1 /* $OpenBSD: sandbox-rlimit.c,v 1.3 2011/06/23 09:34:13 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/param.h> 24 #include <sys/time.h> 25 #include <sys/resource.h> 26 27 #include <errno.h> 28 #include <stdarg.h> 29 #include <stdio.h> 30 #include <stdlib.h> 31 #include <string.h> 32 #include <unistd.h> 33 34 #include "log.h" 35 #include "ssh-sandbox.h" 36 #include "xmalloc.h" 37 38 /* Minimal sandbox that sets zero nfiles, nprocs and filesize rlimits */ 39 40 struct ssh_sandbox { 41 pid_t child_pid; 42 }; 43 44 struct ssh_sandbox * 45 ssh_sandbox_init(void) 46 { 47 struct ssh_sandbox *box; 48 49 /* 50 * Strictly, we don't need to maintain any state here but we need 51 * to return non-NULL to satisfy the API. 52 */ 53 debug3("%s: preparing rlimit sandbox", __func__); 54 box = xcalloc(1, sizeof(*box)); 55 box->child_pid = 0; 56 57 return box; 58 } 59 60 void 61 ssh_sandbox_child(struct ssh_sandbox *box) 62 { 63 struct rlimit rl_zero; 64 65 rl_zero.rlim_cur = rl_zero.rlim_max = 0; 66 67 if (setrlimit(RLIMIT_FSIZE, &rl_zero) == -1) 68 fatal("%s: setrlimit(RLIMIT_FSIZE, { 0, 0 }): %s", 69 __func__, strerror(errno)); 70 if (setrlimit(RLIMIT_NOFILE, &rl_zero) == -1) 71 fatal("%s: setrlimit(RLIMIT_NOFILE, { 0, 0 }): %s", 72 __func__, strerror(errno)); 73 #ifdef HAVE_RLIMIT_NPROC 74 if (setrlimit(RLIMIT_NPROC, &rl_zero) == -1) 75 fatal("%s: setrlimit(RLIMIT_NPROC, { 0, 0 }): %s", 76 __func__, strerror(errno)); 77 #endif 78 } 79 80 void 81 ssh_sandbox_parent_finish(struct ssh_sandbox *box) 82 { 83 free(box); 84 debug3("%s: finished", __func__); 85 } 86 87 void 88 ssh_sandbox_parent_preauth(struct ssh_sandbox *box, pid_t child_pid) 89 { 90 box->child_pid = child_pid; 91 } 92 93 #endif /* SANDBOX_RLIMIT */ 94