kern_ssp.c revision 1.2.2.2
1 1.2.2.2 skrll /* $NetBSD: kern_ssp.c,v 1.2.2.2 2009/03/03 18:32:56 skrll Exp $ */ 2 1.2.2.2 skrll 3 1.2.2.2 skrll /*- 4 1.2.2.2 skrll * Copyright (c) 2008 The NetBSD Foundation, Inc. 5 1.2.2.2 skrll * All rights reserved. 6 1.2.2.2 skrll * 7 1.2.2.2 skrll * Redistribution and use in source and binary forms, with or without 8 1.2.2.2 skrll * modification, are permitted provided that the following conditions 9 1.2.2.2 skrll * are met: 10 1.2.2.2 skrll * 1. Redistributions of source code must retain the above copyright 11 1.2.2.2 skrll * notice, this list of conditions and the following disclaimer. 12 1.2.2.2 skrll * 2. Redistributions in binary form must reproduce the above copyright 13 1.2.2.2 skrll * notice, this list of conditions and the following disclaimer in the 14 1.2.2.2 skrll * documentation and/or other materials provided with the distribution. 15 1.2.2.2 skrll * 16 1.2.2.2 skrll * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 1.2.2.2 skrll * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 1.2.2.2 skrll * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 1.2.2.2 skrll * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 1.2.2.2 skrll * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 1.2.2.2 skrll * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 1.2.2.2 skrll * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 1.2.2.2 skrll * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 1.2.2.2 skrll * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 1.2.2.2 skrll * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 1.2.2.2 skrll * POSSIBILITY OF SUCH DAMAGE. 27 1.2.2.2 skrll */ 28 1.2.2.2 skrll 29 1.2.2.2 skrll #include <sys/cdefs.h> 30 1.2.2.2 skrll __KERNEL_RCSID(0, "$NetBSD: kern_ssp.c,v 1.2.2.2 2009/03/03 18:32:56 skrll Exp $"); 31 1.2.2.2 skrll 32 1.2.2.2 skrll #include <sys/param.h> 33 1.2.2.2 skrll #include <sys/systm.h> 34 1.2.2.2 skrll #include <sys/intr.h> 35 1.2.2.2 skrll 36 1.2.2.2 skrll #if defined(__SSP__) || defined(__SSP_ALL__) 37 1.2.2.2 skrll long __stack_chk_guard[8] = {0, 0, 0, 0, 0, 0, 0, 0}; 38 1.2.2.2 skrll void __stack_chk_fail(void); 39 1.2.2.2 skrll 40 1.2.2.2 skrll void 41 1.2.2.2 skrll __stack_chk_fail(void) 42 1.2.2.2 skrll { 43 1.2.2.2 skrll panic("stack overflow detected; terminated"); 44 1.2.2.2 skrll } 45 1.2.2.2 skrll 46 1.2.2.2 skrll void 47 1.2.2.2 skrll ssp_init(void) 48 1.2.2.2 skrll { 49 1.2.2.2 skrll int s; 50 1.2.2.2 skrll 51 1.2.2.2 skrll #ifdef DIAGNOSTIC 52 1.2.2.2 skrll printf("Initializing SSP:"); 53 1.2.2.2 skrll #endif 54 1.2.2.2 skrll /* 55 1.2.2.2 skrll * We initialize ssp here carefully: 56 1.2.2.2 skrll * 1. after we got some entropy 57 1.2.2.2 skrll * 2. without calling a function 58 1.2.2.2 skrll */ 59 1.2.2.2 skrll size_t i; 60 1.2.2.2 skrll long guard[__arraycount(__stack_chk_guard)]; 61 1.2.2.2 skrll 62 1.2.2.2 skrll arc4randbytes(guard, sizeof(guard)); 63 1.2.2.2 skrll s = splhigh(); 64 1.2.2.2 skrll for (i = 0; i < __arraycount(guard); i++) 65 1.2.2.2 skrll __stack_chk_guard[i] = guard[i]; 66 1.2.2.2 skrll splx(s); 67 1.2.2.2 skrll #ifdef DIAGNOSTIC 68 1.2.2.2 skrll for (i = 0; i < __arraycount(guard); i++) 69 1.2.2.2 skrll printf("%lx ", guard[i]); 70 1.2.2.2 skrll printf("\n"); 71 1.2.2.2 skrll #endif 72 1.2.2.2 skrll } 73 1.2.2.2 skrll #else 74 1.2.2.2 skrll void 75 1.2.2.2 skrll ssp_init(void) 76 1.2.2.2 skrll { 77 1.2.2.2 skrll } 78 1.2.2.2 skrll #endif 79
Indexes created Tue Oct 07 21:09:53 GMT 2025