2 1a49166d 2021-01-23 op * Copyright (c) 2021 Omar Polo <op@omarpolo.com>
4 e29dbd72 2021-01-23 op * Permission to use, copy, modify, and distribute this software for any
5 e29dbd72 2021-01-23 op * purpose with or without fee is hereby granted, provided that the above
6 e29dbd72 2021-01-23 op * copyright notice and this permission notice appear in all copies.
8 e29dbd72 2021-01-23 op * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 e29dbd72 2021-01-23 op * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 e29dbd72 2021-01-23 op * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 e29dbd72 2021-01-23 op * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 e29dbd72 2021-01-23 op * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 e29dbd72 2021-01-23 op * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 e29dbd72 2021-01-23 op * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 dafb57b8 2021-01-15 op #include "gmid.h"
19 8bb8cf2a 2021-07-02 op #if DISABLE_SANDBOX
21 8bb8cf2a 2021-07-02 op #warning "Sandbox disabled! Please report issues upstream instead of disabling the sandbox."
24 8bb8cf2a 2021-07-02 op sandbox_server_process(void)
30 8bb8cf2a 2021-07-02 op sandbox_executor_process(void)
32 8bb8cf2a 2021-07-02 op log_notice(NULL, "Sandbox disabled! "
33 8bb8cf2a 2021-07-02 op "Please report issues upstream instead of disabling the sandbox.");
37 8bb8cf2a 2021-07-02 op sandbox_logger_process(void)
42 8bb8cf2a 2021-07-02 op #elif defined(__FreeBSD__)
44 dafb57b8 2021-01-15 op #include <sys/capsicum.h>
47 62e001b0 2021-03-20 op sandbox_server_process(void)
49 dafb57b8 2021-01-15 op if (cap_enter() == -1)
50 8e56d6ad 2021-02-11 op fatal("cap_enter");
54 62e001b0 2021-03-20 op sandbox_executor_process(void)
57 a8a1f439 2021-07-07 op * We cannot capsicum the executor process because it needs to
58 a8a1f439 2021-07-07 op * fork(2)+execve(2) cgi scripts
64 62e001b0 2021-03-20 op sandbox_logger_process(void)
66 62e001b0 2021-03-20 op if (cap_enter() == -1)
67 62e001b0 2021-03-20 op fatal("cap_enter");
70 dafb57b8 2021-01-15 op #elif defined(__linux__)
72 71b7eb2f 2021-01-17 op #include <sys/prctl.h>
73 71b7eb2f 2021-01-17 op #include <sys/syscall.h>
74 71b7eb2f 2021-01-17 op #include <sys/syscall.h>
75 71b7eb2f 2021-01-17 op #include <sys/types.h>
77 71b7eb2f 2021-01-17 op #include <linux/audit.h>
78 71b7eb2f 2021-01-17 op #include <linux/filter.h>
79 71b7eb2f 2021-01-17 op #include <linux/seccomp.h>
81 71b7eb2f 2021-01-17 op #include <errno.h>
82 3c0375e4 2021-01-20 op #include <fcntl.h>
83 71b7eb2f 2021-01-17 op #include <stddef.h>
84 71b7eb2f 2021-01-17 op #include <stdio.h>
85 71b7eb2f 2021-01-17 op #include <string.h>
87 3499ce5a 2021-09-19 op #if HAVE_LANDLOCK
88 3499ce5a 2021-09-19 op # include "landlock_shim.h"
91 137def5f 2021-07-02 op /* uncomment to enable debugging. ONLY FOR DEVELOPMENT */
92 137def5f 2021-07-02 op /* #define SC_DEBUG */
94 137def5f 2021-07-02 op #ifdef SC_DEBUG
95 137def5f 2021-07-02 op # define SC_FAIL SECCOMP_RET_TRAP
97 137def5f 2021-07-02 op # define SC_FAIL SECCOMP_RET_KILL
100 137def5f 2021-07-02 op #if (BYTE_ORDER == LITTLE_ENDIAN)
101 137def5f 2021-07-02 op # define SC_ARG_LO 0
102 137def5f 2021-07-02 op # define SC_ARG_HI sizeof(uint32_t)
103 137def5f 2021-07-02 op #elif (BYTE_ORDER == BIG_ENDIAN)
104 137def5f 2021-07-02 op # define SC_ARG_LO sizeof(uint32_t)
105 137def5f 2021-07-02 op # define SC_ARG_HI 0
107 137def5f 2021-07-02 op # error "Uknown endian"
110 137def5f 2021-07-02 op /* make the filter more readable */
111 137def5f 2021-07-02 op #define SC_ALLOW(nr) \
112 137def5f 2021-07-02 op BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, __NR_##nr, 0, 1), \
113 137def5f 2021-07-02 op BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW)
116 137def5f 2021-07-02 op * SC_ALLOW_ARG and the SECCOMP_AUDIT_ARCH below are courtesy of
117 137def5f 2021-07-02 op * https://roy.marples.name/git/dhcpcd/blob/HEAD:/src/privsep-linux.c
119 137def5f 2021-07-02 op #define SC_ALLOW_ARG(_nr, _arg, _val) \
120 137def5f 2021-07-02 op BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, (_nr), 0, 6), \
121 137def5f 2021-07-02 op BPF_STMT(BPF_LD + BPF_W + BPF_ABS, \
122 137def5f 2021-07-02 op offsetof(struct seccomp_data, args[(_arg)]) + SC_ARG_LO), \
123 137def5f 2021-07-02 op BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, \
124 137def5f 2021-07-02 op ((_val) & 0xffffffff), 0, 3), \
125 137def5f 2021-07-02 op BPF_STMT(BPF_LD + BPF_W + BPF_ABS, \
126 137def5f 2021-07-02 op offsetof(struct seccomp_data, args[(_arg)]) + SC_ARG_HI), \
127 137def5f 2021-07-02 op BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, \
128 137def5f 2021-07-02 op (((uint32_t)((uint64_t)(_val) >> 32)) & 0xffffffff), 0, 1), \
129 137def5f 2021-07-02 op BPF_STMT(BPF_RET + BPF_K, SECCOMP_RET_ALLOW), \
130 137def5f 2021-07-02 op BPF_STMT(BPF_LD + BPF_W + BPF_ABS, \
131 137def5f 2021-07-02 op offsetof(struct seccomp_data, nr))
134 137def5f 2021-07-02 op * I personally find this quite nutty. Why can a system header not
135 137def5f 2021-07-02 op * define a default for this?
137 71b7eb2f 2021-01-17 op #if defined(__i386__)
138 71b7eb2f 2021-01-17 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_I386
139 71b7eb2f 2021-01-17 op #elif defined(__x86_64__)
140 71b7eb2f 2021-01-17 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_X86_64
141 137def5f 2021-07-02 op #elif defined(__arc__)
142 137def5f 2021-07-02 op # if defined(__A7__)
143 137def5f 2021-07-02 op # if (BYTE_ORDER == LITTLE_ENDIAN)
144 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ARCOMPACT
146 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ARCOMPACTBE
148 137def5f 2021-07-02 op # elif defined(__HS__)
149 137def5f 2021-07-02 op # if (BYTE_ORDER == LITTLE_ENDIAN)
150 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ARCV2
152 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ARCV2BE
155 137def5f 2021-07-02 op # error "Platform does not support seccomp filter yet"
157 71b7eb2f 2021-01-17 op #elif defined(__arm__)
158 137def5f 2021-07-02 op # ifndef EM_ARM
159 137def5f 2021-07-02 op # define EM_ARM 40
161 137def5f 2021-07-02 op # if (BYTE_ORDER == LITTLE_ENDIAN)
162 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ARM
164 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ARMEB
166 71b7eb2f 2021-01-17 op #elif defined(__aarch64__)
167 71b7eb2f 2021-01-17 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_AARCH64
168 137def5f 2021-07-02 op #elif defined(__alpha__)
169 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ALPHA
170 137def5f 2021-07-02 op #elif defined(__hppa__)
171 137def5f 2021-07-02 op # if defined(__LP64__)
172 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_PARISC64
174 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_PARISC
176 137def5f 2021-07-02 op #elif defined(__ia64__)
177 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_IA64
178 137def5f 2021-07-02 op #elif defined(__microblaze__)
179 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_MICROBLAZE
180 137def5f 2021-07-02 op #elif defined(__m68k__)
181 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_M68K
182 71b7eb2f 2021-01-17 op #elif defined(__mips__)
183 137def5f 2021-07-02 op # if defined(__MIPSEL__)
184 137def5f 2021-07-02 op # if defined(__LP64__)
185 71b7eb2f 2021-01-17 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_MIPSEL64
187 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_MIPSEL
189 137def5f 2021-07-02 op # elif defined(__LP64__)
190 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_MIPS64
192 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_MIPS
194 137def5f 2021-07-02 op #elif defined(__nds32__)
195 137def5f 2021-07-02 op # if (BYTE_ORDER == LITTLE_ENDIAN)
196 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_NDS32
198 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_NDS32BE
200 137def5f 2021-07-02 op #elif defined(__nios2__)
201 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_NIOS2
202 137def5f 2021-07-02 op #elif defined(__or1k__)
203 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_OPENRISC
204 137def5f 2021-07-02 op #elif defined(__powerpc64__)
205 b24021d4 2021-07-03 op # if (BYTE_ORDER == LITTLE_ENDIAN)
206 b24021d4 2021-07-03 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_PPC64LE
208 b24021d4 2021-07-03 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_PPC64
210 137def5f 2021-07-02 op #elif defined(__powerpc__)
211 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_PPC
212 137def5f 2021-07-02 op #elif defined(__riscv)
213 137def5f 2021-07-02 op # if defined(__LP64__)
214 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_RISCV64
216 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_RISCV32
218 137def5f 2021-07-02 op #elif defined(__s390x__)
219 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_S390X
220 137def5f 2021-07-02 op #elif defined(__s390__)
221 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_S390
222 137def5f 2021-07-02 op #elif defined(__sh__)
223 137def5f 2021-07-02 op # if defined(__LP64__)
224 137def5f 2021-07-02 op # if (BYTE_ORDER == LITTLE_ENDIAN)
225 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_SHEL64
227 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_SH64
230 137def5f 2021-07-02 op # if (BYTE_ORDER == LITTLE_ENDIAN)
231 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_SHEL
233 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_SH
236 137def5f 2021-07-02 op #elif defined(__sparc__)
237 137def5f 2021-07-02 op # if defined(__arch64__)
238 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_SPARC64
240 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_SPARC
242 137def5f 2021-07-02 op #elif defined(__xtensa__)
243 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_XTENSA
245 71b7eb2f 2021-01-17 op # error "Platform does not support seccomp filter yet"
248 137def5f 2021-07-02 op static struct sock_filter filter[] = {
249 137def5f 2021-07-02 op /* load the *current* architecture */
250 137def5f 2021-07-02 op BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
251 137def5f 2021-07-02 op (offsetof(struct seccomp_data, arch))),
252 137def5f 2021-07-02 op /* ensure it's the same that we've been compiled on */
253 137def5f 2021-07-02 op BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K,
254 137def5f 2021-07-02 op SECCOMP_AUDIT_ARCH, 1, 0),
255 137def5f 2021-07-02 op /* if not, kill the program */
256 137def5f 2021-07-02 op BPF_STMT(BPF_RET | BPF_K, SC_FAIL),
258 137def5f 2021-07-02 op /* load the syscall number */
259 137def5f 2021-07-02 op BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
260 137def5f 2021-07-02 op (offsetof(struct seccomp_data, nr))),
262 137def5f 2021-07-02 op #ifdef __NR_accept
263 137def5f 2021-07-02 op SC_ALLOW(accept),
265 137def5f 2021-07-02 op #ifdef __NR_accept4
266 137def5f 2021-07-02 op SC_ALLOW(accept4),
268 137def5f 2021-07-02 op #ifdef __NR_brk
269 137def5f 2021-07-02 op SC_ALLOW(brk),
271 137def5f 2021-07-02 op #ifdef __NR_clock_gettime
272 137def5f 2021-07-02 op SC_ALLOW(clock_gettime),
274 137def5f 2021-07-02 op #if defined(__x86_64__) && defined(__ILP32__) && defined(__X32_SYSCALL_BIT)
275 137def5f 2021-07-02 op SECCOMP_ALLOW(__NR_clock_gettime & ~__X32_SYSCALL_BIT),
277 137def5f 2021-07-02 op #ifdef __NR_clock_gettime64
278 137def5f 2021-07-02 op SC_ALLOW(clock_gettime64),
280 137def5f 2021-07-02 op #ifdef __NR_close
281 137def5f 2021-07-02 op SC_ALLOW(close),
283 137def5f 2021-07-02 op #ifdef __NR_epoll_ctl
284 137def5f 2021-07-02 op SC_ALLOW(epoll_ctl),
286 137def5f 2021-07-02 op #ifdef __NR_epoll_pwait
287 137def5f 2021-07-02 op SC_ALLOW(epoll_pwait),
289 137def5f 2021-07-02 op #ifdef __NR_epoll_wait
290 137def5f 2021-07-02 op SC_ALLOW(epoll_wait),
292 137def5f 2021-07-02 op #ifdef __NR_exit
293 137def5f 2021-07-02 op SC_ALLOW(exit),
295 137def5f 2021-07-02 op #ifdef __NR_exit_group
296 137def5f 2021-07-02 op SC_ALLOW(exit_group),
298 137def5f 2021-07-02 op #ifdef __NR_fcntl
299 137def5f 2021-07-02 op SC_ALLOW(fcntl),
301 137def5f 2021-07-02 op #ifdef __NR_fcntl64
302 137def5f 2021-07-02 op SC_ALLOW(fcntl64),
304 137def5f 2021-07-02 op #ifdef __NR_fstat
305 137def5f 2021-07-02 op SC_ALLOW(fstat),
307 21f7d246 2021-07-23 op #ifdef __NR_fstat64
308 21f7d246 2021-07-23 op SC_ALLOW(fstat64),
310 137def5f 2021-07-02 op #ifdef __NR_getdents64
311 137def5f 2021-07-02 op SC_ALLOW(getdents64),
313 137def5f 2021-07-02 op #ifdef __NR_getpid
314 137def5f 2021-07-02 op SC_ALLOW(getpid),
316 137def5f 2021-07-02 op #ifdef __NR_getrandom
317 137def5f 2021-07-02 op SC_ALLOW(getrandom),
319 137def5f 2021-07-02 op #ifdef __NR_gettimeofday
320 137def5f 2021-07-02 op SC_ALLOW(gettimeofday),
322 137def5f 2021-07-02 op #ifdef __NR_ioctl
323 137def5f 2021-07-02 op /* allow ioctl only on fd 1, glibc doing stuff? */
324 137def5f 2021-07-02 op SC_ALLOW_ARG(__NR_ioctl, 0, 1),
326 137def5f 2021-07-02 op #ifdef __NR_lseek
327 137def5f 2021-07-02 op SC_ALLOW(lseek),
329 137def5f 2021-07-02 op #ifdef __NR_madvise
330 137def5f 2021-07-02 op SC_ALLOW(madvise),
332 137def5f 2021-07-02 op #ifdef __NR_mmap
333 137def5f 2021-07-02 op SC_ALLOW(mmap),
335 137def5f 2021-07-02 op #ifdef __NR_mmap2
336 137def5f 2021-07-02 op SC_ALLOW(mmap2),
338 137def5f 2021-07-02 op #ifdef __NR_munmap
339 137def5f 2021-07-02 op SC_ALLOW(munmap),
341 137def5f 2021-07-02 op #ifdef __NR_newfstatat
342 137def5f 2021-07-02 op SC_ALLOW(newfstatat),
344 137def5f 2021-07-02 op #ifdef __NR_oldfstat
345 137def5f 2021-07-02 op SC_ALLOW(oldfstat),
347 137def5f 2021-07-02 op #ifdef __NR_openat
348 137def5f 2021-07-02 op SC_ALLOW(openat),
350 137def5f 2021-07-02 op #ifdef __NR_prlimit64
351 137def5f 2021-07-02 op SC_ALLOW(prlimit64),
353 137def5f 2021-07-02 op #ifdef __NR_read
354 137def5f 2021-07-02 op SC_ALLOW(read),
356 137def5f 2021-07-02 op #ifdef __NR_recvmsg
357 137def5f 2021-07-02 op SC_ALLOW(recvmsg),
359 a8e1e8d7 2021-07-23 op #ifdef __NR_readv
360 a8e1e8d7 2021-07-23 op SC_ALLOW(readv),
362 137def5f 2021-07-02 op #ifdef __NR_rt_sigaction
363 137def5f 2021-07-02 op SC_ALLOW(rt_sigaction),
365 137def5f 2021-07-02 op #ifdef __NR_rt_sigreturn
366 137def5f 2021-07-02 op SC_ALLOW(rt_sigreturn),
368 137def5f 2021-07-02 op #ifdef __NR_sendmsg
369 137def5f 2021-07-02 op SC_ALLOW(sendmsg),
371 137def5f 2021-07-02 op #ifdef __NR_statx
372 137def5f 2021-07-02 op SC_ALLOW(statx),
374 137def5f 2021-07-02 op #ifdef __NR_write
375 137def5f 2021-07-02 op SC_ALLOW(write),
377 137def5f 2021-07-02 op #ifdef __NR_writev
378 137def5f 2021-07-02 op SC_ALLOW(writev),
381 4aa1dd55 2021-07-03 op /* disallow everything else */
382 137def5f 2021-07-02 op BPF_STMT(BPF_RET | BPF_K, SC_FAIL),
385 71b7eb2f 2021-01-17 op #ifdef SC_DEBUG
387 71b7eb2f 2021-01-17 op #include <signal.h>
388 71b7eb2f 2021-01-17 op #include <unistd.h>
391 71b7eb2f 2021-01-17 op sandbox_seccomp_violation(int signum, siginfo_t *info, void *ctx)
393 71b7eb2f 2021-01-17 op (void)signum;
396 71b7eb2f 2021-01-17 op fprintf(stderr, "%s: unexpected system call (arch:0x%x,syscall:%d @ %p)\n",
397 71b7eb2f 2021-01-17 op __func__, info->si_arch, info->si_syscall, info->si_call_addr);
402 71b7eb2f 2021-01-17 op sandbox_seccomp_catch_sigsys(void)
404 71b7eb2f 2021-01-17 op struct sigaction act;
405 71b7eb2f 2021-01-17 op sigset_t mask;
407 71b7eb2f 2021-01-17 op memset(&act, 0, sizeof(act));
408 71b7eb2f 2021-01-17 op sigemptyset(&mask);
409 71b7eb2f 2021-01-17 op sigaddset(&mask, SIGSYS);
411 71b7eb2f 2021-01-17 op act.sa_sigaction = &sandbox_seccomp_violation;
412 71b7eb2f 2021-01-17 op act.sa_flags = SA_SIGINFO;
413 8e56d6ad 2021-02-11 op if (sigaction(SIGSYS, &act, NULL) == -1)
414 8e56d6ad 2021-02-11 op fatal("%s: sigaction(SIGSYS): %s",
415 71b7eb2f 2021-01-17 op __func__, strerror(errno));
417 8e56d6ad 2021-02-11 op if (sigprocmask(SIG_UNBLOCK, &mask, NULL) == -1)
418 8e56d6ad 2021-02-11 op fatal("%s: sigprocmask(SIGSYS): %s\n",
419 71b7eb2f 2021-01-17 op __func__, strerror(errno));
421 71b7eb2f 2021-01-17 op #endif /* SC_DEBUG */
423 3499ce5a 2021-09-19 op #if HAVE_LANDLOCK
424 0ea22af2 2021-09-19 op static inline int
425 0ea22af2 2021-09-19 op gmid_create_landlock_rs(struct landlock_ruleset_attr *attr, size_t len,
430 0ea22af2 2021-09-19 op fd = landlock_create_ruleset(attr, len, 0);
431 0ea22af2 2021-09-19 op if (fd == -1) {
432 0ea22af2 2021-09-19 op switch (errno) {
434 0ea22af2 2021-09-19 op fatal("%s: failed to create ruleset. "
435 0ea22af2 2021-09-19 op "Landlock doesn't seem to be supported by the "
436 0ea22af2 2021-09-19 op "current kernel.", __func__);
437 0ea22af2 2021-09-19 op case EOPNOTSUPP:
438 0ea22af2 2021-09-19 op log_warn(NULL, "%s: failed to create ruleset. "
439 0ea22af2 2021-09-19 op "Landlock seems to be currently disabled; "
440 0ea22af2 2021-09-19 op "continuing without it.", __func__);
443 0ea22af2 2021-09-19 op fatal("%s: failed to create ruleset: %s",
444 0ea22af2 2021-09-19 op __func__, strerror(errno));
452 3499ce5a 2021-09-19 op server_landlock(void)
455 3499ce5a 2021-09-19 op struct vhost *h;
456 3499ce5a 2021-09-19 op struct location *l;
459 3499ce5a 2021-09-19 op * These are all the actions that we want to either allow or
460 3499ce5a 2021-09-19 op * disallow. Things like LANDLOCK_ACCESS_FS_EXECUTE are
461 3499ce5a 2021-09-19 op * omitted because are already handled by seccomp.
463 3499ce5a 2021-09-19 op struct landlock_ruleset_attr ruleset_attr = {
464 3499ce5a 2021-09-19 op .handled_access_fs = LANDLOCK_ACCESS_FS_WRITE_FILE |
465 3499ce5a 2021-09-19 op LANDLOCK_ACCESS_FS_READ_FILE |
466 3499ce5a 2021-09-19 op LANDLOCK_ACCESS_FS_READ_DIR |
467 3499ce5a 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_CHAR |
468 3499ce5a 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_DIR |
469 3499ce5a 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_REG |
470 3499ce5a 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_SOCK |
471 3499ce5a 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_FIFO |
472 3499ce5a 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_BLOCK |
473 3499ce5a 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_SYM,
477 3499ce5a 2021-09-19 op * These are all the actions allowed for the root directories
478 3499ce5a 2021-09-19 op * of the vhosts. All the other rules mentioned in
479 3499ce5a 2021-09-19 op * ruleset_attr and omitted here are implicitly disallowed.
481 3499ce5a 2021-09-19 op struct landlock_path_beneath_attr path_beneath = {
482 3499ce5a 2021-09-19 op .allowed_access = LANDLOCK_ACCESS_FS_READ_FILE |
483 3499ce5a 2021-09-19 op LANDLOCK_ACCESS_FS_READ_DIR,
486 0ea22af2 2021-09-19 op fd = gmid_create_landlock_rs(&ruleset_attr, sizeof(ruleset_attr), 0);
487 0ea22af2 2021-09-19 op if (fd == -1)
490 3499ce5a 2021-09-19 op TAILQ_FOREACH(h, &hosts, vhosts) {
491 3499ce5a 2021-09-19 op TAILQ_FOREACH(l, &h->locations, locations) {
492 3499ce5a 2021-09-19 op if (l->dir == NULL)
495 3499ce5a 2021-09-19 op path_beneath.parent_fd = open(l->dir, O_PATH);
496 3499ce5a 2021-09-19 op if (path_beneath.parent_fd == -1)
497 3499ce5a 2021-09-19 op fatal("%s: can't open %s for landlock: %s",
498 3499ce5a 2021-09-19 op __func__, l->dir, strerror(errno));
500 3499ce5a 2021-09-19 op err = landlock_add_rule(fd, LANDLOCK_RULE_PATH_BENEATH,
501 3499ce5a 2021-09-19 op &path_beneath, 0);
503 3499ce5a 2021-09-19 op fatal("%s: landlock_add_rule(%s) failed: %s",
504 3499ce5a 2021-09-19 op __func__, l->dir, strerror(errno));
506 3499ce5a 2021-09-19 op close(path_beneath.parent_fd);
514 b0be0653 2021-09-19 op logger_landlock(void)
519 b0be0653 2021-09-19 op * These are all the possible actions. The logger receives
520 b0be0653 2021-09-19 op * files descriptor so it doesn't need *ANY* fs access. It's
521 b0be0653 2021-09-19 op * easier to remove FS access than come up with a seccomp
524 b0be0653 2021-09-19 op struct landlock_ruleset_attr ruleset_attr = {
525 b0be0653 2021-09-19 op .handled_access_fs = LANDLOCK_ACCESS_FS_EXECUTE |
526 b0be0653 2021-09-19 op LANDLOCK_ACCESS_FS_WRITE_FILE |
527 b0be0653 2021-09-19 op LANDLOCK_ACCESS_FS_READ_FILE |
528 b0be0653 2021-09-19 op LANDLOCK_ACCESS_FS_READ_DIR |
529 b0be0653 2021-09-19 op LANDLOCK_ACCESS_FS_REMOVE_DIR |
530 b0be0653 2021-09-19 op LANDLOCK_ACCESS_FS_REMOVE_FILE |
531 b0be0653 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_CHAR |
532 b0be0653 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_DIR |
533 b0be0653 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_REG |
534 b0be0653 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_SOCK |
535 b0be0653 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_FIFO |
536 b0be0653 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_BLOCK |
537 b0be0653 2021-09-19 op LANDLOCK_ACCESS_FS_MAKE_SYM,
541 b0be0653 2021-09-19 op * Disallow every action.
543 b0be0653 2021-09-19 op struct landlock_path_beneath_attr path_beneath = {
544 b0be0653 2021-09-19 op .allowed_access = 0,
547 b0be0653 2021-09-19 op fd = gmid_create_landlock_rs(&ruleset_attr, sizeof(ruleset_attr), 0);
548 b0be0653 2021-09-19 op if (fd == -1)
551 b0be0653 2021-09-19 op path_beneath.parent_fd = open("/", O_PATH);
552 b0be0653 2021-09-19 op if (path_beneath.parent_fd == -1)
553 b0be0653 2021-09-19 op fatal("%s: can't open / for landlock: %s",
554 b0be0653 2021-09-19 op __func__, strerror(errno));
556 b0be0653 2021-09-19 op err = landlock_add_rule(fd, LANDLOCK_RULE_PATH_BENEATH,
557 b0be0653 2021-09-19 op &path_beneath, 0);
559 b0be0653 2021-09-19 op fatal("%s: landlock_add_rule(/) failed: %s",
560 b0be0653 2021-09-19 op __func__, strerror(errno));
561 b0be0653 2021-09-19 op close(path_beneath.parent_fd);
568 62e001b0 2021-03-20 op sandbox_server_process(void)
571 71b7eb2f 2021-01-17 op struct sock_fprog prog = {
572 71b7eb2f 2021-01-17 op .len = (unsigned short) (sizeof(filter) / sizeof(filter[0])),
573 71b7eb2f 2021-01-17 op .filter = filter,
576 71b7eb2f 2021-01-17 op #ifdef SC_DEBUG
577 71b7eb2f 2021-01-17 op sandbox_seccomp_catch_sigsys();
580 3499ce5a 2021-09-19 op #if HAVE_LANDLOCK
581 3499ce5a 2021-09-19 op log_warn(NULL, "loading landlock...");
582 3499ce5a 2021-09-19 op fd = server_landlock();
584 3499ce5a 2021-09-19 op (void)fd; /* avoid unused var warning */
587 8e56d6ad 2021-02-11 op if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) == -1)
588 8e56d6ad 2021-02-11 op fatal("%s: prctl(PR_SET_NO_NEW_PRIVS): %s",
589 71b7eb2f 2021-01-17 op __func__, strerror(errno));
591 3499ce5a 2021-09-19 op #if HAVE_LANDLOCK
592 3499ce5a 2021-09-19 op if (fd != -1) {
593 3499ce5a 2021-09-19 op if (landlock_restrict_self(fd, 0))
594 3499ce5a 2021-09-19 op fatal("%s: landlock_restrict_self: %s",
595 3499ce5a 2021-09-19 op __func__, strerror(errno));
600 8e56d6ad 2021-02-11 op if (prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog) == -1)
601 8e56d6ad 2021-02-11 op fatal("%s: prctl(PR_SET_SECCOMP): %s\n",
602 71b7eb2f 2021-01-17 op __func__, strerror(errno));
606 62e001b0 2021-03-20 op sandbox_executor_process(void)
609 a8a1f439 2021-07-07 op * We cannot use seccomp for the executor process because we
610 62e001b0 2021-03-20 op * don't know what the child will do. Also, our filter will
611 62e001b0 2021-03-20 op * be inherited so the child cannot set its own seccomp
618 62e001b0 2021-03-20 op sandbox_logger_process(void)
621 b0be0653 2021-09-19 op * Here we could use a seccomp filter to allow only recvfd,
622 b0be0653 2021-09-19 op * write/writev and memory allocations, but syslog is a beast
623 b0be0653 2021-09-19 op * and I don't know what syscalls it could end up doing.
624 b0be0653 2021-09-19 op * Landlock is a simpler beast, use it to disallow any file
625 b0be0653 2021-09-19 op * sytsem access.
628 b0be0653 2021-09-19 op #if HAVE_LANDLOCK
631 b0be0653 2021-09-19 op if ((fd = logger_landlock()) == -1)
634 b0be0653 2021-09-19 op if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) == -1)
635 b0be0653 2021-09-19 op fatal("%s: prctl(PR_SET_NO_NEW_PRIVS): %s",
636 b0be0653 2021-09-19 op __func__, strerror(errno));
638 b0be0653 2021-09-19 op if (landlock_restrict_self(fd, 0))
639 b0be0653 2021-09-19 op fatal("%s: landlock_restrict_self: %s"
640 b0be0653 2021-09-19 op __func__, strerror(errno));
648 dafb57b8 2021-01-15 op #elif defined(__OpenBSD__)
650 dafb57b8 2021-01-15 op #include <unistd.h>
653 62e001b0 2021-03-20 op sandbox_server_process(void)
655 fdea6aa0 2021-04-30 op struct vhost *h;
656 fdea6aa0 2021-04-30 op struct location *l;
658 b8e64ccd 2021-03-31 op TAILQ_FOREACH(h, &hosts, vhosts) {
659 fdea6aa0 2021-04-30 op TAILQ_FOREACH(l, &h->locations, locations) {
660 fdea6aa0 2021-04-30 op if (l->dir == NULL)
663 fdea6aa0 2021-04-30 op if (unveil(l->dir, "r") == -1)
664 fdea6aa0 2021-04-30 op fatal("unveil %s for domain %s",
670 881a9dd9 2021-01-16 op if (pledge("stdio recvfd rpath inet", NULL) == -1)
671 8e56d6ad 2021-02-11 op fatal("pledge");
675 62e001b0 2021-03-20 op sandbox_executor_process(void)
677 b8e64ccd 2021-03-31 op struct vhost *h;
678 fdea6aa0 2021-04-30 op struct location *l;
679 8ad1c570 2021-05-09 op struct fcgi *f;
682 b8e64ccd 2021-03-31 op TAILQ_FOREACH(h, &hosts, vhosts) {
683 fdea6aa0 2021-04-30 op TAILQ_FOREACH(l, &h->locations, locations) {
684 fdea6aa0 2021-04-30 op if (l->dir == NULL)
687 a5d822e5 2021-07-09 op /* r so we can chdir into the directory */
688 fdea6aa0 2021-04-30 op if (unveil(l->dir, "rx") == -1)
689 fdea6aa0 2021-04-30 op fatal("unveil %s for domain %s",
690 fdea6aa0 2021-04-30 op l->dir, h->domain);
694 8ad1c570 2021-05-09 op for (i = 0; i < FCGI_MAX; i++) {
695 8ad1c570 2021-05-09 op f = &fcgi[i];
696 8ad1c570 2021-05-09 op if (f->path != NULL) {
697 8ad1c570 2021-05-09 op if (unveil(f->path, "rw") == -1)
698 8ad1c570 2021-05-09 op fatal("unveil %s", f->path);
701 8ad1c570 2021-05-09 op if (f->prog != NULL) {
702 8ad1c570 2021-05-09 op if (unveil(f->prog, "rx") == -1)
703 8ad1c570 2021-05-09 op fatal("unveil %s", f->prog);
708 8ad1c570 2021-05-09 op * rpath: to chdir into the correct directory
709 8ad1c570 2021-05-09 op * proc exec: CGI
710 8ad1c570 2021-05-09 op * dns inet unix: FastCGI
712 8ad1c570 2021-05-09 op if (pledge("stdio rpath sendfd proc exec dns inet unix", NULL))
713 62e001b0 2021-03-20 op err(1, "pledge");
717 62e001b0 2021-03-20 op sandbox_logger_process(void)
719 e952c505 2021-06-15 op if (pledge("stdio recvfd", NULL) == -1)
720 62e001b0 2021-03-20 op err(1, "pledge");
725 62e001b0 2021-03-20 op #warning "No sandbox method known for this OS"
728 62e001b0 2021-03-20 op sandbox_server_process(void)
734 62e001b0 2021-03-20 op sandbox_executor_process(void)
736 2a911637 2021-02-11 op log_notice(NULL, "no sandbox method known for this OS");
740 62e001b0 2021-03-20 op sandbox_logger_process(void)