1 /*- 2 * Copyright (c) 2007 Robert M. M. Watson 3 * All rights reserved. 4 * 5 * This software was developed by Robert N. M. Watson for the TrustedBSD 6 * Project. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR, NCIRCLE NETWORK SECURITY, 21 * INC., OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 23 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 24 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 25 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 26 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 27 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32 /* 33 * Confirm that when security.bsd.unprivileged_read_msgbuf is set to 0, 34 * privilege is required to read the kernel message buffer. 35 */ 36 37 #include <sys/types.h> 38 #include <sys/sysctl.h> 39 40 #include <err.h> 41 #include <errno.h> 42 #include <stdio.h> 43 44 #include "main.h" 45 46 #define MSGBUF_CONTROL_NAME "security.bsd.unprivileged_read_msgbuf" 47 #define MSGBUF_NAME "kern.msgbuf" 48 49 /* 50 * We must query and save the original value, then restore it when done. 51 */ 52 static int unprivileged_read_msgbuf; 53 static int unprivileged_read_msgbuf_initialized; 54 55 int 56 priv_msgbuf_privonly_setup(int asroot, int injail, struct test *test) 57 { 58 size_t len; 59 int newval; 60 61 /* 62 * Separately query and set to make debugging easier. 63 */ 64 len = sizeof(unprivileged_read_msgbuf); 65 if (sysctlbyname(MSGBUF_CONTROL_NAME, &unprivileged_read_msgbuf, 66 &len, NULL, 0) < 0) { 67 warn("priv_msgbuf_privonly_setup: sysctlbyname query"); 68 return (-1); 69 } 70 newval = 0; 71 if (sysctlbyname(MSGBUF_CONTROL_NAME, NULL, NULL, &newval, 72 sizeof(newval)) < 0) { 73 warn("priv_msgbuf_privonly_setup: sysctlbyname set"); 74 return (-1); 75 } 76 unprivileged_read_msgbuf_initialized = 1; 77 return (0); 78 } 79 80 void 81 priv_msgbuf_privonly(int asroot, int injail, struct test *test) 82 { 83 size_t len; 84 int error; 85 86 error = sysctlbyname(MSGBUF_NAME, NULL, &len, NULL, 0); 87 if (asroot && injail) 88 expect("priv_msgbuf_privonly(asroot, injail)", error, -1, 89 EPERM); 90 if (asroot && !injail) 91 expect("priv_msgbuf_privonly(asroot, !injail)", error, 0, 0); 92 if (!asroot && injail) 93 expect("priv_msgbuf_privonly(!asroot, injail)", error, -1, 94 EPERM); 95 if (!asroot && !injail) 96 expect("priv_msgbuf_privonly(!asroot, !injail)", error, -1, 97 EPERM); 98 } 99 100 int 101 priv_msgbuf_unprivok_setup(int asroot, int injail, struct test *test) 102 { 103 size_t len; 104 int newval; 105 106 /* 107 * Separately query and set to make debugging easier. 108 */ 109 len = sizeof(unprivileged_read_msgbuf); 110 if (sysctlbyname(MSGBUF_CONTROL_NAME, &unprivileged_read_msgbuf, &len, 111 NULL, 0) < 0) { 112 warn("priv_msgbuf_unprivok_setup: sysctlbyname query"); 113 return (-1); 114 } 115 newval = 1; 116 if (sysctlbyname(MSGBUF_CONTROL_NAME, NULL, NULL, &newval, 117 sizeof(newval)) < 0) { 118 warn("priv_msgbuf_unprivok_setup: sysctlbyname set"); 119 return (-1); 120 } 121 unprivileged_read_msgbuf_initialized = 1; 122 return (0); 123 } 124 125 void 126 priv_msgbuf_unprivok(int asroot, int injail, struct test *test) 127 { 128 size_t len; 129 int error; 130 131 error = sysctlbyname(MSGBUF_NAME, NULL, &len, NULL, 0); 132 if (asroot && injail) 133 expect("priv_msgbuf_unprivok(asroot, injail)", error, 0, 0); 134 if (asroot && !injail) 135 expect("priv_msgbuf_unprivok(asroot, !injail)", error, 0, 0); 136 if (!asroot && injail) 137 expect("priv_msgbuf_unprivok(!asroot, injail)", error, 0, 0); 138 if (!asroot && !injail) 139 expect("priv_msgbuf_unprivok(!asroot, !injail)", error, 0, 0); 140 } 141 142 void 143 priv_msgbuf_cleanup(int asroot, int injail, struct test *test) 144 { 145 146 if (unprivileged_read_msgbuf_initialized) { 147 (void)sysctlbyname(MSGBUF_NAME, NULL, NULL, 148 &unprivileged_read_msgbuf, 149 sizeof(unprivileged_read_msgbuf)); 150 unprivileged_read_msgbuf_initialized = 0; 151 } 152 } 153