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 76000995 2022-09-06 op sandbox_server_process(int can_open_sockets)
30 8bb8cf2a 2021-07-02 op sandbox_logger_process(void)
35 8bb8cf2a 2021-07-02 op #elif defined(__FreeBSD__)
37 dafb57b8 2021-01-15 op #include <sys/capsicum.h>
40 76000995 2022-09-06 op sandbox_server_process(int can_open_sockets)
42 76000995 2022-09-06 op /* can't capsicum if fastcgi or proxying are used. */
43 76000995 2022-09-06 op if (can_open_sockets)
46 dafb57b8 2021-01-15 op if (cap_enter() == -1)
47 8e56d6ad 2021-02-11 op fatal("cap_enter");
51 62e001b0 2021-03-20 op sandbox_logger_process(void)
53 62e001b0 2021-03-20 op if (cap_enter() == -1)
54 62e001b0 2021-03-20 op fatal("cap_enter");
57 dafb57b8 2021-01-15 op #elif defined(__linux__)
59 0c66b6ad 2021-09-26 op #include <sys/ioctl.h>
60 71b7eb2f 2021-01-17 op #include <sys/prctl.h>
61 71b7eb2f 2021-01-17 op #include <sys/syscall.h>
62 71b7eb2f 2021-01-17 op #include <sys/syscall.h>
63 71b7eb2f 2021-01-17 op #include <sys/types.h>
65 71b7eb2f 2021-01-17 op #include <linux/audit.h>
66 71b7eb2f 2021-01-17 op #include <linux/filter.h>
67 71b7eb2f 2021-01-17 op #include <linux/seccomp.h>
69 71b7eb2f 2021-01-17 op #include <errno.h>
70 3c0375e4 2021-01-20 op #include <fcntl.h>
71 71b7eb2f 2021-01-17 op #include <stddef.h>
72 71b7eb2f 2021-01-17 op #include <stdio.h>
73 71b7eb2f 2021-01-17 op #include <string.h>
75 3499ce5a 2021-09-19 op #if HAVE_LANDLOCK
76 3499ce5a 2021-09-19 op # include "landlock_shim.h"
79 137def5f 2021-07-02 op /* uncomment to enable debugging. ONLY FOR DEVELOPMENT */
80 137def5f 2021-07-02 op /* #define SC_DEBUG */
82 137def5f 2021-07-02 op #ifdef SC_DEBUG
83 137def5f 2021-07-02 op # define SC_FAIL SECCOMP_RET_TRAP
85 137def5f 2021-07-02 op # define SC_FAIL SECCOMP_RET_KILL
88 137def5f 2021-07-02 op #if (BYTE_ORDER == LITTLE_ENDIAN)
89 137def5f 2021-07-02 op # define SC_ARG_LO 0
90 137def5f 2021-07-02 op # define SC_ARG_HI sizeof(uint32_t)
91 137def5f 2021-07-02 op #elif (BYTE_ORDER == BIG_ENDIAN)
92 137def5f 2021-07-02 op # define SC_ARG_LO sizeof(uint32_t)
93 137def5f 2021-07-02 op # define SC_ARG_HI 0
95 137def5f 2021-07-02 op # error "Uknown endian"
98 137def5f 2021-07-02 op /* make the filter more readable */
99 137def5f 2021-07-02 op #define SC_ALLOW(nr) \
100 137def5f 2021-07-02 op BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, __NR_##nr, 0, 1), \
101 137def5f 2021-07-02 op BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW)
104 137def5f 2021-07-02 op * SC_ALLOW_ARG and the SECCOMP_AUDIT_ARCH below are courtesy of
105 137def5f 2021-07-02 op * https://roy.marples.name/git/dhcpcd/blob/HEAD:/src/privsep-linux.c
107 137def5f 2021-07-02 op #define SC_ALLOW_ARG(_nr, _arg, _val) \
108 137def5f 2021-07-02 op BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, (_nr), 0, 6), \
109 137def5f 2021-07-02 op BPF_STMT(BPF_LD + BPF_W + BPF_ABS, \
110 137def5f 2021-07-02 op offsetof(struct seccomp_data, args[(_arg)]) + SC_ARG_LO), \
111 137def5f 2021-07-02 op BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, \
112 137def5f 2021-07-02 op ((_val) & 0xffffffff), 0, 3), \
113 137def5f 2021-07-02 op BPF_STMT(BPF_LD + BPF_W + BPF_ABS, \
114 137def5f 2021-07-02 op offsetof(struct seccomp_data, args[(_arg)]) + SC_ARG_HI), \
115 137def5f 2021-07-02 op BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, \
116 137def5f 2021-07-02 op (((uint32_t)((uint64_t)(_val) >> 32)) & 0xffffffff), 0, 1), \
117 137def5f 2021-07-02 op BPF_STMT(BPF_RET + BPF_K, SECCOMP_RET_ALLOW), \
118 137def5f 2021-07-02 op BPF_STMT(BPF_LD + BPF_W + BPF_ABS, \
119 137def5f 2021-07-02 op offsetof(struct seccomp_data, nr))
122 137def5f 2021-07-02 op * I personally find this quite nutty. Why can a system header not
123 137def5f 2021-07-02 op * define a default for this?
125 71b7eb2f 2021-01-17 op #if defined(__i386__)
126 71b7eb2f 2021-01-17 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_I386
127 71b7eb2f 2021-01-17 op #elif defined(__x86_64__)
128 71b7eb2f 2021-01-17 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_X86_64
129 137def5f 2021-07-02 op #elif defined(__arc__)
130 137def5f 2021-07-02 op # if defined(__A7__)
131 137def5f 2021-07-02 op # if (BYTE_ORDER == LITTLE_ENDIAN)
132 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ARCOMPACT
134 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ARCOMPACTBE
136 137def5f 2021-07-02 op # elif defined(__HS__)
137 137def5f 2021-07-02 op # if (BYTE_ORDER == LITTLE_ENDIAN)
138 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ARCV2
140 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ARCV2BE
143 137def5f 2021-07-02 op # error "Platform does not support seccomp filter yet"
145 71b7eb2f 2021-01-17 op #elif defined(__arm__)
146 137def5f 2021-07-02 op # ifndef EM_ARM
147 137def5f 2021-07-02 op # define EM_ARM 40
149 137def5f 2021-07-02 op # if (BYTE_ORDER == LITTLE_ENDIAN)
150 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ARM
152 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ARMEB
154 71b7eb2f 2021-01-17 op #elif defined(__aarch64__)
155 71b7eb2f 2021-01-17 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_AARCH64
156 137def5f 2021-07-02 op #elif defined(__alpha__)
157 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_ALPHA
158 137def5f 2021-07-02 op #elif defined(__hppa__)
159 137def5f 2021-07-02 op # if defined(__LP64__)
160 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_PARISC64
162 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_PARISC
164 137def5f 2021-07-02 op #elif defined(__ia64__)
165 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_IA64
166 137def5f 2021-07-02 op #elif defined(__microblaze__)
167 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_MICROBLAZE
168 137def5f 2021-07-02 op #elif defined(__m68k__)
169 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_M68K
170 71b7eb2f 2021-01-17 op #elif defined(__mips__)
171 137def5f 2021-07-02 op # if defined(__MIPSEL__)
172 137def5f 2021-07-02 op # if defined(__LP64__)
173 71b7eb2f 2021-01-17 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_MIPSEL64
175 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_MIPSEL
177 137def5f 2021-07-02 op # elif defined(__LP64__)
178 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_MIPS64
180 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_MIPS
182 137def5f 2021-07-02 op #elif defined(__nds32__)
183 137def5f 2021-07-02 op # if (BYTE_ORDER == LITTLE_ENDIAN)
184 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_NDS32
186 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_NDS32BE
188 137def5f 2021-07-02 op #elif defined(__nios2__)
189 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_NIOS2
190 137def5f 2021-07-02 op #elif defined(__or1k__)
191 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_OPENRISC
192 137def5f 2021-07-02 op #elif defined(__powerpc64__)
193 b24021d4 2021-07-03 op # if (BYTE_ORDER == LITTLE_ENDIAN)
194 b24021d4 2021-07-03 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_PPC64LE
196 b24021d4 2021-07-03 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_PPC64
198 137def5f 2021-07-02 op #elif defined(__powerpc__)
199 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_PPC
200 137def5f 2021-07-02 op #elif defined(__riscv)
201 137def5f 2021-07-02 op # if defined(__LP64__)
202 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_RISCV64
204 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_RISCV32
206 137def5f 2021-07-02 op #elif defined(__s390x__)
207 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_S390X
208 137def5f 2021-07-02 op #elif defined(__s390__)
209 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_S390
210 137def5f 2021-07-02 op #elif defined(__sh__)
211 137def5f 2021-07-02 op # if defined(__LP64__)
212 137def5f 2021-07-02 op # if (BYTE_ORDER == LITTLE_ENDIAN)
213 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_SHEL64
215 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_SH64
218 137def5f 2021-07-02 op # if (BYTE_ORDER == LITTLE_ENDIAN)
219 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_SHEL
221 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_SH
224 137def5f 2021-07-02 op #elif defined(__sparc__)
225 137def5f 2021-07-02 op # if defined(__arch64__)
226 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_SPARC64
228 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_SPARC
230 137def5f 2021-07-02 op #elif defined(__xtensa__)
231 137def5f 2021-07-02 op # define SECCOMP_AUDIT_ARCH AUDIT_ARCH_XTENSA
233 71b7eb2f 2021-01-17 op # error "Platform does not support seccomp filter yet"
236 e5d82d94 2022-03-19 op static const struct sock_filter filter[] = {
237 137def5f 2021-07-02 op /* load the *current* architecture */
238 137def5f 2021-07-02 op BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
239 137def5f 2021-07-02 op (offsetof(struct seccomp_data, arch))),
240 137def5f 2021-07-02 op /* ensure it's the same that we've been compiled on */
241 137def5f 2021-07-02 op BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K,
242 137def5f 2021-07-02 op SECCOMP_AUDIT_ARCH, 1, 0),
243 137def5f 2021-07-02 op /* if not, kill the program */
244 137def5f 2021-07-02 op BPF_STMT(BPF_RET | BPF_K, SC_FAIL),
246 137def5f 2021-07-02 op /* load the syscall number */
247 137def5f 2021-07-02 op BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
248 137def5f 2021-07-02 op (offsetof(struct seccomp_data, nr))),
250 137def5f 2021-07-02 op #ifdef __NR_accept
251 137def5f 2021-07-02 op SC_ALLOW(accept),
253 137def5f 2021-07-02 op #ifdef __NR_accept4
254 137def5f 2021-07-02 op SC_ALLOW(accept4),
256 137def5f 2021-07-02 op #ifdef __NR_brk
257 137def5f 2021-07-02 op SC_ALLOW(brk),
259 137def5f 2021-07-02 op #ifdef __NR_clock_gettime
260 137def5f 2021-07-02 op SC_ALLOW(clock_gettime),
262 137def5f 2021-07-02 op #if defined(__x86_64__) && defined(__ILP32__) && defined(__X32_SYSCALL_BIT)
263 137def5f 2021-07-02 op SECCOMP_ALLOW(__NR_clock_gettime & ~__X32_SYSCALL_BIT),
265 137def5f 2021-07-02 op #ifdef __NR_clock_gettime64
266 137def5f 2021-07-02 op SC_ALLOW(clock_gettime64),
268 137def5f 2021-07-02 op #ifdef __NR_close
269 137def5f 2021-07-02 op SC_ALLOW(close),
271 137def5f 2021-07-02 op #ifdef __NR_epoll_ctl
272 137def5f 2021-07-02 op SC_ALLOW(epoll_ctl),
274 137def5f 2021-07-02 op #ifdef __NR_epoll_pwait
275 137def5f 2021-07-02 op SC_ALLOW(epoll_pwait),
277 137def5f 2021-07-02 op #ifdef __NR_epoll_wait
278 137def5f 2021-07-02 op SC_ALLOW(epoll_wait),
280 137def5f 2021-07-02 op #ifdef __NR_exit
281 137def5f 2021-07-02 op SC_ALLOW(exit),
283 137def5f 2021-07-02 op #ifdef __NR_exit_group
284 137def5f 2021-07-02 op SC_ALLOW(exit_group),
286 137def5f 2021-07-02 op #ifdef __NR_fcntl
287 137def5f 2021-07-02 op SC_ALLOW(fcntl),
289 137def5f 2021-07-02 op #ifdef __NR_fcntl64
290 137def5f 2021-07-02 op SC_ALLOW(fcntl64),
292 137def5f 2021-07-02 op #ifdef __NR_fstat
293 137def5f 2021-07-02 op SC_ALLOW(fstat),
295 21f7d246 2021-07-23 op #ifdef __NR_fstat64
296 21f7d246 2021-07-23 op SC_ALLOW(fstat64),
298 94c5f99a 2022-02-13 op #ifdef __NR_fstatat64
299 94c5f99a 2022-02-13 op SC_ALLOW(fstatat64),
301 137def5f 2021-07-02 op #ifdef __NR_getdents64
302 137def5f 2021-07-02 op SC_ALLOW(getdents64),
304 137def5f 2021-07-02 op #ifdef __NR_getpid
305 137def5f 2021-07-02 op SC_ALLOW(getpid),
307 137def5f 2021-07-02 op #ifdef __NR_getrandom
308 137def5f 2021-07-02 op SC_ALLOW(getrandom),
310 137def5f 2021-07-02 op #ifdef __NR_gettimeofday
311 137def5f 2021-07-02 op SC_ALLOW(gettimeofday),
313 137def5f 2021-07-02 op #ifdef __NR_ioctl
314 6f27d259 2021-09-26 op /* allow ioctl on fd 1, glibc doing stuff? */
315 4842c72d 2021-10-18 op SC_ALLOW_ARG(__NR_ioctl, 0, 1),
316 6f27d259 2021-09-26 op /* allow FIONREAD needed by libevent */
317 6f27d259 2021-09-26 op SC_ALLOW_ARG(__NR_ioctl, 1, FIONREAD),
319 94c5f99a 2022-02-13 op #ifdef __NR__llseek
320 94c5f99a 2022-02-13 op SC_ALLOW(_llseek),
322 137def5f 2021-07-02 op #ifdef __NR_lseek
323 137def5f 2021-07-02 op SC_ALLOW(lseek),
325 137def5f 2021-07-02 op #ifdef __NR_madvise
326 137def5f 2021-07-02 op SC_ALLOW(madvise),
328 137def5f 2021-07-02 op #ifdef __NR_mmap
329 137def5f 2021-07-02 op SC_ALLOW(mmap),
331 137def5f 2021-07-02 op #ifdef __NR_mmap2
332 137def5f 2021-07-02 op SC_ALLOW(mmap2),
334 137def5f 2021-07-02 op #ifdef __NR_munmap
335 137def5f 2021-07-02 op SC_ALLOW(munmap),
337 137def5f 2021-07-02 op #ifdef __NR_newfstatat
338 137def5f 2021-07-02 op SC_ALLOW(newfstatat),
340 137def5f 2021-07-02 op #ifdef __NR_oldfstat
341 137def5f 2021-07-02 op SC_ALLOW(oldfstat),
343 137def5f 2021-07-02 op #ifdef __NR_openat
344 4f0e893c 2022-02-13 op SC_ALLOW_ARG(__NR_openat, 3, O_RDONLY),
346 137def5f 2021-07-02 op #ifdef __NR_prlimit64
347 137def5f 2021-07-02 op SC_ALLOW(prlimit64),
349 137def5f 2021-07-02 op #ifdef __NR_read
350 137def5f 2021-07-02 op SC_ALLOW(read),
352 137def5f 2021-07-02 op #ifdef __NR_recvmsg
353 137def5f 2021-07-02 op SC_ALLOW(recvmsg),
355 a8e1e8d7 2021-07-23 op #ifdef __NR_readv
356 a8e1e8d7 2021-07-23 op SC_ALLOW(readv),
358 137def5f 2021-07-02 op #ifdef __NR_rt_sigaction
359 137def5f 2021-07-02 op SC_ALLOW(rt_sigaction),
361 137def5f 2021-07-02 op #ifdef __NR_rt_sigreturn
362 137def5f 2021-07-02 op SC_ALLOW(rt_sigreturn),
364 137def5f 2021-07-02 op #ifdef __NR_sendmsg
365 137def5f 2021-07-02 op SC_ALLOW(sendmsg),
367 94c5f99a 2022-02-13 op #ifdef __NR_sigreturn
368 94c5f99a 2022-02-13 op SC_ALLOW(sigreturn),
370 137def5f 2021-07-02 op #ifdef __NR_statx
371 137def5f 2021-07-02 op SC_ALLOW(statx),
373 63bf54b6 2021-12-11 vdrummer #ifdef __NR_ugetrlimit
374 63bf54b6 2021-12-11 vdrummer SC_ALLOW(ugetrlimit),
376 137def5f 2021-07-02 op #ifdef __NR_write
377 137def5f 2021-07-02 op SC_ALLOW(write),
379 137def5f 2021-07-02 op #ifdef __NR_writev
380 137def5f 2021-07-02 op SC_ALLOW(writev),
383 4aa1dd55 2021-07-03 op /* disallow everything else */
384 137def5f 2021-07-02 op BPF_STMT(BPF_RET | BPF_K, SC_FAIL),
387 71b7eb2f 2021-01-17 op #ifdef SC_DEBUG
389 71b7eb2f 2021-01-17 op #include <signal.h>
390 71b7eb2f 2021-01-17 op #include <unistd.h>
393 71b7eb2f 2021-01-17 op sandbox_seccomp_violation(int signum, siginfo_t *info, void *ctx)
395 71b7eb2f 2021-01-17 op fprintf(stderr, "%s: unexpected system call (arch:0x%x,syscall:%d @ %p)\n",
396 71b7eb2f 2021-01-17 op __func__, info->si_arch, info->si_syscall, info->si_call_addr);
401 71b7eb2f 2021-01-17 op sandbox_seccomp_catch_sigsys(void)
403 71b7eb2f 2021-01-17 op struct sigaction act;
404 71b7eb2f 2021-01-17 op sigset_t mask;
406 71b7eb2f 2021-01-17 op memset(&act, 0, sizeof(act));
407 71b7eb2f 2021-01-17 op sigemptyset(&mask);
408 71b7eb2f 2021-01-17 op sigaddset(&mask, SIGSYS);
410 71b7eb2f 2021-01-17 op act.sa_sigaction = &sandbox_seccomp_violation;
411 71b7eb2f 2021-01-17 op act.sa_flags = SA_SIGINFO;
412 8e56d6ad 2021-02-11 op if (sigaction(SIGSYS, &act, NULL) == -1)
413 8e56d6ad 2021-02-11 op fatal("%s: sigaction(SIGSYS): %s",
414 71b7eb2f 2021-01-17 op __func__, strerror(errno));
416 8e56d6ad 2021-02-11 op if (sigprocmask(SIG_UNBLOCK, &mask, NULL) == -1)
417 8e56d6ad 2021-02-11 op fatal("%s: sigprocmask(SIGSYS): %s\n",
418 71b7eb2f 2021-01-17 op __func__, strerror(errno));
420 71b7eb2f 2021-01-17 op #endif /* SC_DEBUG */
422 3499ce5a 2021-09-19 op #if HAVE_LANDLOCK
423 0ea22af2 2021-09-19 op static inline int
424 cb28978f 2021-09-25 op open_landlock(void)
428 e5d82d94 2022-03-19 op const struct landlock_ruleset_attr attr = {
429 98c6f8de 2022-02-10 op .handled_access_fs = LANDLOCK_ACCESS_FS_EXECUTE |
430 98c6f8de 2022-02-10 op LANDLOCK_ACCESS_FS_READ_FILE |
431 98c6f8de 2022-02-10 op LANDLOCK_ACCESS_FS_READ_DIR |
432 98c6f8de 2022-02-10 op LANDLOCK_ACCESS_FS_WRITE_FILE |
433 98c6f8de 2022-02-10 op LANDLOCK_ACCESS_FS_REMOVE_DIR |
434 98c6f8de 2022-02-10 op LANDLOCK_ACCESS_FS_REMOVE_FILE |
435 98c6f8de 2022-02-10 op LANDLOCK_ACCESS_FS_MAKE_CHAR |
436 98c6f8de 2022-02-10 op LANDLOCK_ACCESS_FS_MAKE_DIR |
437 98c6f8de 2022-02-10 op LANDLOCK_ACCESS_FS_MAKE_REG |
438 98c6f8de 2022-02-10 op LANDLOCK_ACCESS_FS_MAKE_SOCK |
439 98c6f8de 2022-02-10 op LANDLOCK_ACCESS_FS_MAKE_FIFO |
440 98c6f8de 2022-02-10 op LANDLOCK_ACCESS_FS_MAKE_BLOCK |
441 98c6f8de 2022-02-10 op LANDLOCK_ACCESS_FS_MAKE_SYM,
444 cb28978f 2021-09-25 op fd = landlock_create_ruleset(&attr, sizeof(attr), 0);
445 0ea22af2 2021-09-19 op if (fd == -1) {
446 0ea22af2 2021-09-19 op switch (errno) {
448 0ea22af2 2021-09-19 op fatal("%s: failed to create ruleset. "
449 0ea22af2 2021-09-19 op "Landlock doesn't seem to be supported by the "
450 0ea22af2 2021-09-19 op "current kernel.", __func__);
451 0ea22af2 2021-09-19 op case EOPNOTSUPP:
452 0ea22af2 2021-09-19 op log_warn(NULL, "%s: failed to create ruleset. "
453 0ea22af2 2021-09-19 op "Landlock seems to be currently disabled; "
454 0ea22af2 2021-09-19 op "continuing without it.", __func__);
457 0ea22af2 2021-09-19 op fatal("%s: failed to create ruleset: %s",
458 0ea22af2 2021-09-19 op __func__, strerror(errno));
466 cb28978f 2021-09-25 op landlock_unveil_path(int landlock_fd, const char *path, int perms)
468 cb28978f 2021-09-25 op struct landlock_path_beneath_attr pb;
469 cb28978f 2021-09-25 op int err, saved_errno;
471 cb28978f 2021-09-25 op pb.allowed_access = perms;
473 cb28978f 2021-09-25 op if ((pb.parent_fd = open(path, O_PATH)) == -1)
476 cb28978f 2021-09-25 op err = landlock_add_rule(landlock_fd, LANDLOCK_RULE_PATH_BENEATH,
478 cb28978f 2021-09-25 op saved_errno = errno;
479 cb28978f 2021-09-25 op close(pb.parent_fd);
480 cb28978f 2021-09-25 op errno = saved_errno;
481 cb28978f 2021-09-25 op return err ? -1 : 0;
485 cb28978f 2021-09-25 op landlock_apply(int fd)
487 cb28978f 2021-09-25 op int r, saved_errno;
489 cb28978f 2021-09-25 op if (fd == -1)
492 cb28978f 2021-09-25 op r = landlock_restrict_self(fd, 0);
493 cb28978f 2021-09-25 op saved_errno = errno;
495 cb28978f 2021-09-25 op errno = saved_errno;
496 cb28978f 2021-09-25 op return r ? -1 : 0;
500 3499ce5a 2021-09-19 op server_landlock(void)
502 cb28978f 2021-09-25 op int fd, perms;
503 3499ce5a 2021-09-19 op struct vhost *h;
504 3499ce5a 2021-09-19 op struct location *l;
507 3499ce5a 2021-09-19 op * These are all the actions allowed for the root directories
508 cb28978f 2021-09-25 op * of the vhosts.
510 cb28978f 2021-09-25 op perms = LANDLOCK_ACCESS_FS_READ_FILE | LANDLOCK_ACCESS_FS_READ_DIR;
512 cb28978f 2021-09-25 op if ((fd = open_landlock()) == -1)
515 3499ce5a 2021-09-19 op TAILQ_FOREACH(h, &hosts, vhosts) {
516 3499ce5a 2021-09-19 op TAILQ_FOREACH(l, &h->locations, locations) {
517 3499ce5a 2021-09-19 op if (l->dir == NULL)
520 cb28978f 2021-09-25 op if (landlock_unveil_path(fd, l->dir, perms) == -1)
521 cb28978f 2021-09-25 op fatal("%s: landlock_unveil_path(%s): %s",
522 3499ce5a 2021-09-19 op __func__, l->dir, strerror(errno));
526 cb28978f 2021-09-25 op return landlock_apply(fd);
530 b0be0653 2021-09-19 op logger_landlock(void)
534 cb28978f 2021-09-25 op if ((fd = open_landlock()) == -1)
537 cb28978f 2021-09-25 op /* no rules. the logger doesn't need fs access at all. */
539 cb28978f 2021-09-25 op return landlock_apply(fd);
544 76000995 2022-09-06 op sandbox_server_process(int can_open_sockets)
546 e5d82d94 2022-03-19 op const struct sock_fprog prog = {
547 71b7eb2f 2021-01-17 op .len = (unsigned short) (sizeof(filter) / sizeof(filter[0])),
548 71b7eb2f 2021-01-17 op .filter = filter,
551 76000995 2022-09-06 op /* can't seccomp/landlock if fastcgi or proxying are used. */
552 76000995 2022-09-06 op if (can_open_sockets)
556 71b7eb2f 2021-01-17 op #ifdef SC_DEBUG
557 71b7eb2f 2021-01-17 op sandbox_seccomp_catch_sigsys();
560 8e56d6ad 2021-02-11 op if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) == -1)
561 8e56d6ad 2021-02-11 op fatal("%s: prctl(PR_SET_NO_NEW_PRIVS): %s",
562 71b7eb2f 2021-01-17 op __func__, strerror(errno));
564 3499ce5a 2021-09-19 op #if HAVE_LANDLOCK
565 cb28978f 2021-09-25 op if (server_landlock() == -1)
566 cb28978f 2021-09-25 op fatal("%s: server_landlock: %s",
567 cb28978f 2021-09-25 op __func__, strerror(errno));
570 8e56d6ad 2021-02-11 op if (prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog) == -1)
571 8e56d6ad 2021-02-11 op fatal("%s: prctl(PR_SET_SECCOMP): %s\n",
572 71b7eb2f 2021-01-17 op __func__, strerror(errno));
576 62e001b0 2021-03-20 op sandbox_logger_process(void)
579 b0be0653 2021-09-19 op * Here we could use a seccomp filter to allow only recvfd,
580 b0be0653 2021-09-19 op * write/writev and memory allocations, but syslog is a beast
581 b0be0653 2021-09-19 op * and I don't know what syscalls it could end up doing.
582 b0be0653 2021-09-19 op * Landlock is a simpler beast, use it to disallow any file
583 b0be0653 2021-09-19 op * sytsem access.
586 f7ee7990 2021-10-02 op if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) == -1)
587 f7ee7990 2021-10-02 op fatal("%s: prctl(PR_SET_NO_NEW_PRIVS): %s",
588 f7ee7990 2021-10-02 op __func__, strerror(errno));
590 b0be0653 2021-09-19 op #if HAVE_LANDLOCK
591 cb28978f 2021-09-25 op if (logger_landlock() == -1)
592 cb28978f 2021-09-25 op fatal("%s: logger_landlock: %s",
593 b0be0653 2021-09-19 op __func__, strerror(errno));
599 dafb57b8 2021-01-15 op #elif defined(__OpenBSD__)
601 dafb57b8 2021-01-15 op #include <unistd.h>
604 76000995 2022-09-06 op sandbox_server_process(int can_open_sockets)
606 fdea6aa0 2021-04-30 op struct vhost *h;
607 fdea6aa0 2021-04-30 op struct location *l;
609 b8e64ccd 2021-03-31 op TAILQ_FOREACH(h, &hosts, vhosts) {
610 fdea6aa0 2021-04-30 op TAILQ_FOREACH(l, &h->locations, locations) {
611 fdea6aa0 2021-04-30 op if (l->dir == NULL)
614 fdea6aa0 2021-04-30 op if (unveil(l->dir, "r") == -1)
615 fdea6aa0 2021-04-30 op fatal("unveil %s for domain %s",
621 d29a2ee2 2022-09-06 op if (pledge("stdio recvfd rpath inet dns", NULL) == -1)
622 8e56d6ad 2021-02-11 op fatal("pledge");
626 62e001b0 2021-03-20 op sandbox_logger_process(void)
628 e952c505 2021-06-15 op if (pledge("stdio recvfd", NULL) == -1)
629 62e001b0 2021-03-20 op err(1, "pledge");
634 62e001b0 2021-03-20 op #warning "No sandbox method known for this OS"
637 76000995 2022-09-06 op sandbox_server_process(int can_open_sockets)
643 62e001b0 2021-03-20 op sandbox_logger_process(void)