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53e1b683 | 1 | /* SPDX-License-Identifier: LGPL-2.1+ */ |
57183d11 | 2 | |
a8fbdf54 | 3 | #include <errno.h> |
3c27973b | 4 | #include <fcntl.h> |
469830d1 | 5 | #include <linux/seccomp.h> |
57183d11 | 6 | #include <seccomp.h> |
a8fbdf54 | 7 | #include <stddef.h> |
469830d1 | 8 | #include <sys/mman.h> |
d347d902 | 9 | #include <sys/prctl.h> |
469830d1 | 10 | #include <sys/shm.h> |
3c27973b | 11 | #include <sys/stat.h> |
57183d11 | 12 | |
469830d1 | 13 | #include "af-list.h" |
add00535 | 14 | #include "alloc-util.h" |
d8b4d14d | 15 | #include "errno-list.h" |
a8fbdf54 | 16 | #include "macro.h" |
add00535 | 17 | #include "nsflags.h" |
d8b4d14d | 18 | #include "nulstr-util.h" |
78e864e5 | 19 | #include "process-util.h" |
cf0fbc49 | 20 | #include "seccomp-util.h" |
b16bd535 | 21 | #include "set.h" |
07630cea | 22 | #include "string-util.h" |
b16bd535 | 23 | #include "strv.h" |
469830d1 LP |
24 | |
25 | const uint32_t seccomp_local_archs[] = { | |
26 | ||
f2d9751c LP |
27 | /* 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 */ |
28 | ||
29 | #if defined(__x86_64__) && defined(__ILP32__) | |
469830d1 LP |
30 | SCMP_ARCH_X86, |
31 | SCMP_ARCH_X86_64, | |
f2d9751c LP |
32 | SCMP_ARCH_X32, /* native */ |
33 | #elif defined(__x86_64__) && !defined(__ILP32__) | |
34 | SCMP_ARCH_X86, | |
469830d1 | 35 | SCMP_ARCH_X32, |
f2d9751c LP |
36 | SCMP_ARCH_X86_64, /* native */ |
37 | #elif defined(__i386__) | |
38 | SCMP_ARCH_X86, | |
39 | #elif defined(__aarch64__) | |
469830d1 | 40 | SCMP_ARCH_ARM, |
f2d9751c LP |
41 | SCMP_ARCH_AARCH64, /* native */ |
42 | #elif defined(__arm__) | |
43 | SCMP_ARCH_ARM, | |
44 | #elif defined(__mips__) && __BYTE_ORDER == __BIG_ENDIAN && _MIPS_SIM == _MIPS_SIM_ABI32 | |
45 | SCMP_ARCH_MIPSEL, | |
46 | SCMP_ARCH_MIPS, /* native */ | |
47 | #elif defined(__mips__) && __BYTE_ORDER == __LITTLE_ENDIAN && _MIPS_SIM == _MIPS_SIM_ABI32 | |
469830d1 | 48 | SCMP_ARCH_MIPS, |
f2d9751c LP |
49 | SCMP_ARCH_MIPSEL, /* native */ |
50 | #elif defined(__mips__) && __BYTE_ORDER == __BIG_ENDIAN && _MIPS_SIM == _MIPS_SIM_ABI64 | |
51 | SCMP_ARCH_MIPSEL, | |
52 | SCMP_ARCH_MIPS, | |
53 | SCMP_ARCH_MIPSEL64N32, | |
469830d1 | 54 | SCMP_ARCH_MIPS64N32, |
f2d9751c LP |
55 | SCMP_ARCH_MIPSEL64, |
56 | SCMP_ARCH_MIPS64, /* native */ | |
57 | #elif defined(__mips__) && __BYTE_ORDER == __LITTLE_ENDIAN && _MIPS_SIM == _MIPS_SIM_ABI64 | |
58 | SCMP_ARCH_MIPS, | |
469830d1 | 59 | SCMP_ARCH_MIPSEL, |
f2d9751c LP |
60 | SCMP_ARCH_MIPS64N32, |
61 | SCMP_ARCH_MIPSEL64N32, | |
62 | SCMP_ARCH_MIPS64, | |
63 | SCMP_ARCH_MIPSEL64, /* native */ | |
64 | #elif defined(__mips__) && __BYTE_ORDER == __BIG_ENDIAN && _MIPS_SIM == _MIPS_SIM_NABI32 | |
65 | SCMP_ARCH_MIPSEL, | |
66 | SCMP_ARCH_MIPS, | |
469830d1 | 67 | SCMP_ARCH_MIPSEL64, |
f2d9751c | 68 | SCMP_ARCH_MIPS64, |
469830d1 | 69 | SCMP_ARCH_MIPSEL64N32, |
f2d9751c LP |
70 | SCMP_ARCH_MIPS64N32, /* native */ |
71 | #elif defined(__mips__) && __BYTE_ORDER == __LITTLE_ENDIAN && _MIPS_SIM == _MIPS_SIM_NABI32 | |
72 | SCMP_ARCH_MIPS, | |
73 | SCMP_ARCH_MIPSEL, | |
74 | SCMP_ARCH_MIPS64, | |
75 | SCMP_ARCH_MIPSEL64, | |
76 | SCMP_ARCH_MIPS64N32, | |
77 | SCMP_ARCH_MIPSEL64N32, /* native */ | |
78 | #elif defined(__powerpc64__) && __BYTE_ORDER == __BIG_ENDIAN | |
469830d1 | 79 | SCMP_ARCH_PPC, |
469830d1 | 80 | SCMP_ARCH_PPC64LE, |
f2d9751c LP |
81 | SCMP_ARCH_PPC64, /* native */ |
82 | #elif defined(__powerpc64__) && __BYTE_ORDER == __LITTLE_ENDIAN | |
83 | SCMP_ARCH_PPC, | |
84 | SCMP_ARCH_PPC64, | |
85 | SCMP_ARCH_PPC64LE, /* native */ | |
86 | #elif defined(__powerpc__) | |
87 | SCMP_ARCH_PPC, | |
88 | #elif defined(__s390x__) | |
89 | SCMP_ARCH_S390, | |
90 | SCMP_ARCH_S390X, /* native */ | |
91 | #elif defined(__s390__) | |
469830d1 | 92 | SCMP_ARCH_S390, |
469830d1 LP |
93 | #endif |
94 | (uint32_t) -1 | |
95 | }; | |
57183d11 LP |
96 | |
97 | const char* seccomp_arch_to_string(uint32_t c) { | |
aa34055f ZJS |
98 | /* Maintain order used in <seccomp.h>. |
99 | * | |
100 | * Names used here should be the same as those used for ConditionArchitecture=, | |
101 | * except for "subarchitectures" like x32. */ | |
57183d11 | 102 | |
aa34055f ZJS |
103 | switch(c) { |
104 | case SCMP_ARCH_NATIVE: | |
57183d11 | 105 | return "native"; |
aa34055f | 106 | case SCMP_ARCH_X86: |
57183d11 | 107 | return "x86"; |
aa34055f | 108 | case SCMP_ARCH_X86_64: |
57183d11 | 109 | return "x86-64"; |
aa34055f | 110 | case SCMP_ARCH_X32: |
57183d11 | 111 | return "x32"; |
aa34055f | 112 | case SCMP_ARCH_ARM: |
57183d11 | 113 | return "arm"; |
aa34055f ZJS |
114 | case SCMP_ARCH_AARCH64: |
115 | return "arm64"; | |
116 | case SCMP_ARCH_MIPS: | |
117 | return "mips"; | |
118 | case SCMP_ARCH_MIPS64: | |
119 | return "mips64"; | |
120 | case SCMP_ARCH_MIPS64N32: | |
121 | return "mips64-n32"; | |
122 | case SCMP_ARCH_MIPSEL: | |
123 | return "mips-le"; | |
124 | case SCMP_ARCH_MIPSEL64: | |
125 | return "mips64-le"; | |
126 | case SCMP_ARCH_MIPSEL64N32: | |
127 | return "mips64-le-n32"; | |
128 | case SCMP_ARCH_PPC: | |
129 | return "ppc"; | |
130 | case SCMP_ARCH_PPC64: | |
131 | return "ppc64"; | |
132 | case SCMP_ARCH_PPC64LE: | |
133 | return "ppc64-le"; | |
134 | case SCMP_ARCH_S390: | |
6abfd303 | 135 | return "s390"; |
aa34055f | 136 | case SCMP_ARCH_S390X: |
6abfd303 | 137 | return "s390x"; |
aa34055f ZJS |
138 | default: |
139 | return NULL; | |
140 | } | |
57183d11 LP |
141 | } |
142 | ||
143 | int seccomp_arch_from_string(const char *n, uint32_t *ret) { | |
144 | if (!n) | |
145 | return -EINVAL; | |
146 | ||
147 | assert(ret); | |
148 | ||
149 | if (streq(n, "native")) | |
150 | *ret = SCMP_ARCH_NATIVE; | |
151 | else if (streq(n, "x86")) | |
152 | *ret = SCMP_ARCH_X86; | |
153 | else if (streq(n, "x86-64")) | |
154 | *ret = SCMP_ARCH_X86_64; | |
155 | else if (streq(n, "x32")) | |
156 | *ret = SCMP_ARCH_X32; | |
157 | else if (streq(n, "arm")) | |
158 | *ret = SCMP_ARCH_ARM; | |
aa34055f ZJS |
159 | else if (streq(n, "arm64")) |
160 | *ret = SCMP_ARCH_AARCH64; | |
161 | else if (streq(n, "mips")) | |
162 | *ret = SCMP_ARCH_MIPS; | |
163 | else if (streq(n, "mips64")) | |
164 | *ret = SCMP_ARCH_MIPS64; | |
165 | else if (streq(n, "mips64-n32")) | |
166 | *ret = SCMP_ARCH_MIPS64N32; | |
167 | else if (streq(n, "mips-le")) | |
168 | *ret = SCMP_ARCH_MIPSEL; | |
169 | else if (streq(n, "mips64-le")) | |
170 | *ret = SCMP_ARCH_MIPSEL64; | |
171 | else if (streq(n, "mips64-le-n32")) | |
172 | *ret = SCMP_ARCH_MIPSEL64N32; | |
173 | else if (streq(n, "ppc")) | |
174 | *ret = SCMP_ARCH_PPC; | |
175 | else if (streq(n, "ppc64")) | |
176 | *ret = SCMP_ARCH_PPC64; | |
177 | else if (streq(n, "ppc64-le")) | |
178 | *ret = SCMP_ARCH_PPC64LE; | |
6abfd303 HB |
179 | else if (streq(n, "s390")) |
180 | *ret = SCMP_ARCH_S390; | |
181 | else if (streq(n, "s390x")) | |
182 | *ret = SCMP_ARCH_S390X; | |
57183d11 LP |
183 | else |
184 | return -EINVAL; | |
185 | ||
186 | return 0; | |
187 | } | |
e9642be2 | 188 | |
469830d1 | 189 | int seccomp_init_for_arch(scmp_filter_ctx *ret, uint32_t arch, uint32_t default_action) { |
8d7b0c8f LP |
190 | scmp_filter_ctx seccomp; |
191 | int r; | |
192 | ||
469830d1 LP |
193 | /* Much like seccomp_init(), but initializes the filter for one specific architecture only, without affecting |
194 | * any others. Also, turns off the NNP fiddling. */ | |
8d7b0c8f LP |
195 | |
196 | seccomp = seccomp_init(default_action); | |
197 | if (!seccomp) | |
198 | return -ENOMEM; | |
199 | ||
469830d1 LP |
200 | if (arch != SCMP_ARCH_NATIVE && |
201 | arch != seccomp_arch_native()) { | |
202 | ||
1b52793d | 203 | r = seccomp_arch_remove(seccomp, seccomp_arch_native()); |
469830d1 LP |
204 | if (r < 0) |
205 | goto finish; | |
206 | ||
1b52793d | 207 | r = seccomp_arch_add(seccomp, arch); |
469830d1 LP |
208 | if (r < 0) |
209 | goto finish; | |
210 | ||
211 | assert(seccomp_arch_exist(seccomp, arch) >= 0); | |
212 | assert(seccomp_arch_exist(seccomp, SCMP_ARCH_NATIVE) == -EEXIST); | |
213 | assert(seccomp_arch_exist(seccomp, seccomp_arch_native()) == -EEXIST); | |
214 | } else { | |
215 | assert(seccomp_arch_exist(seccomp, SCMP_ARCH_NATIVE) >= 0); | |
216 | assert(seccomp_arch_exist(seccomp, seccomp_arch_native()) >= 0); | |
217 | } | |
218 | ||
219 | r = seccomp_attr_set(seccomp, SCMP_FLTATR_ACT_BADARCH, SCMP_ACT_ALLOW); | |
8d7b0c8f LP |
220 | if (r < 0) |
221 | goto finish; | |
222 | ||
223 | r = seccomp_attr_set(seccomp, SCMP_FLTATR_CTL_NNP, 0); | |
224 | if (r < 0) | |
225 | goto finish; | |
226 | ||
227 | *ret = seccomp; | |
228 | return 0; | |
229 | ||
230 | finish: | |
231 | seccomp_release(seccomp); | |
232 | return r; | |
233 | } | |
234 | ||
d347d902 | 235 | static bool is_basic_seccomp_available(void) { |
4d5bd50a | 236 | return prctl(PR_GET_SECCOMP, 0, 0, 0, 0) >= 0; |
d347d902 FS |
237 | } |
238 | ||
239 | static bool is_seccomp_filter_available(void) { | |
4d5bd50a LP |
240 | return prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, NULL, 0, 0) < 0 && |
241 | errno == EFAULT; | |
d347d902 FS |
242 | } |
243 | ||
83f12b27 | 244 | bool is_seccomp_available(void) { |
83f12b27 | 245 | static int cached_enabled = -1; |
4d5bd50a | 246 | |
83f12b27 | 247 | if (cached_enabled < 0) |
4d5bd50a LP |
248 | cached_enabled = |
249 | is_basic_seccomp_available() && | |
250 | is_seccomp_filter_available(); | |
251 | ||
83f12b27 FS |
252 | return cached_enabled; |
253 | } | |
254 | ||
8130926d | 255 | const SyscallFilterSet syscall_filter_sets[_SYSCALL_FILTER_SET_MAX] = { |
40eb6a80 | 256 | [SYSCALL_FILTER_SET_DEFAULT] = { |
40eb6a80 | 257 | .name = "@default", |
d5efc18b | 258 | .help = "System calls that are always permitted", |
40eb6a80 ZJS |
259 | .value = |
260 | "clock_getres\0" | |
261 | "clock_gettime\0" | |
262 | "clock_nanosleep\0" | |
263 | "execve\0" | |
264 | "exit\0" | |
265 | "exit_group\0" | |
e41b0f42 LP |
266 | "futex\0" |
267 | "get_robust_list\0" | |
268 | "get_thread_area\0" | |
09d3020b DH |
269 | "getegid\0" |
270 | "getegid32\0" | |
271 | "geteuid\0" | |
272 | "geteuid32\0" | |
273 | "getgid\0" | |
274 | "getgid32\0" | |
275 | "getgroups\0" | |
276 | "getgroups32\0" | |
277 | "getpgid\0" | |
278 | "getpgrp\0" | |
279 | "getpid\0" | |
280 | "getppid\0" | |
281 | "getresgid\0" | |
282 | "getresgid32\0" | |
283 | "getresuid\0" | |
284 | "getresuid32\0" | |
40eb6a80 | 285 | "getrlimit\0" /* make sure processes can query stack size and such */ |
09d3020b DH |
286 | "getsid\0" |
287 | "gettid\0" | |
40eb6a80 | 288 | "gettimeofday\0" |
09d3020b DH |
289 | "getuid\0" |
290 | "getuid32\0" | |
e41b0f42 | 291 | "membarrier\0" |
40eb6a80 ZJS |
292 | "nanosleep\0" |
293 | "pause\0" | |
4c3a9176 | 294 | "prlimit64\0" |
e41b0f42 | 295 | "restart_syscall\0" |
6fee3be0 | 296 | "rseq\0" |
40eb6a80 | 297 | "rt_sigreturn\0" |
8f44de08 | 298 | "sched_yield\0" |
e41b0f42 LP |
299 | "set_robust_list\0" |
300 | "set_thread_area\0" | |
301 | "set_tid_address\0" | |
ce5faeac | 302 | "set_tls\0" |
40eb6a80 ZJS |
303 | "sigreturn\0" |
304 | "time\0" | |
4c3a9176 | 305 | "ugetrlimit\0" |
40eb6a80 | 306 | }, |
44898c53 LP |
307 | [SYSCALL_FILTER_SET_AIO] = { |
308 | .name = "@aio", | |
309 | .help = "Asynchronous IO", | |
310 | .value = | |
311 | "io_cancel\0" | |
312 | "io_destroy\0" | |
313 | "io_getevents\0" | |
a05cfe23 | 314 | "io_pgetevents\0" |
44898c53 LP |
315 | "io_setup\0" |
316 | "io_submit\0" | |
317 | }, | |
133ddbbe | 318 | [SYSCALL_FILTER_SET_BASIC_IO] = { |
133ddbbe | 319 | .name = "@basic-io", |
d5efc18b | 320 | .help = "Basic IO", |
133ddbbe | 321 | .value = |
648a0ed0 | 322 | "_llseek\0" |
133ddbbe | 323 | "close\0" |
648a0ed0 | 324 | "dup\0" |
133ddbbe LP |
325 | "dup2\0" |
326 | "dup3\0" | |
133ddbbe LP |
327 | "lseek\0" |
328 | "pread64\0" | |
329 | "preadv\0" | |
44898c53 | 330 | "preadv2\0" |
133ddbbe LP |
331 | "pwrite64\0" |
332 | "pwritev\0" | |
44898c53 | 333 | "pwritev2\0" |
133ddbbe LP |
334 | "read\0" |
335 | "readv\0" | |
336 | "write\0" | |
337 | "writev\0" | |
338 | }, | |
44898c53 LP |
339 | [SYSCALL_FILTER_SET_CHOWN] = { |
340 | .name = "@chown", | |
341 | .help = "Change ownership of files and directories", | |
342 | .value = | |
343 | "chown\0" | |
344 | "chown32\0" | |
345 | "fchown\0" | |
346 | "fchown32\0" | |
347 | "fchownat\0" | |
348 | "lchown\0" | |
349 | "lchown32\0" | |
350 | }, | |
8130926d | 351 | [SYSCALL_FILTER_SET_CLOCK] = { |
8130926d | 352 | .name = "@clock", |
d5efc18b | 353 | .help = "Change the system time", |
201c1cc2 TM |
354 | .value = |
355 | "adjtimex\0" | |
1f9ac68b LP |
356 | "clock_adjtime\0" |
357 | "clock_settime\0" | |
201c1cc2 | 358 | "settimeofday\0" |
1f9ac68b | 359 | "stime\0" |
8130926d LP |
360 | }, |
361 | [SYSCALL_FILTER_SET_CPU_EMULATION] = { | |
8130926d | 362 | .name = "@cpu-emulation", |
d5efc18b | 363 | .help = "System calls for CPU emulation functionality", |
1f9ac68b LP |
364 | .value = |
365 | "modify_ldt\0" | |
366 | "subpage_prot\0" | |
367 | "switch_endian\0" | |
368 | "vm86\0" | |
369 | "vm86old\0" | |
8130926d LP |
370 | }, |
371 | [SYSCALL_FILTER_SET_DEBUG] = { | |
8130926d | 372 | .name = "@debug", |
d5efc18b | 373 | .help = "Debugging, performance monitoring and tracing functionality", |
1f9ac68b LP |
374 | .value = |
375 | "lookup_dcookie\0" | |
376 | "perf_event_open\0" | |
1f9ac68b LP |
377 | "ptrace\0" |
378 | "rtas\0" | |
8130926d | 379 | #ifdef __NR_s390_runtime_instr |
1f9ac68b | 380 | "s390_runtime_instr\0" |
8130926d | 381 | #endif |
1f9ac68b | 382 | "sys_debug_setcontext\0" |
8130926d | 383 | }, |
1a1b13c9 LP |
384 | [SYSCALL_FILTER_SET_FILE_SYSTEM] = { |
385 | .name = "@file-system", | |
386 | .help = "File system operations", | |
387 | .value = | |
388 | "access\0" | |
389 | "chdir\0" | |
390 | "chmod\0" | |
391 | "close\0" | |
392 | "creat\0" | |
393 | "faccessat\0" | |
394 | "fallocate\0" | |
395 | "fchdir\0" | |
396 | "fchmod\0" | |
397 | "fchmodat\0" | |
1a1b13c9 | 398 | "fcntl\0" |
ceaa6aa7 | 399 | "fcntl64\0" |
1a1b13c9 LP |
400 | "fgetxattr\0" |
401 | "flistxattr\0" | |
ceaa6aa7 | 402 | "fremovexattr\0" |
1a1b13c9 | 403 | "fsetxattr\0" |
1a1b13c9 | 404 | "fstat\0" |
ceaa6aa7 | 405 | "fstat64\0" |
1a1b13c9 | 406 | "fstatat64\0" |
1a1b13c9 | 407 | "fstatfs\0" |
ceaa6aa7 | 408 | "fstatfs64\0" |
1a1b13c9 | 409 | "ftruncate\0" |
ceaa6aa7 | 410 | "ftruncate64\0" |
1a1b13c9 LP |
411 | "futimesat\0" |
412 | "getcwd\0" | |
1a1b13c9 | 413 | "getdents\0" |
ceaa6aa7 | 414 | "getdents64\0" |
1a1b13c9 LP |
415 | "getxattr\0" |
416 | "inotify_add_watch\0" | |
ceaa6aa7 | 417 | "inotify_init\0" |
1a1b13c9 LP |
418 | "inotify_init1\0" |
419 | "inotify_rm_watch\0" | |
420 | "lgetxattr\0" | |
421 | "link\0" | |
422 | "linkat\0" | |
423 | "listxattr\0" | |
424 | "llistxattr\0" | |
425 | "lremovexattr\0" | |
426 | "lsetxattr\0" | |
1a1b13c9 | 427 | "lstat\0" |
ceaa6aa7 | 428 | "lstat64\0" |
1a1b13c9 LP |
429 | "mkdir\0" |
430 | "mkdirat\0" | |
431 | "mknod\0" | |
432 | "mknodat\0" | |
1a1b13c9 | 433 | "mmap\0" |
ceaa6aa7 | 434 | "mmap2\0" |
7961116e | 435 | "munmap\0" |
1a1b13c9 | 436 | "newfstatat\0" |
ceaa6aa7 LP |
437 | "oldfstat\0" |
438 | "oldlstat\0" | |
439 | "oldstat\0" | |
1a1b13c9 LP |
440 | "open\0" |
441 | "openat\0" | |
442 | "readlink\0" | |
443 | "readlinkat\0" | |
444 | "removexattr\0" | |
445 | "rename\0" | |
1a1b13c9 | 446 | "renameat\0" |
ceaa6aa7 | 447 | "renameat2\0" |
1a1b13c9 LP |
448 | "rmdir\0" |
449 | "setxattr\0" | |
1a1b13c9 | 450 | "stat\0" |
ceaa6aa7 | 451 | "stat64\0" |
1a1b13c9 | 452 | "statfs\0" |
ceaa6aa7 | 453 | "statfs64\0" |
8e6a7a8b | 454 | #ifdef __NR_statx |
a4135a74 | 455 | "statx\0" |
ceaa6aa7 | 456 | #endif |
1a1b13c9 LP |
457 | "symlink\0" |
458 | "symlinkat\0" | |
1a1b13c9 | 459 | "truncate\0" |
ceaa6aa7 | 460 | "truncate64\0" |
1a1b13c9 LP |
461 | "unlink\0" |
462 | "unlinkat\0" | |
ceaa6aa7 | 463 | "utime\0" |
1a1b13c9 LP |
464 | "utimensat\0" |
465 | "utimes\0" | |
466 | }, | |
8130926d | 467 | [SYSCALL_FILTER_SET_IO_EVENT] = { |
8130926d | 468 | .name = "@io-event", |
d5efc18b | 469 | .help = "Event loop system calls", |
201c1cc2 TM |
470 | .value = |
471 | "_newselect\0" | |
201c1cc2 | 472 | "epoll_create\0" |
215728ff | 473 | "epoll_create1\0" |
201c1cc2 TM |
474 | "epoll_ctl\0" |
475 | "epoll_ctl_old\0" | |
476 | "epoll_pwait\0" | |
477 | "epoll_wait\0" | |
478 | "epoll_wait_old\0" | |
201c1cc2 | 479 | "eventfd\0" |
215728ff | 480 | "eventfd2\0" |
201c1cc2 TM |
481 | "poll\0" |
482 | "ppoll\0" | |
483 | "pselect6\0" | |
484 | "select\0" | |
8130926d LP |
485 | }, |
486 | [SYSCALL_FILTER_SET_IPC] = { | |
8130926d | 487 | .name = "@ipc", |
d5efc18b ZJS |
488 | .help = "SysV IPC, POSIX Message Queues or other IPC", |
489 | .value = | |
490 | "ipc\0" | |
cd5bfd7e | 491 | "memfd_create\0" |
201c1cc2 TM |
492 | "mq_getsetattr\0" |
493 | "mq_notify\0" | |
494 | "mq_open\0" | |
495 | "mq_timedreceive\0" | |
496 | "mq_timedsend\0" | |
497 | "mq_unlink\0" | |
498 | "msgctl\0" | |
499 | "msgget\0" | |
500 | "msgrcv\0" | |
501 | "msgsnd\0" | |
cd5bfd7e | 502 | "pipe\0" |
215728ff | 503 | "pipe2\0" |
201c1cc2 TM |
504 | "process_vm_readv\0" |
505 | "process_vm_writev\0" | |
506 | "semctl\0" | |
507 | "semget\0" | |
508 | "semop\0" | |
509 | "semtimedop\0" | |
510 | "shmat\0" | |
511 | "shmctl\0" | |
512 | "shmdt\0" | |
513 | "shmget\0" | |
8130926d LP |
514 | }, |
515 | [SYSCALL_FILTER_SET_KEYRING] = { | |
8130926d | 516 | .name = "@keyring", |
d5efc18b | 517 | .help = "Kernel keyring access", |
1f9ac68b LP |
518 | .value = |
519 | "add_key\0" | |
520 | "keyctl\0" | |
521 | "request_key\0" | |
8130926d | 522 | }, |
cd0ddf6f LP |
523 | [SYSCALL_FILTER_SET_MEMLOCK] = { |
524 | .name = "@memlock", | |
525 | .help = "Memory locking control", | |
526 | .value = | |
527 | "mlock\0" | |
528 | "mlock2\0" | |
529 | "mlockall\0" | |
530 | "munlock\0" | |
531 | "munlockall\0" | |
532 | }, | |
8130926d | 533 | [SYSCALL_FILTER_SET_MODULE] = { |
8130926d | 534 | .name = "@module", |
d5efc18b | 535 | .help = "Loading and unloading of kernel modules", |
201c1cc2 | 536 | .value = |
201c1cc2 TM |
537 | "delete_module\0" |
538 | "finit_module\0" | |
539 | "init_module\0" | |
8130926d LP |
540 | }, |
541 | [SYSCALL_FILTER_SET_MOUNT] = { | |
8130926d | 542 | .name = "@mount", |
d5efc18b | 543 | .help = "Mounting and unmounting of file systems", |
201c1cc2 TM |
544 | .value = |
545 | "chroot\0" | |
546 | "mount\0" | |
201c1cc2 | 547 | "pivot_root\0" |
201c1cc2 | 548 | "umount\0" |
215728ff | 549 | "umount2\0" |
8130926d LP |
550 | }, |
551 | [SYSCALL_FILTER_SET_NETWORK_IO] = { | |
8130926d | 552 | .name = "@network-io", |
d5efc18b | 553 | .help = "Network or Unix socket IO, should not be needed if not network facing", |
201c1cc2 | 554 | .value = |
201c1cc2 | 555 | "accept\0" |
215728ff | 556 | "accept4\0" |
201c1cc2 TM |
557 | "bind\0" |
558 | "connect\0" | |
559 | "getpeername\0" | |
560 | "getsockname\0" | |
561 | "getsockopt\0" | |
562 | "listen\0" | |
563 | "recv\0" | |
564 | "recvfrom\0" | |
565 | "recvmmsg\0" | |
566 | "recvmsg\0" | |
567 | "send\0" | |
568 | "sendmmsg\0" | |
569 | "sendmsg\0" | |
570 | "sendto\0" | |
571 | "setsockopt\0" | |
572 | "shutdown\0" | |
573 | "socket\0" | |
574 | "socketcall\0" | |
575 | "socketpair\0" | |
8130926d LP |
576 | }, |
577 | [SYSCALL_FILTER_SET_OBSOLETE] = { | |
d5efc18b | 578 | /* some unknown even to libseccomp */ |
8130926d | 579 | .name = "@obsolete", |
d5efc18b | 580 | .help = "Unusual, obsolete or unimplemented system calls", |
201c1cc2 TM |
581 | .value = |
582 | "_sysctl\0" | |
583 | "afs_syscall\0" | |
802fa07a | 584 | "bdflush\0" |
201c1cc2 | 585 | "break\0" |
1f9ac68b | 586 | "create_module\0" |
201c1cc2 TM |
587 | "ftime\0" |
588 | "get_kernel_syms\0" | |
201c1cc2 TM |
589 | "getpmsg\0" |
590 | "gtty\0" | |
7e0c3b8f | 591 | "idle\0" |
201c1cc2 | 592 | "lock\0" |
201c1cc2 | 593 | "mpx\0" |
201c1cc2 TM |
594 | "prof\0" |
595 | "profil\0" | |
201c1cc2 TM |
596 | "putpmsg\0" |
597 | "query_module\0" | |
201c1cc2 TM |
598 | "security\0" |
599 | "sgetmask\0" | |
600 | "ssetmask\0" | |
601 | "stty\0" | |
1f9ac68b | 602 | "sysfs\0" |
201c1cc2 TM |
603 | "tuxcall\0" |
604 | "ulimit\0" | |
605 | "uselib\0" | |
1f9ac68b | 606 | "ustat\0" |
201c1cc2 | 607 | "vserver\0" |
8130926d LP |
608 | }, |
609 | [SYSCALL_FILTER_SET_PRIVILEGED] = { | |
8130926d | 610 | .name = "@privileged", |
d5efc18b | 611 | .help = "All system calls which need super-user capabilities", |
201c1cc2 | 612 | .value = |
44898c53 | 613 | "@chown\0" |
201c1cc2 TM |
614 | "@clock\0" |
615 | "@module\0" | |
616 | "@raw-io\0" | |
af0f047b LP |
617 | "@reboot\0" |
618 | "@swap\0" | |
215728ff | 619 | "_sysctl\0" |
201c1cc2 | 620 | "acct\0" |
201c1cc2 | 621 | "bpf\0" |
1f9ac68b | 622 | "capset\0" |
201c1cc2 | 623 | "chroot\0" |
a05cfe23 | 624 | "fanotify_init\0" |
201c1cc2 | 625 | "nfsservctl\0" |
a05cfe23 | 626 | "open_by_handle_at\0" |
201c1cc2 TM |
627 | "pivot_root\0" |
628 | "quotactl\0" | |
201c1cc2 | 629 | "setdomainname\0" |
201c1cc2 | 630 | "setfsuid\0" |
215728ff | 631 | "setfsuid32\0" |
201c1cc2 | 632 | "setgroups\0" |
215728ff | 633 | "setgroups32\0" |
201c1cc2 | 634 | "sethostname\0" |
201c1cc2 | 635 | "setresuid\0" |
215728ff | 636 | "setresuid32\0" |
201c1cc2 | 637 | "setreuid\0" |
215728ff | 638 | "setreuid32\0" |
e05ee49b | 639 | "setuid\0" /* We list the explicit system calls here, as @setuid also includes setgid() which is not necessarily privileged */ |
215728ff | 640 | "setuid32\0" |
201c1cc2 | 641 | "vhangup\0" |
8130926d LP |
642 | }, |
643 | [SYSCALL_FILTER_SET_PROCESS] = { | |
8130926d | 644 | .name = "@process", |
d5efc18b | 645 | .help = "Process control, execution, namespaceing operations", |
201c1cc2 TM |
646 | .value = |
647 | "arch_prctl\0" | |
09d3020b | 648 | "capget\0" /* Able to query arbitrary processes */ |
201c1cc2 | 649 | "clone\0" |
201c1cc2 TM |
650 | "execveat\0" |
651 | "fork\0" | |
b887d2eb | 652 | "getrusage\0" |
201c1cc2 TM |
653 | "kill\0" |
654 | "prctl\0" | |
b887d2eb LP |
655 | "rt_sigqueueinfo\0" |
656 | "rt_tgsigqueueinfo\0" | |
201c1cc2 | 657 | "setns\0" |
a9518dc3 | 658 | "swapcontext\0" /* Some archs e.g. powerpc32 are using it to do userspace context switches */ |
201c1cc2 | 659 | "tgkill\0" |
b887d2eb | 660 | "times\0" |
201c1cc2 TM |
661 | "tkill\0" |
662 | "unshare\0" | |
663 | "vfork\0" | |
b887d2eb LP |
664 | "wait4\0" |
665 | "waitid\0" | |
666 | "waitpid\0" | |
8130926d LP |
667 | }, |
668 | [SYSCALL_FILTER_SET_RAW_IO] = { | |
8130926d | 669 | .name = "@raw-io", |
d5efc18b | 670 | .help = "Raw I/O port access", |
201c1cc2 TM |
671 | .value = |
672 | "ioperm\0" | |
673 | "iopl\0" | |
1f9ac68b | 674 | "pciconfig_iobase\0" |
201c1cc2 TM |
675 | "pciconfig_read\0" |
676 | "pciconfig_write\0" | |
8130926d | 677 | #ifdef __NR_s390_pci_mmio_read |
201c1cc2 | 678 | "s390_pci_mmio_read\0" |
8130926d LP |
679 | #endif |
680 | #ifdef __NR_s390_pci_mmio_write | |
201c1cc2 | 681 | "s390_pci_mmio_write\0" |
8130926d LP |
682 | #endif |
683 | }, | |
bd2ab3f4 LP |
684 | [SYSCALL_FILTER_SET_REBOOT] = { |
685 | .name = "@reboot", | |
686 | .help = "Reboot and reboot preparation/kexec", | |
687 | .value = | |
bd2ab3f4 | 688 | "kexec_file_load\0" |
e59608fa | 689 | "kexec_load\0" |
bd2ab3f4 LP |
690 | "reboot\0" |
691 | }, | |
133ddbbe | 692 | [SYSCALL_FILTER_SET_RESOURCES] = { |
133ddbbe | 693 | .name = "@resources", |
58a8f68b | 694 | .help = "Alter resource settings", |
133ddbbe | 695 | .value = |
0963c053 LP |
696 | "ioprio_set\0" |
697 | "mbind\0" | |
698 | "migrate_pages\0" | |
699 | "move_pages\0" | |
700 | "nice\0" | |
0963c053 LP |
701 | "sched_setaffinity\0" |
702 | "sched_setattr\0" | |
133ddbbe LP |
703 | "sched_setparam\0" |
704 | "sched_setscheduler\0" | |
0963c053 | 705 | "set_mempolicy\0" |
133ddbbe LP |
706 | "setpriority\0" |
707 | "setrlimit\0" | |
133ddbbe | 708 | }, |
6eaaeee9 LP |
709 | [SYSCALL_FILTER_SET_SETUID] = { |
710 | .name = "@setuid", | |
711 | .help = "Operations for changing user/group credentials", | |
712 | .value = | |
6eaaeee9 | 713 | "setgid\0" |
215728ff | 714 | "setgid32\0" |
6eaaeee9 | 715 | "setgroups\0" |
215728ff | 716 | "setgroups32\0" |
6eaaeee9 | 717 | "setregid\0" |
215728ff | 718 | "setregid32\0" |
6eaaeee9 | 719 | "setresgid\0" |
215728ff | 720 | "setresgid32\0" |
6eaaeee9 | 721 | "setresuid\0" |
215728ff | 722 | "setresuid32\0" |
6eaaeee9 | 723 | "setreuid\0" |
215728ff | 724 | "setreuid32\0" |
6eaaeee9 | 725 | "setuid\0" |
215728ff | 726 | "setuid32\0" |
6eaaeee9 | 727 | }, |
cd0ddf6f LP |
728 | [SYSCALL_FILTER_SET_SIGNAL] = { |
729 | .name = "@signal", | |
730 | .help = "Process signal handling", | |
731 | .value = | |
732 | "rt_sigaction\0" | |
733 | "rt_sigpending\0" | |
734 | "rt_sigprocmask\0" | |
735 | "rt_sigsuspend\0" | |
736 | "rt_sigtimedwait\0" | |
737 | "sigaction\0" | |
738 | "sigaltstack\0" | |
739 | "signal\0" | |
740 | "signalfd\0" | |
741 | "signalfd4\0" | |
742 | "sigpending\0" | |
743 | "sigprocmask\0" | |
744 | "sigsuspend\0" | |
745 | }, | |
bd2ab3f4 LP |
746 | [SYSCALL_FILTER_SET_SWAP] = { |
747 | .name = "@swap", | |
748 | .help = "Enable/disable swap devices", | |
749 | .value = | |
750 | "swapoff\0" | |
751 | "swapon\0" | |
752 | }, | |
44898c53 LP |
753 | [SYSCALL_FILTER_SET_SYNC] = { |
754 | .name = "@sync", | |
755 | .help = "Synchronize files and memory to storage", | |
756 | .value = | |
757 | "fdatasync\0" | |
758 | "fsync\0" | |
759 | "msync\0" | |
760 | "sync\0" | |
761 | "sync_file_range\0" | |
762 | "syncfs\0" | |
763 | }, | |
70526841 LP |
764 | [SYSCALL_FILTER_SET_SYSTEM_SERVICE] = { |
765 | .name = "@system-service", | |
766 | .help = "General system service operations", | |
767 | .value = | |
768 | "@aio\0" | |
769 | "@basic-io\0" | |
770 | "@chown\0" | |
771 | "@default\0" | |
772 | "@file-system\0" | |
773 | "@io-event\0" | |
774 | "@ipc\0" | |
775 | "@keyring\0" | |
776 | "@memlock\0" | |
777 | "@network-io\0" | |
778 | "@process\0" | |
779 | "@resources\0" | |
780 | "@setuid\0" | |
781 | "@signal\0" | |
782 | "@sync\0" | |
783 | "@timer\0" | |
784 | "brk\0" | |
785 | "capget\0" | |
786 | "capset\0" | |
787 | "copy_file_range\0" | |
788 | "fadvise64\0" | |
789 | "fadvise64_64\0" | |
790 | "flock\0" | |
791 | "get_mempolicy\0" | |
792 | "getcpu\0" | |
793 | "getpriority\0" | |
794 | "getrandom\0" | |
795 | "ioctl\0" | |
796 | "ioprio_get\0" | |
797 | "kcmp\0" | |
798 | "madvise\0" | |
70526841 LP |
799 | "mprotect\0" |
800 | "mremap\0" | |
801 | "name_to_handle_at\0" | |
802 | "oldolduname\0" | |
803 | "olduname\0" | |
804 | "personality\0" | |
805 | "readahead\0" | |
806 | "readdir\0" | |
807 | "remap_file_pages\0" | |
808 | "sched_get_priority_max\0" | |
809 | "sched_get_priority_min\0" | |
810 | "sched_getaffinity\0" | |
811 | "sched_getattr\0" | |
812 | "sched_getparam\0" | |
813 | "sched_getscheduler\0" | |
814 | "sched_rr_get_interval\0" | |
815 | "sched_yield\0" | |
816 | "sendfile\0" | |
817 | "sendfile64\0" | |
818 | "setfsgid\0" | |
819 | "setfsgid32\0" | |
820 | "setfsuid\0" | |
821 | "setfsuid32\0" | |
822 | "setpgid\0" | |
823 | "setsid\0" | |
824 | "splice\0" | |
825 | "sysinfo\0" | |
826 | "tee\0" | |
827 | "umask\0" | |
828 | "uname\0" | |
829 | "userfaultfd\0" | |
830 | "vmsplice\0" | |
831 | }, | |
cd0ddf6f LP |
832 | [SYSCALL_FILTER_SET_TIMER] = { |
833 | .name = "@timer", | |
834 | .help = "Schedule operations by time", | |
835 | .value = | |
836 | "alarm\0" | |
837 | "getitimer\0" | |
838 | "setitimer\0" | |
839 | "timer_create\0" | |
840 | "timer_delete\0" | |
841 | "timer_getoverrun\0" | |
842 | "timer_gettime\0" | |
843 | "timer_settime\0" | |
844 | "timerfd_create\0" | |
845 | "timerfd_gettime\0" | |
846 | "timerfd_settime\0" | |
847 | "times\0" | |
848 | }, | |
201c1cc2 | 849 | }; |
8130926d LP |
850 | |
851 | const SyscallFilterSet *syscall_filter_set_find(const char *name) { | |
852 | unsigned i; | |
853 | ||
854 | if (isempty(name) || name[0] != '@') | |
855 | return NULL; | |
856 | ||
857 | for (i = 0; i < _SYSCALL_FILTER_SET_MAX; i++) | |
858 | if (streq(syscall_filter_sets[i].name, name)) | |
859 | return syscall_filter_sets + i; | |
860 | ||
861 | return NULL; | |
862 | } | |
863 | ||
b54f36c6 | 864 | static int seccomp_add_syscall_filter_set(scmp_filter_ctx seccomp, const SyscallFilterSet *set, uint32_t action, char **exclude, bool log_missing); |
69b1b241 | 865 | |
b54f36c6 | 866 | int seccomp_add_syscall_filter_item(scmp_filter_ctx *seccomp, const char *name, uint32_t action, char **exclude, bool log_missing) { |
69b1b241 LP |
867 | assert(seccomp); |
868 | assert(name); | |
869 | ||
960e4569 LP |
870 | if (strv_contains(exclude, name)) |
871 | return 0; | |
872 | ||
69b1b241 LP |
873 | if (name[0] == '@') { |
874 | const SyscallFilterSet *other; | |
875 | ||
876 | other = syscall_filter_set_find(name); | |
baaa35ad ZJS |
877 | if (!other) |
878 | return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), | |
879 | "Filter set %s is not known!", | |
880 | name); | |
69b1b241 | 881 | |
b54f36c6 ZJS |
882 | return seccomp_add_syscall_filter_set(seccomp, other, action, exclude, log_missing); |
883 | ||
69b1b241 | 884 | } else { |
b54f36c6 | 885 | int id, r; |
69b1b241 LP |
886 | |
887 | id = seccomp_syscall_resolve_name(name); | |
cff7bff8 | 888 | if (id == __NR_SCMP_ERROR) { |
b54f36c6 ZJS |
889 | if (log_missing) |
890 | log_debug("System call %s is not known, ignoring.", name); | |
ff217dc3 | 891 | return 0; |
cff7bff8 | 892 | } |
69b1b241 LP |
893 | |
894 | r = seccomp_rule_add_exact(seccomp, action, id, 0); | |
b54f36c6 | 895 | if (r < 0) { |
69b1b241 | 896 | /* If the system call is not known on this architecture, then that's fine, let's ignore it */ |
7e86bd73 ZJS |
897 | bool ignore = r == -EDOM; |
898 | ||
899 | if (!ignore || log_missing) | |
900 | log_debug_errno(r, "Failed to add rule for system call %s() / %d%s: %m", | |
901 | name, id, ignore ? ", ignoring" : ""); | |
902 | if (!ignore) | |
903 | return r; | |
b54f36c6 | 904 | } |
69b1b241 | 905 | |
b54f36c6 ZJS |
906 | return 0; |
907 | } | |
69b1b241 LP |
908 | } |
909 | ||
469830d1 LP |
910 | static int seccomp_add_syscall_filter_set( |
911 | scmp_filter_ctx seccomp, | |
469830d1 | 912 | const SyscallFilterSet *set, |
960e4569 | 913 | uint32_t action, |
b54f36c6 ZJS |
914 | char **exclude, |
915 | bool log_missing) { | |
469830d1 | 916 | |
8130926d LP |
917 | const char *sys; |
918 | int r; | |
919 | ||
920 | assert(seccomp); | |
921 | assert(set); | |
922 | ||
923 | NULSTR_FOREACH(sys, set->value) { | |
b54f36c6 | 924 | r = seccomp_add_syscall_filter_item(seccomp, sys, action, exclude, log_missing); |
69b1b241 LP |
925 | if (r < 0) |
926 | return r; | |
469830d1 LP |
927 | } |
928 | ||
929 | return 0; | |
930 | } | |
931 | ||
b54f36c6 | 932 | int seccomp_load_syscall_filter_set(uint32_t default_action, const SyscallFilterSet *set, uint32_t action, bool log_missing) { |
469830d1 LP |
933 | uint32_t arch; |
934 | int r; | |
935 | ||
936 | assert(set); | |
937 | ||
938 | /* The one-stop solution: allocate a seccomp object, add the specified filter to it, and apply it. Once for | |
a90db619 | 939 | * each local arch. */ |
469830d1 LP |
940 | |
941 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { | |
942 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
943 | ||
944 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); | |
945 | ||
946 | r = seccomp_init_for_arch(&seccomp, arch, default_action); | |
8130926d LP |
947 | if (r < 0) |
948 | return r; | |
469830d1 | 949 | |
b54f36c6 | 950 | r = seccomp_add_syscall_filter_set(seccomp, set, action, NULL, log_missing); |
7e86bd73 ZJS |
951 | if (r < 0) |
952 | return log_debug_errno(r, "Failed to add filter set: %m"); | |
469830d1 LP |
953 | |
954 | r = seccomp_load(seccomp); | |
955 | if (IN_SET(r, -EPERM, -EACCES)) | |
956 | return r; | |
957 | if (r < 0) | |
958 | log_debug_errno(r, "Failed to install filter set for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
8130926d LP |
959 | } |
960 | ||
961 | return 0; | |
962 | } | |
a3be2849 | 963 | |
b54f36c6 | 964 | int seccomp_load_syscall_filter_set_raw(uint32_t default_action, Hashmap* set, uint32_t action, bool log_missing) { |
469830d1 | 965 | uint32_t arch; |
a3be2849 LP |
966 | int r; |
967 | ||
469830d1 LP |
968 | /* Similar to seccomp_load_syscall_filter_set(), but takes a raw Set* of syscalls, instead of a |
969 | * SyscallFilterSet* table. */ | |
a3be2849 | 970 | |
8cfa775f | 971 | if (hashmap_isempty(set) && default_action == SCMP_ACT_ALLOW) |
469830d1 | 972 | return 0; |
a3be2849 | 973 | |
469830d1 LP |
974 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { |
975 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
976 | Iterator i; | |
b54f36c6 | 977 | void *syscall_id, *val; |
a3be2849 | 978 | |
469830d1 | 979 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); |
a3be2849 | 980 | |
469830d1 LP |
981 | r = seccomp_init_for_arch(&seccomp, arch, default_action); |
982 | if (r < 0) | |
983 | return r; | |
a3be2849 | 984 | |
b54f36c6 | 985 | HASHMAP_FOREACH_KEY(val, syscall_id, set, i) { |
8cfa775f | 986 | uint32_t a = action; |
b54f36c6 ZJS |
987 | int id = PTR_TO_INT(syscall_id) - 1; |
988 | int error = PTR_TO_INT(val); | |
8cfa775f | 989 | |
b54f36c6 ZJS |
990 | if (action != SCMP_ACT_ALLOW && error >= 0) |
991 | a = SCMP_ACT_ERRNO(error); | |
8cfa775f | 992 | |
b54f36c6 | 993 | r = seccomp_rule_add_exact(seccomp, a, id, 0); |
469830d1 LP |
994 | if (r < 0) { |
995 | /* If the system call is not known on this architecture, then that's fine, let's ignore it */ | |
996 | _cleanup_free_ char *n = NULL; | |
7e86bd73 | 997 | bool ignore; |
469830d1 | 998 | |
b54f36c6 | 999 | n = seccomp_syscall_resolve_num_arch(SCMP_ARCH_NATIVE, id); |
7e86bd73 ZJS |
1000 | ignore = r == -EDOM; |
1001 | if (!ignore || log_missing) | |
1002 | log_debug_errno(r, "Failed to add rule for system call %s() / %d%s: %m", | |
1003 | strna(n), id, ignore ? ", ignoring" : ""); | |
1004 | if (!ignore) | |
1005 | return r; | |
469830d1 LP |
1006 | } |
1007 | } | |
1008 | ||
1009 | r = seccomp_load(seccomp); | |
1010 | if (IN_SET(r, -EPERM, -EACCES)) | |
1011 | return r; | |
1012 | if (r < 0) | |
1013 | log_debug_errno(r, "Failed to install filter set for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1014 | } | |
1015 | ||
1016 | return 0; | |
add00535 LP |
1017 | } |
1018 | ||
58f6ab44 | 1019 | int seccomp_parse_syscall_filter( |
898748d8 YW |
1020 | const char *name, |
1021 | int errno_num, | |
1022 | Hashmap *filter, | |
13d92c63 | 1023 | SeccompParseFlags flags, |
898748d8 YW |
1024 | const char *unit, |
1025 | const char *filename, | |
1026 | unsigned line) { | |
1027 | ||
1028 | int r; | |
1029 | ||
1030 | assert(name); | |
1031 | assert(filter); | |
1032 | ||
1033 | if (name[0] == '@') { | |
1034 | const SyscallFilterSet *set; | |
1035 | const char *i; | |
1036 | ||
1037 | set = syscall_filter_set_find(name); | |
1038 | if (!set) { | |
13d92c63 | 1039 | if (!(flags & SECCOMP_PARSE_PERMISSIVE)) |
898748d8 | 1040 | return -EINVAL; |
13d92c63 LP |
1041 | |
1042 | log_syntax(unit, flags & SECCOMP_PARSE_LOG ? LOG_WARNING : LOG_DEBUG, filename, line, 0, | |
1043 | "Unknown system call group, ignoring: %s", name); | |
1044 | return 0; | |
898748d8 YW |
1045 | } |
1046 | ||
1047 | NULSTR_FOREACH(i, set->value) { | |
13d92c63 LP |
1048 | /* Call ourselves again, for the group to parse. Note that we downgrade logging here (i.e. take |
1049 | * away the SECCOMP_PARSE_LOG flag) since any issues in the group table are our own problem, | |
1050 | * not a problem in user configuration data and we shouldn't pretend otherwise by complaining | |
1051 | * about them. */ | |
58f6ab44 | 1052 | r = seccomp_parse_syscall_filter(i, errno_num, filter, flags &~ SECCOMP_PARSE_LOG, unit, filename, line); |
898748d8 YW |
1053 | if (r < 0) |
1054 | return r; | |
1055 | } | |
1056 | } else { | |
1057 | int id; | |
1058 | ||
1059 | id = seccomp_syscall_resolve_name(name); | |
1060 | if (id == __NR_SCMP_ERROR) { | |
13d92c63 | 1061 | if (!(flags & SECCOMP_PARSE_PERMISSIVE)) |
898748d8 | 1062 | return -EINVAL; |
13d92c63 LP |
1063 | |
1064 | log_syntax(unit, flags & SECCOMP_PARSE_LOG ? LOG_WARNING : LOG_DEBUG, filename, line, 0, | |
1065 | "Failed to parse system call, ignoring: %s", name); | |
1066 | return 0; | |
898748d8 YW |
1067 | } |
1068 | ||
1069 | /* If we previously wanted to forbid a syscall and now | |
1070 | * we want to allow it, then remove it from the list. */ | |
13d92c63 | 1071 | if (!(flags & SECCOMP_PARSE_INVERT) == !!(flags & SECCOMP_PARSE_WHITELIST)) { |
898748d8 YW |
1072 | r = hashmap_put(filter, INT_TO_PTR(id + 1), INT_TO_PTR(errno_num)); |
1073 | if (r < 0) | |
851ee70a LW |
1074 | switch (r) { |
1075 | case -ENOMEM: | |
1076 | return flags & SECCOMP_PARSE_LOG ? log_oom() : -ENOMEM; | |
1077 | case -EEXIST: | |
9d7fe7c6 LW |
1078 | assert_se(hashmap_update(filter, INT_TO_PTR(id + 1), INT_TO_PTR(errno_num)) == 0); |
1079 | break; | |
851ee70a LW |
1080 | default: |
1081 | return r; | |
1082 | } | |
898748d8 YW |
1083 | } else |
1084 | (void) hashmap_remove(filter, INT_TO_PTR(id + 1)); | |
1085 | } | |
1086 | ||
1087 | return 0; | |
1088 | } | |
1089 | ||
add00535 | 1090 | int seccomp_restrict_namespaces(unsigned long retain) { |
469830d1 | 1091 | uint32_t arch; |
add00535 LP |
1092 | int r; |
1093 | ||
f1d34068 | 1094 | if (DEBUG_LOGGING) { |
add00535 LP |
1095 | _cleanup_free_ char *s = NULL; |
1096 | ||
86c2a9f1 | 1097 | (void) namespace_flags_to_string(retain, &s); |
add00535 LP |
1098 | log_debug("Restricting namespace to: %s.", strna(s)); |
1099 | } | |
1100 | ||
1101 | /* NOOP? */ | |
1102 | if ((retain & NAMESPACE_FLAGS_ALL) == NAMESPACE_FLAGS_ALL) | |
1103 | return 0; | |
1104 | ||
469830d1 LP |
1105 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { |
1106 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
1107 | unsigned i; | |
add00535 | 1108 | |
469830d1 LP |
1109 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); |
1110 | ||
1111 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); | |
1112 | if (r < 0) | |
1113 | return r; | |
1114 | ||
1115 | if ((retain & NAMESPACE_FLAGS_ALL) == 0) | |
1116 | /* If every single kind of namespace shall be prohibited, then let's block the whole setns() syscall | |
1117 | * altogether. */ | |
1118 | r = seccomp_rule_add_exact( | |
1119 | seccomp, | |
1120 | SCMP_ACT_ERRNO(EPERM), | |
1121 | SCMP_SYS(setns), | |
1122 | 0); | |
1123 | else | |
1124 | /* Otherwise, block only the invocations with the appropriate flags in the loop below, but also the | |
1125 | * special invocation with a zero flags argument, right here. */ | |
1126 | r = seccomp_rule_add_exact( | |
1127 | seccomp, | |
1128 | SCMP_ACT_ERRNO(EPERM), | |
1129 | SCMP_SYS(setns), | |
1130 | 1, | |
1131 | SCMP_A1(SCMP_CMP_EQ, 0)); | |
1132 | if (r < 0) { | |
1133 | log_debug_errno(r, "Failed to add setns() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1134 | continue; | |
1135 | } | |
1136 | ||
1137 | for (i = 0; namespace_flag_map[i].name; i++) { | |
1138 | unsigned long f; | |
1139 | ||
1140 | f = namespace_flag_map[i].flag; | |
1141 | if ((retain & f) == f) { | |
1142 | log_debug("Permitting %s.", namespace_flag_map[i].name); | |
1143 | continue; | |
1144 | } | |
1145 | ||
1146 | log_debug("Blocking %s.", namespace_flag_map[i].name); | |
1147 | ||
1148 | r = seccomp_rule_add_exact( | |
1149 | seccomp, | |
1150 | SCMP_ACT_ERRNO(EPERM), | |
1151 | SCMP_SYS(unshare), | |
1152 | 1, | |
1153 | SCMP_A0(SCMP_CMP_MASKED_EQ, f, f)); | |
1154 | if (r < 0) { | |
1155 | log_debug_errno(r, "Failed to add unshare() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1156 | break; | |
1157 | } | |
1158 | ||
511ceb1f ZJS |
1159 | /* On s390/s390x the first two parameters to clone are switched */ |
1160 | if (!IN_SET(arch, SCMP_ARCH_S390, SCMP_ARCH_S390X)) | |
ae9d60ce LP |
1161 | r = seccomp_rule_add_exact( |
1162 | seccomp, | |
1163 | SCMP_ACT_ERRNO(EPERM), | |
1164 | SCMP_SYS(clone), | |
1165 | 1, | |
1166 | SCMP_A0(SCMP_CMP_MASKED_EQ, f, f)); | |
1167 | else | |
1168 | r = seccomp_rule_add_exact( | |
1169 | seccomp, | |
1170 | SCMP_ACT_ERRNO(EPERM), | |
1171 | SCMP_SYS(clone), | |
1172 | 1, | |
1173 | SCMP_A1(SCMP_CMP_MASKED_EQ, f, f)); | |
469830d1 LP |
1174 | if (r < 0) { |
1175 | log_debug_errno(r, "Failed to add clone() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1176 | break; | |
1177 | } | |
1178 | ||
1179 | if ((retain & NAMESPACE_FLAGS_ALL) != 0) { | |
1180 | r = seccomp_rule_add_exact( | |
1181 | seccomp, | |
1182 | SCMP_ACT_ERRNO(EPERM), | |
1183 | SCMP_SYS(setns), | |
1184 | 1, | |
1185 | SCMP_A1(SCMP_CMP_MASKED_EQ, f, f)); | |
1186 | if (r < 0) { | |
1187 | log_debug_errno(r, "Failed to add setns() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1188 | break; | |
1189 | } | |
1190 | } | |
1191 | } | |
1192 | if (r < 0) | |
1193 | continue; | |
1194 | ||
1195 | r = seccomp_load(seccomp); | |
1196 | if (IN_SET(r, -EPERM, -EACCES)) | |
1197 | return r; | |
1198 | if (r < 0) | |
1199 | log_debug_errno(r, "Failed to install namespace restriction rules for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1200 | } | |
1201 | ||
1202 | return 0; | |
1203 | } | |
1204 | ||
1205 | int seccomp_protect_sysctl(void) { | |
1206 | uint32_t arch; | |
1207 | int r; | |
1208 | ||
1209 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { | |
1210 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
1211 | ||
1212 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); | |
1213 | ||
2e64e8f4 ZJS |
1214 | if (IN_SET(arch, SCMP_ARCH_X32, SCMP_ARCH_AARCH64)) |
1215 | /* No _sysctl syscall */ | |
1216 | continue; | |
1217 | ||
469830d1 LP |
1218 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); |
1219 | if (r < 0) | |
1220 | return r; | |
1221 | ||
1222 | r = seccomp_rule_add_exact( | |
add00535 LP |
1223 | seccomp, |
1224 | SCMP_ACT_ERRNO(EPERM), | |
469830d1 | 1225 | SCMP_SYS(_sysctl), |
add00535 | 1226 | 0); |
469830d1 LP |
1227 | if (r < 0) { |
1228 | log_debug_errno(r, "Failed to add _sysctl() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1229 | continue; | |
1230 | } | |
1231 | ||
1232 | r = seccomp_load(seccomp); | |
1233 | if (IN_SET(r, -EPERM, -EACCES)) | |
1234 | return r; | |
1235 | if (r < 0) | |
1236 | log_debug_errno(r, "Failed to install sysctl protection rules for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1237 | } | |
1238 | ||
1239 | return 0; | |
1240 | } | |
1241 | ||
1242 | int seccomp_restrict_address_families(Set *address_families, bool whitelist) { | |
1243 | uint32_t arch; | |
1244 | int r; | |
1245 | ||
1246 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { | |
1247 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
9606bc4b | 1248 | bool supported; |
469830d1 LP |
1249 | Iterator i; |
1250 | ||
1251 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); | |
1252 | ||
9606bc4b LP |
1253 | switch (arch) { |
1254 | ||
1255 | case SCMP_ARCH_X86_64: | |
1256 | case SCMP_ARCH_X32: | |
1257 | case SCMP_ARCH_ARM: | |
1258 | case SCMP_ARCH_AARCH64: | |
0d9fca76 | 1259 | case SCMP_ARCH_PPC: |
da1921a5 ZJS |
1260 | case SCMP_ARCH_PPC64: |
1261 | case SCMP_ARCH_PPC64LE: | |
f5aeac14 JC |
1262 | case SCMP_ARCH_MIPSEL64N32: |
1263 | case SCMP_ARCH_MIPS64N32: | |
1264 | case SCMP_ARCH_MIPSEL64: | |
1265 | case SCMP_ARCH_MIPS64: | |
9606bc4b LP |
1266 | /* These we know we support (i.e. are the ones that do not use socketcall()) */ |
1267 | supported = true; | |
1268 | break; | |
1269 | ||
9606bc4b LP |
1270 | case SCMP_ARCH_S390: |
1271 | case SCMP_ARCH_S390X: | |
da1921a5 | 1272 | case SCMP_ARCH_X86: |
f5aeac14 JC |
1273 | case SCMP_ARCH_MIPSEL: |
1274 | case SCMP_ARCH_MIPS: | |
9606bc4b LP |
1275 | default: |
1276 | /* These we either know we don't support (i.e. are the ones that do use socketcall()), or we | |
1277 | * don't know */ | |
1278 | supported = false; | |
1279 | break; | |
1280 | } | |
1281 | ||
1282 | if (!supported) | |
1283 | continue; | |
1284 | ||
469830d1 LP |
1285 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); |
1286 | if (r < 0) | |
1287 | return r; | |
1288 | ||
1289 | if (whitelist) { | |
1290 | int af, first = 0, last = 0; | |
1291 | void *afp; | |
1292 | ||
1293 | /* If this is a whitelist, we first block the address families that are out of range and then | |
1294 | * everything that is not in the set. First, we find the lowest and highest address family in | |
1295 | * the set. */ | |
1296 | ||
1297 | SET_FOREACH(afp, address_families, i) { | |
1298 | af = PTR_TO_INT(afp); | |
1299 | ||
1300 | if (af <= 0 || af >= af_max()) | |
1301 | continue; | |
1302 | ||
1303 | if (first == 0 || af < first) | |
1304 | first = af; | |
1305 | ||
1306 | if (last == 0 || af > last) | |
1307 | last = af; | |
1308 | } | |
1309 | ||
1310 | assert((first == 0) == (last == 0)); | |
1311 | ||
1312 | if (first == 0) { | |
1313 | ||
1314 | /* No entries in the valid range, block everything */ | |
1315 | r = seccomp_rule_add_exact( | |
1316 | seccomp, | |
1317 | SCMP_ACT_ERRNO(EAFNOSUPPORT), | |
1318 | SCMP_SYS(socket), | |
1319 | 0); | |
1320 | if (r < 0) { | |
1321 | log_debug_errno(r, "Failed to add socket() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1322 | continue; | |
1323 | } | |
1324 | ||
1325 | } else { | |
1326 | ||
1327 | /* Block everything below the first entry */ | |
1328 | r = seccomp_rule_add_exact( | |
1329 | seccomp, | |
1330 | SCMP_ACT_ERRNO(EAFNOSUPPORT), | |
1331 | SCMP_SYS(socket), | |
1332 | 1, | |
1333 | SCMP_A0(SCMP_CMP_LT, first)); | |
1334 | if (r < 0) { | |
1335 | log_debug_errno(r, "Failed to add socket() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1336 | continue; | |
1337 | } | |
1338 | ||
1339 | /* Block everything above the last entry */ | |
1340 | r = seccomp_rule_add_exact( | |
1341 | seccomp, | |
1342 | SCMP_ACT_ERRNO(EAFNOSUPPORT), | |
1343 | SCMP_SYS(socket), | |
1344 | 1, | |
1345 | SCMP_A0(SCMP_CMP_GT, last)); | |
1346 | if (r < 0) { | |
1347 | log_debug_errno(r, "Failed to add socket() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1348 | continue; | |
1349 | } | |
1350 | ||
1351 | /* Block everything between the first and last entry */ | |
1352 | for (af = 1; af < af_max(); af++) { | |
1353 | ||
1354 | if (set_contains(address_families, INT_TO_PTR(af))) | |
1355 | continue; | |
1356 | ||
1357 | r = seccomp_rule_add_exact( | |
1358 | seccomp, | |
1359 | SCMP_ACT_ERRNO(EAFNOSUPPORT), | |
1360 | SCMP_SYS(socket), | |
1361 | 1, | |
1362 | SCMP_A0(SCMP_CMP_EQ, af)); | |
1363 | if (r < 0) | |
1364 | break; | |
1365 | } | |
469830d1 LP |
1366 | if (r < 0) { |
1367 | log_debug_errno(r, "Failed to add socket() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1368 | continue; | |
1369 | } | |
1370 | } | |
1371 | ||
1372 | } else { | |
1373 | void *af; | |
1374 | ||
1375 | /* If this is a blacklist, then generate one rule for | |
1376 | * each address family that are then combined in OR | |
1377 | * checks. */ | |
1378 | ||
1379 | SET_FOREACH(af, address_families, i) { | |
1380 | ||
1381 | r = seccomp_rule_add_exact( | |
1382 | seccomp, | |
1383 | SCMP_ACT_ERRNO(EAFNOSUPPORT), | |
1384 | SCMP_SYS(socket), | |
1385 | 1, | |
1386 | SCMP_A0(SCMP_CMP_EQ, PTR_TO_INT(af))); | |
1387 | if (r < 0) | |
1388 | break; | |
1389 | } | |
469830d1 LP |
1390 | if (r < 0) { |
1391 | log_debug_errno(r, "Failed to add socket() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1392 | continue; | |
1393 | } | |
1394 | } | |
1395 | ||
1396 | r = seccomp_load(seccomp); | |
1397 | if (IN_SET(r, -EPERM, -EACCES)) | |
1398 | return r; | |
1399 | if (r < 0) | |
1400 | log_debug_errno(r, "Failed to install socket family rules for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1401 | } | |
1402 | ||
1403 | return 0; | |
1404 | } | |
1405 | ||
1406 | int seccomp_restrict_realtime(void) { | |
1407 | static const int permitted_policies[] = { | |
1408 | SCHED_OTHER, | |
1409 | SCHED_BATCH, | |
1410 | SCHED_IDLE, | |
1411 | }; | |
1412 | ||
1413 | int r, max_policy = 0; | |
1414 | uint32_t arch; | |
1415 | unsigned i; | |
1416 | ||
1417 | /* Determine the highest policy constant we want to allow */ | |
1418 | for (i = 0; i < ELEMENTSOF(permitted_policies); i++) | |
1419 | if (permitted_policies[i] > max_policy) | |
1420 | max_policy = permitted_policies[i]; | |
1421 | ||
1422 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { | |
1423 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
1424 | int p; | |
1425 | ||
1426 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); | |
1427 | ||
1428 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); | |
1429 | if (r < 0) | |
1430 | return r; | |
1431 | ||
1432 | /* Go through all policies with lower values than that, and block them -- unless they appear in the | |
1433 | * whitelist. */ | |
1434 | for (p = 0; p < max_policy; p++) { | |
1435 | bool good = false; | |
1436 | ||
1437 | /* Check if this is in the whitelist. */ | |
1438 | for (i = 0; i < ELEMENTSOF(permitted_policies); i++) | |
1439 | if (permitted_policies[i] == p) { | |
1440 | good = true; | |
1441 | break; | |
1442 | } | |
1443 | ||
1444 | if (good) | |
1445 | continue; | |
1446 | ||
1447 | /* Deny this policy */ | |
1448 | r = seccomp_rule_add_exact( | |
1449 | seccomp, | |
1450 | SCMP_ACT_ERRNO(EPERM), | |
1451 | SCMP_SYS(sched_setscheduler), | |
1452 | 1, | |
1453 | SCMP_A1(SCMP_CMP_EQ, p)); | |
1454 | if (r < 0) { | |
1455 | log_debug_errno(r, "Failed to add scheduler rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1456 | continue; | |
1457 | } | |
1458 | } | |
1459 | ||
1460 | /* Blacklist all other policies, i.e. the ones with higher values. Note that all comparisons are | |
1461 | * unsigned here, hence no need no check for < 0 values. */ | |
1462 | r = seccomp_rule_add_exact( | |
add00535 LP |
1463 | seccomp, |
1464 | SCMP_ACT_ERRNO(EPERM), | |
469830d1 | 1465 | SCMP_SYS(sched_setscheduler), |
add00535 | 1466 | 1, |
469830d1 LP |
1467 | SCMP_A1(SCMP_CMP_GT, max_policy)); |
1468 | if (r < 0) { | |
1469 | log_debug_errno(r, "Failed to add scheduler rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1470 | continue; | |
1471 | } | |
add00535 | 1472 | |
469830d1 LP |
1473 | r = seccomp_load(seccomp); |
1474 | if (IN_SET(r, -EPERM, -EACCES)) | |
1475 | return r; | |
1476 | if (r < 0) | |
1477 | log_debug_errno(r, "Failed to install realtime protection rules for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1478 | } | |
1479 | ||
1480 | return 0; | |
1481 | } | |
1482 | ||
6dc66688 ZJS |
1483 | static int add_seccomp_syscall_filter(scmp_filter_ctx seccomp, |
1484 | uint32_t arch, | |
1485 | int nr, | |
14cb109d | 1486 | unsigned arg_cnt, |
6dc66688 ZJS |
1487 | const struct scmp_arg_cmp arg) { |
1488 | int r; | |
1489 | ||
1490 | r = seccomp_rule_add_exact(seccomp, SCMP_ACT_ERRNO(EPERM), nr, arg_cnt, arg); | |
1491 | if (r < 0) { | |
1492 | _cleanup_free_ char *n = NULL; | |
1493 | ||
1494 | n = seccomp_syscall_resolve_num_arch(arch, nr); | |
1495 | log_debug_errno(r, "Failed to add %s() rule for architecture %s, skipping: %m", | |
1496 | strna(n), | |
1497 | seccomp_arch_to_string(arch)); | |
1498 | } | |
1499 | ||
1500 | return r; | |
1501 | } | |
1502 | ||
2a8d6e63 | 1503 | /* For known architectures, check that syscalls are indeed defined or not. */ |
303d6b4c | 1504 | #if defined(__x86_64__) || defined(__arm__) || defined(__aarch64__) |
2a8d6e63 ZJS |
1505 | assert_cc(SCMP_SYS(shmget) > 0); |
1506 | assert_cc(SCMP_SYS(shmat) > 0); | |
1507 | assert_cc(SCMP_SYS(shmdt) > 0); | |
2a8d6e63 | 1508 | #endif |
6dc66688 | 1509 | |
469830d1 LP |
1510 | int seccomp_memory_deny_write_execute(void) { |
1511 | uint32_t arch; | |
1512 | int r; | |
1513 | ||
1514 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { | |
1515 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
8a50cf69 | 1516 | int filter_syscall = 0, block_syscall = 0, shmat_syscall = 0; |
add00535 | 1517 | |
469830d1 LP |
1518 | log_debug("Operating on architecture: %s", seccomp_arch_to_string(arch)); |
1519 | ||
8a50cf69 LP |
1520 | switch (arch) { |
1521 | ||
1522 | case SCMP_ARCH_X86: | |
1523 | filter_syscall = SCMP_SYS(mmap2); | |
1524 | block_syscall = SCMP_SYS(mmap); | |
67fb5f33 | 1525 | shmat_syscall = SCMP_SYS(shmat); |
2a8d6e63 ZJS |
1526 | break; |
1527 | ||
63d00dfb | 1528 | case SCMP_ARCH_PPC: |
2a8d6e63 ZJS |
1529 | case SCMP_ARCH_PPC64: |
1530 | case SCMP_ARCH_PPC64LE: | |
1531 | filter_syscall = SCMP_SYS(mmap); | |
1532 | ||
1533 | /* Note that shmat() isn't available, and the call is multiplexed through ipc(). | |
1534 | * We ignore that here, which means there's still a way to get writable/executable | |
1535 | * memory, if an IPC key is mapped like this. That's a pity, but no total loss. */ | |
8a50cf69 | 1536 | |
8a50cf69 LP |
1537 | break; |
1538 | ||
4278d1f5 ZJS |
1539 | case SCMP_ARCH_ARM: |
1540 | filter_syscall = SCMP_SYS(mmap2); /* arm has only mmap2 */ | |
1541 | shmat_syscall = SCMP_SYS(shmat); | |
1542 | break; | |
1543 | ||
8a50cf69 LP |
1544 | case SCMP_ARCH_X86_64: |
1545 | case SCMP_ARCH_X32: | |
79873bc8 | 1546 | case SCMP_ARCH_AARCH64: |
303d6b4c | 1547 | filter_syscall = SCMP_SYS(mmap); /* amd64, x32, and arm64 have only mmap */ |
8a50cf69 LP |
1548 | shmat_syscall = SCMP_SYS(shmat); |
1549 | break; | |
1550 | ||
1551 | /* Please add more definitions here, if you port systemd to other architectures! */ | |
1552 | ||
303d6b4c | 1553 | #if !defined(__i386__) && !defined(__x86_64__) && !defined(__powerpc__) && !defined(__powerpc64__) && !defined(__arm__) && !defined(__aarch64__) |
8a50cf69 LP |
1554 | #warning "Consider adding the right mmap() syscall definitions here!" |
1555 | #endif | |
1556 | } | |
1557 | ||
1558 | /* Can't filter mmap() on this arch, then skip it */ | |
1559 | if (filter_syscall == 0) | |
1560 | continue; | |
1561 | ||
469830d1 LP |
1562 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); |
1563 | if (r < 0) | |
1564 | return r; | |
1565 | ||
6dc66688 ZJS |
1566 | r = add_seccomp_syscall_filter(seccomp, arch, filter_syscall, |
1567 | 1, | |
1568 | SCMP_A2(SCMP_CMP_MASKED_EQ, PROT_EXEC|PROT_WRITE, PROT_EXEC|PROT_WRITE)); | |
1569 | if (r < 0) | |
1570 | continue; | |
8a50cf69 LP |
1571 | |
1572 | if (block_syscall != 0) { | |
6dc66688 ZJS |
1573 | r = add_seccomp_syscall_filter(seccomp, arch, block_syscall, 0, (const struct scmp_arg_cmp){} ); |
1574 | if (r < 0) | |
8a50cf69 | 1575 | continue; |
add00535 | 1576 | } |
a3be2849 | 1577 | |
6dc66688 ZJS |
1578 | r = add_seccomp_syscall_filter(seccomp, arch, SCMP_SYS(mprotect), |
1579 | 1, | |
b835eeb4 ZJS |
1580 | SCMP_A2(SCMP_CMP_MASKED_EQ, PROT_EXEC, PROT_EXEC)); |
1581 | if (r < 0) | |
1582 | continue; | |
1583 | ||
91691f1d | 1584 | #ifdef __NR_pkey_mprotect |
b835eeb4 ZJS |
1585 | r = add_seccomp_syscall_filter(seccomp, arch, SCMP_SYS(pkey_mprotect), |
1586 | 1, | |
6dc66688 ZJS |
1587 | SCMP_A2(SCMP_CMP_MASKED_EQ, PROT_EXEC, PROT_EXEC)); |
1588 | if (r < 0) | |
469830d1 | 1589 | continue; |
91691f1d | 1590 | #endif |
add00535 | 1591 | |
67fb5f33 | 1592 | if (shmat_syscall > 0) { |
6dc66688 ZJS |
1593 | r = add_seccomp_syscall_filter(seccomp, arch, SCMP_SYS(shmat), |
1594 | 1, | |
1595 | SCMP_A2(SCMP_CMP_MASKED_EQ, SHM_EXEC, SHM_EXEC)); | |
1596 | if (r < 0) | |
8a50cf69 | 1597 | continue; |
469830d1 LP |
1598 | } |
1599 | ||
1600 | r = seccomp_load(seccomp); | |
1601 | if (IN_SET(r, -EPERM, -EACCES)) | |
1602 | return r; | |
add00535 | 1603 | if (r < 0) |
469830d1 LP |
1604 | log_debug_errno(r, "Failed to install MemoryDenyWriteExecute= rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); |
1605 | } | |
add00535 | 1606 | |
469830d1 LP |
1607 | return 0; |
1608 | } | |
1609 | ||
1610 | int seccomp_restrict_archs(Set *archs) { | |
1611 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
1612 | Iterator i; | |
1613 | void *id; | |
1614 | int r; | |
1615 | ||
1616 | /* This installs a filter with no rules, but that restricts the system call architectures to the specified | |
2428aaf8 AJ |
1617 | * list. |
1618 | * | |
1619 | * There are some qualifications. However the most important use is to stop processes from bypassing | |
1620 | * system call restrictions, in case they used a broader (multiplexing) syscall which is only available | |
1621 | * in a non-native architecture. There are no holes in this use case, at least so far. */ | |
469830d1 | 1622 | |
2428aaf8 AJ |
1623 | /* Note libseccomp includes our "native" (current) architecture in the filter by default. |
1624 | * We do not remove it. For example, our callers expect to be able to call execve() afterwards | |
1625 | * to run a program with the restrictions applied. */ | |
469830d1 LP |
1626 | seccomp = seccomp_init(SCMP_ACT_ALLOW); |
1627 | if (!seccomp) | |
1628 | return -ENOMEM; | |
1629 | ||
1630 | SET_FOREACH(id, archs, i) { | |
1631 | r = seccomp_arch_add(seccomp, PTR_TO_UINT32(id) - 1); | |
2428aaf8 AJ |
1632 | if (r < 0 && r != -EEXIST) |
1633 | return r; | |
1634 | } | |
1635 | ||
1636 | /* The vdso for x32 assumes that x86-64 syscalls are available. Let's allow them, since x32 | |
1637 | * x32 syscalls should basically match x86-64 for everything except the pointer type. | |
1638 | * The important thing is that you can block the old 32-bit x86 syscalls. | |
1639 | * https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=850047 */ | |
1640 | ||
1641 | if (seccomp_arch_native() == SCMP_ARCH_X32 || | |
1642 | set_contains(archs, UINT32_TO_PTR(SCMP_ARCH_X32 + 1))) { | |
1643 | ||
1644 | r = seccomp_arch_add(seccomp, SCMP_ARCH_X86_64); | |
1645 | if (r < 0 && r != -EEXIST) | |
469830d1 | 1646 | return r; |
add00535 LP |
1647 | } |
1648 | ||
469830d1 LP |
1649 | r = seccomp_attr_set(seccomp, SCMP_FLTATR_CTL_NNP, 0); |
1650 | if (r < 0) | |
1651 | return r; | |
add00535 | 1652 | |
1c6af69b LP |
1653 | r = seccomp_load(seccomp); |
1654 | if (IN_SET(r, -EPERM, -EACCES)) | |
1655 | return r; | |
1656 | if (r < 0) | |
1657 | log_debug_errno(r, "Failed to restrict system call architectures, skipping: %m"); | |
1658 | ||
1659 | return 0; | |
a3be2849 | 1660 | } |
b16bd535 YW |
1661 | |
1662 | int parse_syscall_archs(char **l, Set **archs) { | |
1663 | _cleanup_set_free_ Set *_archs; | |
1664 | char **s; | |
1665 | int r; | |
1666 | ||
1667 | assert(l); | |
1668 | assert(archs); | |
1669 | ||
1670 | r = set_ensure_allocated(&_archs, NULL); | |
1671 | if (r < 0) | |
1672 | return r; | |
1673 | ||
1674 | STRV_FOREACH(s, l) { | |
1675 | uint32_t a; | |
1676 | ||
1677 | r = seccomp_arch_from_string(*s, &a); | |
1678 | if (r < 0) | |
1679 | return -EINVAL; | |
1680 | ||
1681 | r = set_put(_archs, UINT32_TO_PTR(a + 1)); | |
1682 | if (r < 0) | |
1683 | return -ENOMEM; | |
1684 | } | |
1685 | ||
1cc6c93a | 1686 | *archs = TAKE_PTR(_archs); |
b16bd535 YW |
1687 | |
1688 | return 0; | |
1689 | } | |
165a31c0 | 1690 | |
8cfa775f | 1691 | int seccomp_filter_set_add(Hashmap *filter, bool add, const SyscallFilterSet *set) { |
165a31c0 LP |
1692 | const char *i; |
1693 | int r; | |
1694 | ||
1695 | assert(set); | |
1696 | ||
1697 | NULSTR_FOREACH(i, set->value) { | |
1698 | ||
1699 | if (i[0] == '@') { | |
1700 | const SyscallFilterSet *more; | |
1701 | ||
1702 | more = syscall_filter_set_find(i); | |
1703 | if (!more) | |
1704 | return -ENXIO; | |
1705 | ||
165a31c0 LP |
1706 | r = seccomp_filter_set_add(filter, add, more); |
1707 | if (r < 0) | |
1708 | return r; | |
1709 | } else { | |
1710 | int id; | |
1711 | ||
1712 | id = seccomp_syscall_resolve_name(i); | |
ff217dc3 LP |
1713 | if (id == __NR_SCMP_ERROR) { |
1714 | log_debug("Couldn't resolve system call, ignoring: %s", i); | |
1715 | continue; | |
1716 | } | |
165a31c0 LP |
1717 | |
1718 | if (add) { | |
8cfa775f | 1719 | r = hashmap_put(filter, INT_TO_PTR(id + 1), INT_TO_PTR(-1)); |
165a31c0 LP |
1720 | if (r < 0) |
1721 | return r; | |
1722 | } else | |
8cfa775f | 1723 | (void) hashmap_remove(filter, INT_TO_PTR(id + 1)); |
165a31c0 LP |
1724 | } |
1725 | } | |
1726 | ||
1727 | return 0; | |
1728 | } | |
78e864e5 TM |
1729 | |
1730 | int seccomp_lock_personality(unsigned long personality) { | |
72eafe71 | 1731 | uint32_t arch; |
78e864e5 TM |
1732 | int r; |
1733 | ||
72eafe71 LP |
1734 | if (personality >= PERSONALITY_INVALID) |
1735 | return -EINVAL; | |
78e864e5 | 1736 | |
72eafe71 LP |
1737 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { |
1738 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
78e864e5 | 1739 | |
72eafe71 LP |
1740 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); |
1741 | if (r < 0) | |
1742 | return r; | |
1743 | ||
1744 | r = seccomp_rule_add_exact( | |
1745 | seccomp, | |
1746 | SCMP_ACT_ERRNO(EPERM), | |
1747 | SCMP_SYS(personality), | |
1748 | 1, | |
1749 | SCMP_A0(SCMP_CMP_NE, personality)); | |
448ac526 LP |
1750 | if (r < 0) { |
1751 | log_debug_errno(r, "Failed to add scheduler rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1752 | continue; | |
1753 | } | |
72eafe71 LP |
1754 | |
1755 | r = seccomp_load(seccomp); | |
1756 | if (IN_SET(r, -EPERM, -EACCES)) | |
1757 | return r; | |
1758 | if (r < 0) | |
1759 | log_debug_errno(r, "Failed to enable personality lock for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1760 | } | |
1761 | ||
1762 | return 0; | |
78e864e5 | 1763 | } |
aecd5ac6 TM |
1764 | |
1765 | int seccomp_protect_hostname(void) { | |
1766 | uint32_t arch; | |
1767 | int r; | |
1768 | ||
1769 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { | |
1770 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
1771 | ||
1772 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); | |
1773 | if (r < 0) | |
1774 | return r; | |
1775 | ||
1776 | r = seccomp_rule_add_exact( | |
1777 | seccomp, | |
1778 | SCMP_ACT_ERRNO(EPERM), | |
1779 | SCMP_SYS(sethostname), | |
1780 | 0); | |
9e6e543c LP |
1781 | if (r < 0) { |
1782 | log_debug_errno(r, "Failed to add sethostname() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
aecd5ac6 | 1783 | continue; |
9e6e543c | 1784 | } |
aecd5ac6 TM |
1785 | |
1786 | r = seccomp_rule_add_exact( | |
1787 | seccomp, | |
1788 | SCMP_ACT_ERRNO(EPERM), | |
1789 | SCMP_SYS(setdomainname), | |
1790 | 0); | |
9e6e543c LP |
1791 | if (r < 0) { |
1792 | log_debug_errno(r, "Failed to add setdomainname() rule for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
aecd5ac6 | 1793 | continue; |
9e6e543c | 1794 | } |
aecd5ac6 TM |
1795 | |
1796 | r = seccomp_load(seccomp); | |
1797 | if (IN_SET(r, -EPERM, -EACCES)) | |
1798 | return r; | |
1799 | if (r < 0) | |
1800 | log_debug_errno(r, "Failed to apply hostname restrictions for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1801 | } | |
1802 | ||
1803 | return 0; | |
1804 | } | |
3c27973b | 1805 | |
da4dc9a6 ZJS |
1806 | static int seccomp_restrict_sxid(scmp_filter_ctx seccomp, mode_t m) { |
1807 | /* Checks the mode_t parameter of the following system calls: | |
1808 | * | |
1809 | * → chmod() + fchmod() + fchmodat() | |
1810 | * → open() + creat() + openat() | |
1811 | * → mkdir() + mkdirat() | |
1812 | * → mknod() + mknodat() | |
1813 | * | |
1814 | * Returns error if *everything* failed, and 0 otherwise. | |
1815 | */ | |
1816 | int r = 0; | |
1817 | bool any = false; | |
1818 | ||
1819 | r = seccomp_rule_add_exact( | |
1820 | seccomp, | |
1821 | SCMP_ACT_ERRNO(EPERM), | |
1822 | SCMP_SYS(chmod), | |
1823 | 1, | |
1824 | SCMP_A1(SCMP_CMP_MASKED_EQ, m, m)); | |
1825 | if (r < 0) | |
1826 | log_debug_errno(r, "Failed to add filter for chmod: %m"); | |
1827 | else | |
1828 | any = true; | |
1829 | ||
1830 | r = seccomp_rule_add_exact( | |
1831 | seccomp, | |
1832 | SCMP_ACT_ERRNO(EPERM), | |
1833 | SCMP_SYS(fchmod), | |
1834 | 1, | |
1835 | SCMP_A1(SCMP_CMP_MASKED_EQ, m, m)); | |
1836 | if (r < 0) | |
1837 | log_debug_errno(r, "Failed to add filter for fchmod: %m"); | |
1838 | else | |
1839 | any = true; | |
1840 | ||
1841 | r = seccomp_rule_add_exact( | |
1842 | seccomp, | |
1843 | SCMP_ACT_ERRNO(EPERM), | |
1844 | SCMP_SYS(fchmodat), | |
1845 | 1, | |
1846 | SCMP_A2(SCMP_CMP_MASKED_EQ, m, m)); | |
1847 | if (r < 0) | |
1848 | log_debug_errno(r, "Failed to add filter for fchmodat: %m"); | |
1849 | else | |
1850 | any = true; | |
1851 | ||
1852 | r = seccomp_rule_add_exact( | |
1853 | seccomp, | |
1854 | SCMP_ACT_ERRNO(EPERM), | |
1855 | SCMP_SYS(mkdir), | |
1856 | 1, | |
1857 | SCMP_A1(SCMP_CMP_MASKED_EQ, m, m)); | |
1858 | if (r < 0) | |
1859 | log_debug_errno(r, "Failed to add filter for mkdir: %m"); | |
1860 | else | |
1861 | any = true; | |
1862 | ||
1863 | r = seccomp_rule_add_exact( | |
1864 | seccomp, | |
1865 | SCMP_ACT_ERRNO(EPERM), | |
1866 | SCMP_SYS(mkdirat), | |
1867 | 1, | |
1868 | SCMP_A2(SCMP_CMP_MASKED_EQ, m, m)); | |
1869 | if (r < 0) | |
1870 | log_debug_errno(r, "Failed to add filter for mkdirat: %m"); | |
1871 | else | |
1872 | any = true; | |
1873 | ||
1874 | r = seccomp_rule_add_exact( | |
1875 | seccomp, | |
1876 | SCMP_ACT_ERRNO(EPERM), | |
1877 | SCMP_SYS(mknod), | |
1878 | 1, | |
1879 | SCMP_A1(SCMP_CMP_MASKED_EQ, m, m)); | |
1880 | if (r < 0) | |
1881 | log_debug_errno(r, "Failed to add filter for mknod: %m"); | |
1882 | else | |
1883 | any = true; | |
1884 | ||
1885 | r = seccomp_rule_add_exact( | |
1886 | seccomp, | |
1887 | SCMP_ACT_ERRNO(EPERM), | |
1888 | SCMP_SYS(mknodat), | |
1889 | 1, | |
1890 | SCMP_A2(SCMP_CMP_MASKED_EQ, m, m)); | |
1891 | if (r < 0) | |
1892 | log_debug_errno(r, "Failed to add filter for mknodat: %m"); | |
1893 | else | |
1894 | any = true; | |
1895 | ||
1896 | #if SCMP_SYS(open) > 0 | |
1897 | r = seccomp_rule_add_exact( | |
1898 | seccomp, | |
1899 | SCMP_ACT_ERRNO(EPERM), | |
1900 | SCMP_SYS(open), | |
1901 | 2, | |
1902 | SCMP_A1(SCMP_CMP_MASKED_EQ, O_CREAT, O_CREAT), | |
1903 | SCMP_A2(SCMP_CMP_MASKED_EQ, m, m)); | |
1904 | if (r < 0) | |
1905 | log_debug_errno(r, "Failed to add filter for open: %m"); | |
1906 | else | |
1907 | any = true; | |
1908 | #endif | |
1909 | ||
1910 | r = seccomp_rule_add_exact( | |
1911 | seccomp, | |
1912 | SCMP_ACT_ERRNO(EPERM), | |
1913 | SCMP_SYS(openat), | |
1914 | 2, | |
1915 | SCMP_A2(SCMP_CMP_MASKED_EQ, O_CREAT, O_CREAT), | |
1916 | SCMP_A3(SCMP_CMP_MASKED_EQ, m, m)); | |
1917 | if (r < 0) | |
1918 | log_debug_errno(r, "Failed to add filter for openat: %m"); | |
1919 | else | |
1920 | any = true; | |
1921 | ||
1922 | r = seccomp_rule_add_exact( | |
1923 | seccomp, | |
1924 | SCMP_ACT_ERRNO(EPERM), | |
1925 | SCMP_SYS(creat), | |
1926 | 1, | |
1927 | SCMP_A1(SCMP_CMP_MASKED_EQ, m, m)); | |
1928 | if (r < 0) | |
1929 | log_debug_errno(r, "Failed to add filter for creat: %m"); | |
1930 | else | |
1931 | any = true; | |
1932 | ||
1933 | return any ? 0 : r; | |
1934 | } | |
1935 | ||
3c27973b LP |
1936 | int seccomp_restrict_suid_sgid(void) { |
1937 | uint32_t arch; | |
da4dc9a6 | 1938 | int r, k; |
3c27973b LP |
1939 | |
1940 | SECCOMP_FOREACH_LOCAL_ARCH(arch) { | |
1941 | _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL; | |
1942 | ||
1943 | r = seccomp_init_for_arch(&seccomp, arch, SCMP_ACT_ALLOW); | |
1944 | if (r < 0) | |
1945 | return r; | |
1946 | ||
da4dc9a6 ZJS |
1947 | r = seccomp_restrict_sxid(seccomp, S_ISUID); |
1948 | if (r < 0) | |
1949 | log_debug_errno(r, "Failed to add suid rule for architecture %s, ignoring: %m", seccomp_arch_to_string(arch)); | |
3c27973b | 1950 | |
da4dc9a6 ZJS |
1951 | k = seccomp_restrict_sxid(seccomp, S_ISGID); |
1952 | if (k < 0) | |
1953 | log_debug_errno(r, "Failed to add sgid rule for architecture %s, ignoring: %m", seccomp_arch_to_string(arch)); | |
3c27973b | 1954 | |
da4dc9a6 | 1955 | if (r < 0 && k < 0) |
3c27973b | 1956 | continue; |
3c27973b LP |
1957 | |
1958 | r = seccomp_load(seccomp); | |
1959 | if (IN_SET(r, -EPERM, -EACCES)) | |
1960 | return r; | |
1961 | if (r < 0) | |
1962 | log_debug_errno(r, "Failed to apply suid/sgid restrictions for architecture %s, skipping: %m", seccomp_arch_to_string(arch)); | |
1963 | } | |
1964 | ||
1965 | return 0; | |
1966 | } |