kern_ssp.c revision 1.2.4.2
1 1.2.4.2 snj /* $NetBSD: kern_ssp.c,v 1.2.4.2 2009/03/15 19:43:48 snj Exp $ */ 2 1.2.4.2 snj 3 1.2.4.2 snj /*- 4 1.2.4.2 snj * Copyright (c) 2008 The NetBSD Foundation, Inc. 5 1.2.4.2 snj * All rights reserved. 6 1.2.4.2 snj * 7 1.2.4.2 snj * Redistribution and use in source and binary forms, with or without 8 1.2.4.2 snj * modification, are permitted provided that the following conditions 9 1.2.4.2 snj * are met: 10 1.2.4.2 snj * 1. Redistributions of source code must retain the above copyright 11 1.2.4.2 snj * notice, this list of conditions and the following disclaimer. 12 1.2.4.2 snj * 2. Redistributions in binary form must reproduce the above copyright 13 1.2.4.2 snj * notice, this list of conditions and the following disclaimer in the 14 1.2.4.2 snj * documentation and/or other materials provided with the distribution. 15 1.2.4.2 snj * 16 1.2.4.2 snj * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 1.2.4.2 snj * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 1.2.4.2 snj * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 1.2.4.2 snj * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 1.2.4.2 snj * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 1.2.4.2 snj * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 1.2.4.2 snj * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 1.2.4.2 snj * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 1.2.4.2 snj * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 1.2.4.2 snj * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 1.2.4.2 snj * POSSIBILITY OF SUCH DAMAGE. 27 1.2.4.2 snj */ 28 1.2.4.2 snj 29 1.2.4.2 snj #include <sys/cdefs.h> 30 1.2.4.2 snj __KERNEL_RCSID(0, "$NetBSD: kern_ssp.c,v 1.2.4.2 2009/03/15 19:43:48 snj Exp $"); 31 1.2.4.2 snj 32 1.2.4.2 snj #include <sys/systm.h> 33 1.2.4.2 snj #include <sys/intr.h> 34 1.2.4.2 snj 35 1.2.4.2 snj #if defined(__SSP__) || defined(__SSP_ALL__) 36 1.2.4.2 snj long __stack_chk_guard[8] = {0, 0, 0, 0, 0, 0, 0, 0}; 37 1.2.4.2 snj void __stack_chk_fail(void); 38 1.2.4.2 snj 39 1.2.4.2 snj void 40 1.2.4.2 snj __stack_chk_fail(void) 41 1.2.4.2 snj { 42 1.2.4.2 snj panic("stack overflow detected; terminated"); 43 1.2.4.2 snj } 44 1.2.4.2 snj 45 1.2.4.2 snj void 46 1.2.4.2 snj ssp_init(void) 47 1.2.4.2 snj { 48 1.2.4.2 snj int s; 49 1.2.4.2 snj 50 1.2.4.2 snj #ifdef DIAGNOSTIC 51 1.2.4.2 snj printf("Initializing SSP:"); 52 1.2.4.2 snj #endif 53 1.2.4.2 snj /* 54 1.2.4.2 snj * We initialize ssp here carefully: 55 1.2.4.2 snj * 1. after we got some entropy 56 1.2.4.2 snj * 2. without calling a function 57 1.2.4.2 snj */ 58 1.2.4.2 snj size_t i; 59 1.2.4.2 snj long guard[__arraycount(__stack_chk_guard)]; 60 1.2.4.2 snj 61 1.2.4.2 snj arc4randbytes(guard, sizeof(guard)); 62 1.2.4.2 snj s = splhigh(); 63 1.2.4.2 snj for (i = 0; i < __arraycount(guard); i++) 64 1.2.4.2 snj __stack_chk_guard[i] = guard[i]; 65 1.2.4.2 snj splx(s); 66 1.2.4.2 snj #ifdef DIAGNOSTIC 67 1.2.4.2 snj for (i = 0; i < __arraycount(guard); i++) 68 1.2.4.2 snj printf("%lx ", guard[i]); 69 1.2.4.2 snj printf("\n"); 70 1.2.4.2 snj #endif 71 1.2.4.2 snj } 72 1.2.4.2 snj #else 73 1.2.4.2 snj void 74 1.2.4.2 snj ssp_init(void) 75 1.2.4.2 snj { 76 1.2.4.2 snj } 77 1.2.4.2 snj #endif 78
Indexes created Tue Oct 07 21:09:53 GMT 2025