1 /* $OpenBSD: sandbox-rlimit.c,v 1.5 2020/10/18 11:32:01 djm Exp $ */ 2 /* 3 * Copyright (c) 2011 Damien Miller <djm@mindrot.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #include "includes.h" 19 20 #ifdef SANDBOX_RLIMIT 21 22 #include <sys/types.h> 23 #include <sys/time.h> 24 #include <sys/resource.h> 25 26 #include <errno.h> 27 #include <stdarg.h> 28 #include <stdio.h> 29 #include <stdlib.h> 30 #include <string.h> 31 #include <unistd.h> 32 33 #include "log.h" 34 #include "ssh-sandbox.h" 35 #include "xmalloc.h" 36 37 /* Minimal sandbox that sets zero nfiles, nprocs and filesize rlimits */ 38 39 struct ssh_sandbox { 40 int junk; 41 }; 42 43 struct ssh_sandbox * 44 ssh_sandbox_init(struct monitor *monitor) 45 { 46 struct ssh_sandbox *box; 47 48 /* 49 * Strictly, we don't need to maintain any state here but we need 50 * to return non-NULL to satisfy the API. 51 */ 52 debug3_f("preparing rlimit sandbox"); 53 box = xcalloc(1, sizeof(*box)); 54 return box; 55 } 56 57 void 58 ssh_sandbox_child(struct ssh_sandbox *box) 59 { 60 struct rlimit rl_zero; 61 62 rl_zero.rlim_cur = rl_zero.rlim_max = 0; 63 64 #ifndef SANDBOX_SKIP_RLIMIT_FSIZE 65 if (setrlimit(RLIMIT_FSIZE, &rl_zero) == -1) 66 fatal_f("setrlimit(RLIMIT_FSIZE, { 0, 0 }): %s", 67 strerror(errno)); 68 #endif 69 #ifndef SANDBOX_SKIP_RLIMIT_NOFILE 70 if (setrlimit(RLIMIT_NOFILE, &rl_zero) == -1) 71 fatal_f("setrlimit(RLIMIT_NOFILE, { 0, 0 }): %s", 72 strerror(errno)); 73 #endif 74 #ifdef HAVE_RLIMIT_NPROC 75 if (setrlimit(RLIMIT_NPROC, &rl_zero) == -1) 76 fatal_f("setrlimit(RLIMIT_NPROC, { 0, 0 }): %s", 77 strerror(errno)); 78 #endif 79 } 80 81 #endif /* SANDBOX_RLIMIT */ 82