULSTR_FOREACH(sys, set->value) { | |
960e4569 | 863 | r = seccomp_add_syscall_filter_item(seccomp, sys, action, exclude); |
69b1b241 LP |
864 | if (r < 0) |
865 | return r; | |
469830d1 LP |
866 | } |
867 | ||
868 | return 0; | |
869 | } | |
870 | ||
871 | int seccomp_load_syscall_filter_set(uint32_t default_action, const SyscallFilterSet *set, uint32_t action) { | |
872 | uint32_t arch; | |
873 | int r; | |
874 | ||
875 | assert(set); | |
876 | ||
877 | /* The one-stop solution: allocate a seccomp object, add the specified filter to it, and apply it. Once for | |
878 | * earch local arch. */ | |
879 | ||
880 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { | |
881 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
882 | ||
883 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); | |
884 | ||
885 | r = seccomp_init_for_arch(&seccomp, arch, default_action); | |
8130926d LP |
886 | if (r < 0) |
887 | return r; | |
469830d1 | 888 | |
960e4569 | 889 | r = seccomp_add_syscall_filter_set(seccomp, set, action, NULL); |
469830d1 LP |
890 | if (r < 0) { |
891 | log_debug_errno(r, "Failed to add filter set, ignoring: %m"); | |
892 | continue; | |
893 | } | |
894 | ||
895 | r = seccomp_load(seccomp); | |
896 | if (IN_SET(r, -EPERM, -EACCES)) | |
897 | return r; | |
898 | if (r < 0) | |
899 | log_debug_errno(r, "Failed to install filter set for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
8130926d LP |
900 | } |
901 | ||
902 | return 0; | |
903 | } | |
a3be2849 | 904 | |
8cfa775f | 905 | int seccomp_load_syscall_filter_set_raw(uint32_t default_action, Hashmap* set, uint32_t action) { |
469830d1 | 906 | uint32_t arch; |
a3be2849 LP |
907 | int r; |
908 | ||
469830d1 LP |
909 | /* Similar to seccomp_load_syscall_filter_set(), but takes a raw Set* of syscalls, instead of a |
910 | * SyscallFilterSet* table. */ | |
a3be2849 | 911 | |
8cfa775f | 912 | if (hashmap_isempty(set) && default_action == SCMP_ACT_ALLOW) |
469830d1 | 913 | return 0; |
a3be2849 | 914 | |
469830d1 LP |
915 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { |
916 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
917 | Iterator i; | |
8cfa775f | 918 | void *id, *val; |
a3be2849 | 919 | |
469830d1 | 920 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); |
a3be2849 | 921 | |
469830d1 LP |
922 | r = seccomp_init_for_arch(&seccomp, arch, default_action); |
923 | if (r < 0) | |
924 | return r; | |
a3be2849 | 925 | |
8cfa775f YW |
926 | HASHMAP_FOREACH_KEY(val, id, set, i) { |
927 | uint32_t a = action; | |
928 | int e = PTR_TO_INT(val); | |
929 | ||
930 | if (action != SCMP_ACT_ALLOW && e >= 0) | |
931 | a = SCMP_ACT_ERRNO(e); | |
932 | ||
933 | r = seccomp_rule_add_exact(seccomp, a, PTR_TO_INT(id) - 1, 0); | |
469830d1 LP |
934 | if (r < 0) { |
935 | /* If the system call is not known on this architecture, then that's fine, let's ignore it */ | |
936 | _cleanup_free_ char *n = NULL; | |
937 | ||
5c19ff79 | 938 | n = seccomp_syscall_resolve_num_arch(SCMP_ARCH_NATIVE, PTR_TO_INT(id) - 1); |
e7854c46 | 939 | log_debug_errno(r, "Failed to add rule for system call %s() / %d, ignoring: %m", strna(n), PTR_TO_INT(id) - 1); |
469830d1 LP |
940 | } |
941 | } | |
942 | ||
943 | r = seccomp_load(seccomp); | |
944 | if (IN_SET(r, -EPERM, -EACCES)) | |
945 | return r; | |
946 | if (r < 0) | |
947 | log_debug_errno(r, "Failed to install filter set for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
948 | } | |
949 | ||
950 | return 0; | |
add00535 LP |
951 | } |
952 | ||
13d92c63 | 953 | int seccomp_parse_syscall_filter_full( |
898748d8 YW |
954 | const char *name, |
955 | int errno_num, | |
956 | Hashmap *filter, | |
13d92c63 | 957 | SeccompParseFlags flags, |
898748d8 YW |
958 | const char *unit, |
959 | const char *filename, | |
960 | unsigned line) { | |
961 | ||
962 | int r; | |
963 | ||
964 | assert(name); | |
965 | assert(filter); | |
966 | ||
967 | if (name[0] == '@') { | |
968 | const SyscallFilterSet *set; | |
969 | const char *i; | |
970 | ||
971 | set = syscall_filter_set_find(name); | |
972 | if (!set) { | |
13d92c63 | 973 | if (!(flags & SECCOMP_PARSE_PERMISSIVE)) |
898748d8 | 974 | return -EINVAL; |
13d92c63 LP |
975 | |
976 | log_syntax(unit, flags & SECCOMP_PARSE_LOG ? LOG_WARNING : LOG_DEBUG, filename, line, 0, | |
977 | "Unknown system call group, ignoring: %s", name); | |
978 | return 0; | |
898748d8 YW |
979 | } |
980 | ||
981 | NULSTR_FOREACH(i, set->value) { | |
13d92c63 LP |
982 | /* Call ourselves again, for the group to parse. Note that we downgrade logging here (i.e. take |
983 | * away the SECCOMP_PARSE_LOG flag) since any issues in the group table are our own problem, | |
984 | * not a problem in user configuration data and we shouldn't pretend otherwise by complaining | |
985 | * about them. */ | |
986 | r = seccomp_parse_syscall_filter_full(i, errno_num, filter, flags &~ SECCOMP_PARSE_LOG, unit, filename, line); | |
898748d8 YW |
987 | if (r < 0) |
988 | return r; | |
989 | } | |
990 | } else { | |
991 | int id; | |
992 | ||
993 | id = seccomp_syscall_resolve_name(name); | |
994 | if (id == __NR_SCMP_ERROR) { | |
13d92c63 | 995 | if (!(flags & SECCOMP_PARSE_PERMISSIVE)) |
898748d8 | 996 | return -EINVAL; |
13d92c63 LP |
997 | |
998 | log_syntax(unit, flags & SECCOMP_PARSE_LOG ? LOG_WARNING : LOG_DEBUG, filename, line, 0, | |
999 | "Failed to parse system call, ignoring: %s", name); | |
1000 | return 0; | |
898748d8 YW |
1001 | } |
1002 | ||
1003 | /* If we previously wanted to forbid a syscall and now | |
1004 | * we want to allow it, then remove it from the list. */ | |
13d92c63 | 1005 | if (!(flags & SECCOMP_PARSE_INVERT) == !!(flags & SECCOMP_PARSE_WHITELIST)) { |
898748d8 YW |
1006 | r = hashmap_put(filter, INT_TO_PTR(id + 1), INT_TO_PTR(errno_num)); |
1007 | if (r < 0) | |
13d92c63 | 1008 | return flags & SECCOMP_PARSE_LOG ? log_oom() : -ENOMEM; |
898748d8 YW |
1009 | } else |
1010 | (void) hashmap_remove(filter, INT_TO_PTR(id + 1)); | |
1011 | } | |
1012 | ||
1013 | return 0; | |
1014 | } | |
1015 | ||
add00535 | 1016 | int seccomp_restrict_namespaces(unsigned long retain) { |
469830d1 | 1017 | uint32_t arch; |
add00535 LP |
1018 | int r; |
1019 | ||
f1d34068 | 1020 | if (DEBUG_LOGGING) { |
add00535 LP |
1021 | _cleanup_free_ char *s = NULL; |
1022 | ||
1023 | (void) namespace_flag_to_string_many(retain, &s); | |
1024 | log_debug("Restricting namespace to: %s.", strna(s)); | |
1025 | } | |
1026 | ||
1027 | /* NOOP? */ | |
1028 | if ((retain & NAMESPACE_FLAGS_ALL) == NAMESPACE_FLAGS_ALL) | |
1029 | return 0; | |
1030 | ||
469830d1 LP |
1031 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { |
1032 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
1033 | unsigned i; | |
add00535 | 1034 | |
469830d1 LP |
1035 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); |
1036 | ||
1037 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); | |
1038 | if (r < 0) | |
1039 | return r; | |
1040 | ||
1041 | if ((retain & NAMESPACE_FLAGS_ALL) == 0) | |
1042 | /* If every single kind of namespace shall be prohibited, then let's block the whole setns() syscall | |
1043 | * altogether. */ | |
1044 | r = seccomp_rule_add_exact( | |
1045 | seccomp, | |
1046 | SCMP_ACT_ERRNO(EPERM), | |
1047 | SCMP_SYS(setns), | |
1048 | 0); | |
1049 | else | |
1050 | /* Otherwise, block only the invocations with the appropriate flags in the loop below, but also the | |
1051 | * special invocation with a zero flags argument, right here. */ | |
1052 | r = seccomp_rule_add_exact( | |
1053 | seccomp, | |
1054 | SCMP_ACT_ERRNO(EPERM), | |
1055 | SCMP_SYS(setns), | |
1056 | 1, | |
1057 | SCMP_A1(SCMP_CMP_EQ, 0)); | |
1058 | if (r < 0) { | |
1059 | log_debug_errno(r, "Failed to add setns() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1060 | continue; | |
1061 | } | |
1062 | ||
1063 | for (i = 0; namespace_flag_map[i].name; i++) { | |
1064 | unsigned long f; | |
1065 | ||
1066 | f = namespace_flag_map[i].flag; | |
1067 | if ((retain & f) == f) { | |
1068 | log_debug("Permitting %s.", namespace_flag_map[i].name); | |
1069 | continue; | |
1070 | } | |
1071 | ||
1072 | log_debug("Blocking %s.", namespace_flag_map[i].name); | |
1073 | ||
1074 | r = seccomp_rule_add_exact( | |
1075 | seccomp, | |
1076 | SCMP_ACT_ERRNO(EPERM), | |
1077 | SCMP_SYS(unshare), | |
1078 | 1, | |
1079 | SCMP_A0(SCMP_CMP_MASKED_EQ, f, f)); | |
1080 | if (r < 0) { | |
1081 | log_debug_errno(r, "Failed to add unshare() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1082 | break; | |
1083 | } | |
1084 | ||
511ceb1f ZJS |
1085 | /* On s390/s390x the first two parameters to clone are switched */ |
1086 | if (!IN_SET(arch, SCMP_ARCH_S390, SCMP_ARCH_S390X)) | |
ae9d60ce LP |
1087 | r = seccomp_rule_add_exact( |
1088 | seccomp, | |
1089 | SCMP_ACT_ERRNO(EPERM), | |
1090 | SCMP_SYS(clone), | |
1091 | 1, | |
1092 | SCMP_A0(SCMP_CMP_MASKED_EQ, f, f)); | |
1093 | else | |
1094 | r = seccomp_rule_add_exact( | |
1095 | seccomp, | |
1096 | SCMP_ACT_ERRNO(EPERM), | |
1097 | SCMP_SYS(clone), | |
1098 | 1, | |
1099 | SCMP_A1(SCMP_CMP_MASKED_EQ, f, f)); | |
469830d1 LP |
1100 | if (r < 0) { |
1101 | log_debug_errno(r, "Failed to add clone() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1102 | break; | |
1103 | } | |
1104 | ||
1105 | if ((retain & NAMESPACE_FLAGS_ALL) != 0) { | |
1106 | r = seccomp_rule_add_exact( | |
1107 | seccomp, | |
1108 | SCMP_ACT_ERRNO(EPERM), | |
1109 | SCMP_SYS(setns), | |
1110 | 1, | |
1111 | SCMP_A1(SCMP_CMP_MASKED_EQ, f, f)); | |
1112 | if (r < 0) { | |
1113 | log_debug_errno(r, "Failed to add setns() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1114 | break; | |
1115 | } | |
1116 | } | |
1117 | } | |
1118 | if (r < 0) | |
1119 | continue; | |
1120 | ||
1121 | r = seccomp_load(seccomp); | |
1122 | if (IN_SET(r, -EPERM, -EACCES)) | |
1123 | return r; | |
1124 | if (r < 0) | |
1125 | log_debug_errno(r, "Failed to install namespace restriction rules for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1126 | } | |
1127 | ||
1128 | return 0; | |
1129 | } | |
1130 | ||
1131 | int seccomp_protect_sysctl(void) { | |
1132 | uint32_t arch; | |
1133 | int r; | |
1134 | ||
1135 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { | |
1136 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
1137 | ||
1138 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); | |
1139 | ||
2e64e8f4 ZJS |
1140 | if (IN_SET(arch, SCMP_ARCH_X32, SCMP_ARCH_AARCH64)) |
1141 | /* No _sysctl syscall */ | |
1142 | continue; | |
1143 | ||
469830d1 LP |
1144 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); |
1145 | if (r < 0) | |
1146 | return r; | |
1147 | ||
1148 | r = seccomp_rule_add_exact( | |
add00535 LP |
1149 | seccomp, |
1150 | SCMP_ACT_ERRNO(EPERM), | |
469830d1 | 1151 | SCMP_SYS(_sysctl), |
add00535 | 1152 | 0); |
469830d1 LP |
1153 | if (r < 0) { |
1154 | log_debug_errno(r, "Failed to add _sysctl() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1155 | continue; | |
1156 | } | |
1157 | ||
1158 | r = seccomp_load(seccomp); | |
1159 | if (IN_SET(r, -EPERM, -EACCES)) | |
1160 | return r; | |
1161 | if (r < 0) | |
1162 | log_debug_errno(r, "Failed to install sysctl protection rules for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1163 | } | |
1164 | ||
1165 | return 0; | |
1166 | } | |
1167 | ||
1168 | int seccomp_restrict_address_families(Set *address_families, bool whitelist) { | |
1169 | uint32_t arch; | |
1170 | int r; | |
1171 | ||
1172 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { | |
1173 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
9606bc4b | 1174 | bool supported; |
469830d1 LP |
1175 | Iterator i; |
1176 | ||
1177 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); | |
1178 | ||
9606bc4b LP |
1179 | switch (arch) { |
1180 | ||
1181 | case SCMP_ARCH_X86_64: | |
1182 | case SCMP_ARCH_X32: | |
1183 | case SCMP_ARCH_ARM: | |
1184 | case SCMP_ARCH_AARCH64: | |
0d9fca76 | 1185 | case SCMP_ARCH_PPC: |
da1921a5 ZJS |
1186 | case SCMP_ARCH_PPC64: |
1187 | case SCMP_ARCH_PPC64LE: | |
f5aeac14 JC |
1188 | case SCMP_ARCH_MIPSEL64N32: |
1189 | case SCMP_ARCH_MIPS64N32: | |
1190 | case SCMP_ARCH_MIPSEL64: | |
1191 | case SCMP_ARCH_MIPS64: | |
9606bc4b LP |
1192 | /* These we know we support (i.e. are the ones that do not use socketcall()) */ |
1193 | supported = true; | |
1194 | break; | |
1195 | ||
9606bc4b LP |
1196 | case SCMP_ARCH_S390: |
1197 | case SCMP_ARCH_S390X: | |
da1921a5 | 1198 | case SCMP_ARCH_X86: |
f5aeac14 JC |
1199 | case SCMP_ARCH_MIPSEL: |
1200 | case SCMP_ARCH_MIPS: | |
9606bc4b LP |
1201 | default: |
1202 | /* These we either know we don't support (i.e. are the ones that do use socketcall()), or we | |
1203 | * don't know */ | |
1204 | supported = false; | |
1205 | break; | |
1206 | } | |
1207 | ||
1208 | if (!supported) | |
1209 | continue; | |
1210 | ||
469830d1 LP |
1211 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); |
1212 | if (r < 0) | |
1213 | return r; | |
1214 | ||
1215 | if (whitelist) { | |
1216 | int af, first = 0, last = 0; | |
1217 | void *afp; | |
1218 | ||
1219 | /* If this is a whitelist, we first block the address families that are out of range and then | |
1220 | * everything that is not in the set. First, we find the lowest and highest address family in | |
1221 | * the set. */ | |
1222 | ||
1223 | SET_FOREACH(afp, address_families, i) { | |
1224 | af = PTR_TO_INT(afp); | |
1225 | ||
1226 | if (af <= 0 || af >= af_max()) | |
1227 | continue; | |
1228 | ||
1229 | if (first == 0 || af < first) | |
1230 | first = af; | |
1231 | ||
1232 | if (last == 0 || af > last) | |
1233 | last = af; | |
1234 | } | |
1235 | ||
1236 | assert((first == 0) == (last == 0)); | |
1237 | ||
1238 | if (first == 0) { | |
1239 | ||
1240 | /* No entries in the valid range, block everything */ | |
1241 | r = seccomp_rule_add_exact( | |
1242 | seccomp, | |
1243 | SCMP_ACT_ERRNO(EAFNOSUPPORT), | |
1244 | SCMP_SYS(socket), | |
1245 | 0); | |
1246 | if (r < 0) { | |
1247 | log_debug_errno(r, "Failed to add socket() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1248 | continue; | |
1249 | } | |
1250 | ||
1251 | } else { | |
1252 | ||
1253 | /* Block everything below the first entry */ | |
1254 | r = seccomp_rule_add_exact( | |
1255 | seccomp, | |
1256 | SCMP_ACT_ERRNO(EAFNOSUPPORT), | |
1257 | SCMP_SYS(socket), | |
1258 | 1, | |
1259 | SCMP_A0(SCMP_CMP_LT, first)); | |
1260 | if (r < 0) { | |
1261 | log_debug_errno(r, "Failed to add socket() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1262 | continue; | |
1263 | } | |
1264 | ||
1265 | /* Block everything above the last entry */ | |
1266 | r = seccomp_rule_add_exact( | |
1267 | seccomp, | |
1268 | SCMP_ACT_ERRNO(EAFNOSUPPORT), | |
1269 | SCMP_SYS(socket), | |
1270 | 1, | |
1271 | SCMP_A0(SCMP_CMP_GT, last)); | |
1272 | if (r < 0) { | |
1273 | log_debug_errno(r, "Failed to add socket() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1274 | continue; | |
1275 | } | |
1276 | ||
1277 | /* Block everything between the first and last entry */ | |
1278 | for (af = 1; af < af_max(); af++) { | |
1279 | ||
1280 | if (set_contains(address_families, INT_TO_PTR(af))) | |
1281 | continue; | |
1282 | ||
1283 | r = seccomp_rule_add_exact( | |
1284 | seccomp, | |
1285 | SCMP_ACT_ERRNO(EAFNOSUPPORT), | |
1286 | SCMP_SYS(socket), | |
1287 | 1, | |
1288 | SCMP_A0(SCMP_CMP_EQ, af)); | |
1289 | if (r < 0) | |
1290 | break; | |
1291 | } | |
469830d1 LP |
1292 | if (r < 0) { |
1293 | log_debug_errno(r, "Failed to add socket() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1294 | continue; | |
1295 | } | |
1296 | } | |
1297 | ||
1298 | } else { | |
1299 | void *af; | |
1300 | ||
1301 | /* If this is a blacklist, then generate one rule for | |
1302 | * each address family that are then combined in OR | |
1303 | * checks. */ | |
1304 | ||
1305 | SET_FOREACH(af, address_families, i) { | |
1306 | ||
1307 | r = seccomp_rule_add_exact( | |
1308 | seccomp, | |
1309 | SCMP_ACT_ERRNO(EAFNOSUPPORT), | |
1310 | SCMP_SYS(socket), | |
1311 | 1, | |
1312 | SCMP_A0(SCMP_CMP_EQ, PTR_TO_INT(af))); | |
1313 | if (r < 0) | |
1314 | break; | |
1315 | } | |
469830d1 LP |
1316 | if (r < 0) { |
1317 | log_debug_errno(r, "Failed to add socket() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1318 | continue; | |
1319 | } | |
1320 | } | |
1321 | ||
1322 | r = seccomp_load(seccomp); | |
1323 | if (IN_SET(r, -EPERM, -EACCES)) | |
1324 | return r; | |
1325 | if (r < 0) | |
1326 | log_debug_errno(r, "Failed to install socket family rules for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1327 | } | |
1328 | ||
1329 | return 0; | |
1330 | } | |
1331 | ||
1332 | int seccomp_restrict_realtime(void) { | |
1333 | static const int permitted_policies[] = { | |
1334 | SCHED_OTHER, | |
1335 | SCHED_BATCH, | |
1336 | SCHED_IDLE, | |
1337 | }; | |
1338 | ||
1339 | int r, max_policy = 0; | |
1340 | uint32_t arch; | |
1341 | unsigned i; | |
1342 | ||
1343 | /* Determine the highest policy constant we want to allow */ | |
1344 | for (i = 0; i < ELEMENTSOF(permitted_policies); i++) | |
1345 | if (permitted_policies[i] > max_policy) | |
1346 | max_policy = permitted_policies[i]; | |
1347 | ||
1348 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { | |
1349 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
1350 | int p; | |
1351 | ||
1352 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); | |
1353 | ||
1354 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); | |
1355 | if (r < 0) | |
1356 | return r; | |
1357 | ||
1358 | /* Go through all policies with lower values than that, and block them -- unless they appear in the | |
1359 | * whitelist. */ | |
1360 | for (p = 0; p < max_policy; p++) { | |
1361 | bool good = false; | |
1362 | ||
1363 | /* Check if this is in the whitelist. */ | |
1364 | for (i = 0; i < ELEMENTSOF(permitted_policies); i++) | |
1365 | if (permitted_policies[i] == p) { | |
1366 | good = true; | |
1367 | break; | |
1368 | } | |
1369 | ||
1370 | if (good) | |
1371 | continue; | |
1372 | ||
1373 | /* Deny this policy */ | |
1374 | r = seccomp_rule_add_exact( | |
1375 | seccomp, | |
1376 | SCMP_ACT_ERRNO(EPERM), | |
1377 | SCMP_SYS(sched_setscheduler), | |
1378 | 1, | |
1379 | SCMP_A1(SCMP_CMP_EQ, p)); | |
1380 | if (r < 0) { | |
1381 | log_debug_errno(r, "Failed to add scheduler rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1382 | continue; | |
1383 | } | |
1384 | } | |
1385 | ||
1386 | /* Blacklist all other policies, i.e. the ones with higher values. Note that all comparisons are | |
1387 | * unsigned here, hence no need no check for < 0 values. */ | |
1388 | r = seccomp_rule_add_exact( | |
add00535 LP |
1389 | seccomp, |
1390 | SCMP_ACT_ERRNO(EPERM), | |
469830d1 | 1391 | SCMP_SYS(sched_setscheduler), |
add00535 | 1392 | 1, |
469830d1 LP |
1393 | SCMP_A1(SCMP_CMP_GT, max_policy)); |
1394 | if (r < 0) { | |
1395 | log_debug_errno(r, "Failed to add scheduler rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1396 | continue; | |
1397 | } | |
add00535 | 1398 | |
469830d1 LP |
1399 | r = seccomp_load(seccomp); |
1400 | if (IN_SET(r, -EPERM, -EACCES)) | |
1401 | return r; | |
1402 | if (r < 0) | |
1403 | log_debug_errno(r, "Failed to install realtime protection rules for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1404 | } | |
1405 | ||
1406 | return 0; | |
1407 | } | |
1408 | ||
6dc66688 ZJS |
1409 | static int add_seccomp_syscall_filter(scmp_filter_ctx seccomp, |
1410 | uint32_t arch, | |
1411 | int nr, | |
1412 | unsigned int arg_cnt, | |
1413 | const struct scmp_arg_cmp arg) { | |
1414 | int r; | |
1415 | ||
1416 | r = seccomp_rule_add_exact(seccomp, SCMP_ACT_ERRNO(EPERM), nr, arg_cnt, arg); | |
1417 | if (r < 0) { | |
1418 | _cleanup_free_ char *n = NULL; | |
1419 | ||
1420 | n = seccomp_syscall_resolve_num_arch(arch, nr); | |
1421 | log_debug_errno(r, "Failed to add %s() rule for architecture %s, skipping: %m", | |
1422 | strna(n), | |
1423 | seccomp_arch_to_string(arch)); | |
1424 | } | |
1425 | ||
1426 | return r; | |
1427 | } | |
1428 | ||
2a8d6e63 | 1429 | /* For known architectures, check that syscalls are indeed defined or not. */ |
303d6b4c | 1430 | #if defined(__x86_64__) || defined(__arm__) || defined(__aarch64__) |
2a8d6e63 ZJS |
1431 | assert_cc(SCMP_SYS(shmget) > 0); |
1432 | assert_cc(SCMP_SYS(shmat) > 0); | |
1433 | assert_cc(SCMP_SYS(shmdt) > 0); | |
303d6b4c | 1434 | #elif defined(__i386__) || defined(__powerpc64__) |
2a8d6e63 ZJS |
1435 | assert_cc(SCMP_SYS(shmget) < 0); |
1436 | assert_cc(SCMP_SYS(shmat) < 0); | |
1437 | assert_cc(SCMP_SYS(shmdt) < 0); | |
1438 | #endif | |
6dc66688 | 1439 | |
469830d1 | 1440 | int seccomp_memory_deny_write_execute(void) { |
8a50cf69 | 1441 | |
469830d1 LP |
1442 | uint32_t arch; |
1443 | int r; | |
1444 | ||
1445 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { | |
1446 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
8a50cf69 | 1447 | int filter_syscall = 0, block_syscall = 0, shmat_syscall = 0; |
add00535 | 1448 | |
469830d1 LP |
1449 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); |
1450 | ||
8a50cf69 LP |
1451 | switch (arch) { |
1452 | ||
1453 | case SCMP_ARCH_X86: | |
1454 | filter_syscall = SCMP_SYS(mmap2); | |
1455 | block_syscall = SCMP_SYS(mmap); | |
2a8d6e63 ZJS |
1456 | break; |
1457 | ||
63d00dfb | 1458 | case SCMP_ARCH_PPC: |
2a8d6e63 ZJS |
1459 | case SCMP_ARCH_PPC64: |
1460 | case SCMP_ARCH_PPC64LE: | |
1461 | filter_syscall = SCMP_SYS(mmap); | |
1462 | ||
1463 | /* Note that shmat() isn't available, and the call is multiplexed through ipc(). | |
1464 | * We ignore that here, which means there's still a way to get writable/executable | |
1465 | * memory, if an IPC key is mapped like this. That's a pity, but no total loss. */ | |
8a50cf69 | 1466 | |
8a50cf69 LP |
1467 | break; |
1468 | ||
4278d1f5 ZJS |
1469 | case SCMP_ARCH_ARM: |
1470 | filter_syscall = SCMP_SYS(mmap2); /* arm has only mmap2 */ | |
1471 | shmat_syscall = SCMP_SYS(shmat); | |
1472 | break; | |
1473 | ||
8a50cf69 LP |
1474 | case SCMP_ARCH_X86_64: |
1475 | case SCMP_ARCH_X32: | |
79873bc8 | 1476 | case SCMP_ARCH_AARCH64: |
303d6b4c | 1477 | filter_syscall = SCMP_SYS(mmap); /* amd64, x32, and arm64 have only mmap */ |
8a50cf69 LP |
1478 | shmat_syscall = SCMP_SYS(shmat); |
1479 | break; | |
1480 | ||
1481 | /* Please add more definitions here, if you port systemd to other architectures! */ | |
1482 | ||
303d6b4c | 1483 | #if !defined(__i386__) && !defined(__x86_64__) && !defined(__powerpc__) && !defined(__powerpc64__) && !defined(__arm__) && !defined(__aarch64__) |
8a50cf69 LP |
1484 | #warning "Consider adding the right mmap() syscall definitions here!" |
1485 | #endif | |
1486 | } | |
1487 | ||
1488 | /* Can't filter mmap() on this arch, then skip it */ | |
1489 | if (filter_syscall == 0) | |
1490 | continue; | |
1491 | ||
469830d1 LP |
1492 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); |
1493 | if (r < 0) | |
1494 | return r; | |
1495 | ||
6dc66688 ZJS |
1496 | r = add_seccomp_syscall_filter(seccomp, arch, filter_syscall, |
1497 | 1, | |
1498 | SCMP_A2(SCMP_CMP_MASKED_EQ, PROT_EXEC|PROT_WRITE, PROT_EXEC|PROT_WRITE)); | |
1499 | if (r < 0) | |
1500 | continue; | |
8a50cf69 LP |
1501 | |
1502 | if (block_syscall != 0) { | |
6dc66688 ZJS |
1503 | r = add_seccomp_syscall_filter(seccomp, arch, block_syscall, 0, (const struct scmp_arg_cmp){} ); |
1504 | if (r < 0) | |
8a50cf69 | 1505 | continue; |
add00535 | 1506 | } |
a3be2849 | 1507 | |
6dc66688 ZJS |
1508 | r = add_seccomp_syscall_filter(seccomp, arch, SCMP_SYS(mprotect), |
1509 | 1, | |
b835eeb4 ZJS |
1510 | SCMP_A2(SCMP_CMP_MASKED_EQ, PROT_EXEC, PROT_EXEC)); |
1511 | if (r < 0) | |
1512 | continue; | |
1513 | ||
91691f1d | 1514 | #ifdef __NR_pkey_mprotect |
b835eeb4 ZJS |
1515 | r = add_seccomp_syscall_filter(seccomp, arch, SCMP_SYS(pkey_mprotect), |
1516 | 1, | |
6dc66688 ZJS |
1517 | SCMP_A2(SCMP_CMP_MASKED_EQ, PROT_EXEC, PROT_EXEC)); |
1518 | if (r < 0) | |
469830d1 | 1519 | continue; |
91691f1d | 1520 | #endif |
add00535 | 1521 | |
8a50cf69 | 1522 | if (shmat_syscall != 0) { |
6dc66688 ZJS |
1523 | r = add_seccomp_syscall_filter(seccomp, arch, SCMP_SYS(shmat), |
1524 | 1, | |
1525 | SCMP_A2(SCMP_CMP_MASKED_EQ, SHM_EXEC, SHM_EXEC)); | |
1526 | if (r < 0) | |
8a50cf69 | 1527 | continue; |
469830d1 LP |
1528 | } |
1529 | ||
1530 | r = seccomp_load(seccomp); | |
1531 | if (IN_SET(r, -EPERM, -EACCES)) | |
1532 | return r; | |
add00535 | 1533 | if (r < 0) |
469830d1 LP |
1534 | log_debug_errno(r, "Failed to install MemoryDenyWriteExecute= rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); |
1535 | } | |
add00535 | 1536 | |
469830d1 LP |
1537 | return 0; |
1538 | } | |
1539 | ||
1540 | int seccomp_restrict_archs(Set *archs) { | |
1541 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
1542 | Iterator i; | |
1543 | void *id; | |
1544 | int r; | |
1545 | ||
1546 | /* This installs a filter with no rules, but that restricts the system call architectures to the specified | |
2428aaf8 AJ |
1547 | * list. |
1548 | * | |
1549 | * There are some qualifications. However the most important use is to stop processes from bypassing | |
1550 | * system call restrictions, in case they used a broader (multiplexing) syscall which is only available | |
1551 | * in a non-native architecture. There are no holes in this use case, at least so far. */ | |
469830d1 | 1552 | |
2428aaf8 AJ |
1553 | /* Note libseccomp includes our "native" (current) architecture in the filter by default. |
1554 | * We do not remove it. For example, our callers expect to be able to call execve() afterwards | |
1555 | * to run a program with the restrictions applied. */ | |
469830d1 LP |
1556 | seccomp = seccomp_init(SCMP_ACT_ALLOW); |
1557 | if (!seccomp) | |
1558 | return -ENOMEM; | |
1559 | ||
1560 | SET_FOREACH(id, archs, i) { | |
1561 | r = seccomp_arch_add(seccomp, PTR_TO_UINT32(id) - 1); | |
2428aaf8 AJ |
1562 | if (r < 0 && r != -EEXIST) |
1563 | return r; | |
1564 | } | |
1565 | ||
1566 | /* The vdso for x32 assumes that x86-64 syscalls are available. Let's allow them, since x32 | |
1567 | * x32 syscalls should basically match x86-64 for everything except the pointer type. | |
1568 | * The important thing is that you can block the old 32-bit x86 syscalls. | |
1569 | * https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=850047 */ | |
1570 | ||
1571 | if (seccomp_arch_native() == SCMP_ARCH_X32 || | |
1572 | set_contains(archs, UINT32_TO_PTR(SCMP_ARCH_X32 + 1))) { | |
1573 | ||
1574 | r = seccomp_arch_add(seccomp, SCMP_ARCH_X86_64); | |
1575 | if (r < 0 && r != -EEXIST) | |
469830d1 | 1576 | return r; |
add00535 LP |
1577 | } |
1578 | ||
469830d1 LP |
1579 | r = seccomp_attr_set(seccomp, SCMP_FLTATR_CTL_NNP, 0); |
1580 | if (r < 0) | |
1581 | return r; | |
add00535 | 1582 | |
1c6af69b LP |
1583 | r = seccomp_load(seccomp); |
1584 | if (IN_SET(r, -EPERM, -EACCES)) | |
1585 | return r; | |
1586 | if (r < 0) | |
1587 | log_debug_errno(r, "Failed to restrict system call architectures, skipping: %m"); | |
1588 | ||
1589 | return 0; | |
a3be2849 | 1590 | } |
b16bd535 YW |
1591 | |
1592 | int parse_syscall_archs(char **l, Set **archs) { | |
1593 | _cleanup_set_free_ Set *_archs; | |
1594 | char **s; | |
1595 | int r; | |
1596 | ||
1597 | assert(l); | |
1598 | assert(archs); | |
1599 | ||
1600 | r = set_ensure_allocated(&_archs, NULL); | |
1601 | if (r < 0) | |
1602 | return r; | |
1603 | ||
1604 | STRV_FOREACH(s, l) { | |
1605 | uint32_t a; | |
1606 | ||
1607 | r = seccomp_arch_from_string(*s, &a); | |
1608 | if (r < 0) | |
1609 | return -EINVAL; | |
1610 | ||
1611 | r = set_put(_archs, UINT32_TO_PTR(a + 1)); | |
1612 | if (r < 0) | |
1613 | return -ENOMEM; | |
1614 | } | |
1615 | ||
1cc6c93a | 1616 | *archs = TAKE_PTR(_archs); |
b16bd535 YW |
1617 | |
1618 | return 0; | |
1619 | } | |
165a31c0 | 1620 | |
8cfa775f | 1621 | int seccomp_filter_set_add(Hashmap *filter, bool add, const SyscallFilterSet *set) { |
165a31c0 LP |
1622 | const char *i; |
1623 | int r; | |
1624 | ||
1625 | assert(set); | |
1626 | ||
1627 | NULSTR_FOREACH(i, set->value) { | |
1628 | ||
1629 | if (i[0] == '@') { | |
1630 | const SyscallFilterSet *more; | |
1631 | ||
1632 | more = syscall_filter_set_find(i); | |
1633 | if (!more) | |
1634 | return -ENXIO; | |
1635 | ||
165a31c0 LP |
1636 | r = seccomp_filter_set_add(filter, add, more); |
1637 | if (r < 0) | |
1638 | return r; | |
1639 | } else { | |
1640 | int id; | |
1641 | ||
1642 | id = seccomp_syscall_resolve_name(i); | |
ff217dc3 LP |
1643 | if (id == __NR_SCMP_ERROR) { |
1644 | log_debug("Couldn't resolve system call, ignoring: %s", i); | |
1645 | continue; | |
1646 | } | |
165a31c0 LP |
1647 | |
1648 | if (add) { | |
8cfa775f | 1649 | r = hashmap_put(filter, INT_TO_PTR(id + 1), INT_TO_PTR(-1)); |
165a31c0 LP |
1650 | if (r < 0) |
1651 | return r; | |
1652 | } else | |
8cfa775f | 1653 | (void) hashmap_remove(filter, INT_TO_PTR(id + 1)); |
165a31c0 LP |
1654 | } |
1655 | } | |
1656 | ||
1657 | return 0; | |
1658 | } | |
78e864e5 TM |
1659 | |
1660 | int seccomp_lock_personality(unsigned long personality) { | |
72eafe71 | 1661 | uint32_t arch; |
78e864e5 TM |
1662 | int r; |
1663 | ||
72eafe71 LP |
1664 | if (personality >= PERSONALITY_INVALID) |
1665 | return -EINVAL; | |
78e864e5 | 1666 | |
72eafe71 LP |
1667 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { |
1668 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
78e864e5 | 1669 | |
72eafe71 LP |
1670 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); |
1671 | if (r < 0) | |
1672 | return r; | |
1673 | ||
1674 | r = seccomp_rule_add_exact( | |
1675 | seccomp, | |
1676 | SCMP_ACT_ERRNO(EPERM), | |
1677 | SCMP_SYS(personality), | |
1678 | 1, | |
1679 | SCMP_A0(SCMP_CMP_NE, personality)); | |
448ac526 LP |
1680 | if (r < 0) { |
1681 | log_debug_errno(r, "Failed to add scheduler rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1682 | continue; | |
1683 | } | |
72eafe71 LP |
1684 | |
1685 | r = seccomp_load(seccomp); | |
1686 | if (IN_SET(r, -EPERM, -EACCES)) | |
1687 | return r; | |
1688 | if (r < 0) | |
1689 | log_debug_errno(r, "Failed to enable personality lock for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1690 | } | |
1691 | ||
1692 | return 0; | |
78e864e5 | 1693 | } |