1/* $OpenBSD: sigsetjmp.S,v 1.4 2023/12/10 16:45:52 deraadt Exp $ */ 2/* 3 * Copyright (c) 2020 Dale Rahn. All rights reserved. 4 * 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27#include "SYS.h" 28#include <machine/asm.h> 29 30#define JMP_sigflag 0x00 31#define JMP_r1 0x08 32#define JMP_r14 0x10 33#define JMP_r15 0x18 34#define JMP_r16 0x20 35#define JMP_r17 0x28 36#define JMP_r18 0x30 37#define JMP_r19 0x38 38#define JMP_r20 0x40 39#define JMP_r21 0x48 40#define JMP_r22 0x50 41#define JMP_r23 0x58 42#define JMP_r24 0x60 43#define JMP_r25 0x68 44#define JMP_r26 0x70 45#define JMP_r27 0x78 46#define JMP_r28 0x80 47#define JMP_r29 0x88 48#define JMP_r30 0x90 49#define JMP_r31 0x98 50#define JMP_lr 0xa0 51#define JMP_cr 0xa8 52#define JMP_ctr 0xb0 53#define JMP_xer 0xb8 54#define JMP_sig 0xc0 55#define JMP_sigmask 0xc8 56 57 58 .extern __jmpxor 59 60/* int sigsetjmp(sigjmp_buf env, int savemask) */ 61ENTRY(sigsetjmp) 62 RETGUARD_SETUP(sigsetjmp, %r11) 63 mr %r5, %r3 /* save jmpbuf addr in r5 */ 64 std %r4, JMP_sigflag(%r5) 65 or. %r4, %r4, %r4 66 beq 1f 67 li %r3, 1 /* how = SIG_BLOCK */ 68 li %r4, 0 /* oset = empty */ 69 li %r0, SYS_sigprocmask 7099: sc 71 PINSYSCALL(SYS_sigprocmask, 99b) 72 nop 73 std %r3, JMP_sigmask(5) 741: 75 addis %r7, %r2, __jmpxor@toc@ha 76 addi %r7, %r7, __jmpxor@toc@l 77 ld %r8, 0(%r7) /* xor for r1 */ 78 ld %r7, 8(%r7) /* xor for lr, overwrite addr */ 79 80 /* r1, r14-r31 */ 81 xor %r0, %r8, %r1 /* use and overwrite the r1 xor */ 82 std %r0, JMP_r1 (%r5) 83 std %r14, JMP_r14(%r5) 84 std %r15, JMP_r15(%r5) 85 std %r16, JMP_r16(%r5) 86 std %r17, JMP_r17(%r5) 87 std %r18, JMP_r18(%r5) 88 std %r19, JMP_r19(%r5) 89 std %r20, JMP_r20(%r5) 90 std %r21, JMP_r21(%r5) 91 std %r22, JMP_r22(%r5) 92 std %r23, JMP_r23(%r5) 93 std %r24, JMP_r24(%r5) 94 std %r25, JMP_r25(%r5) 95 std %r26, JMP_r26(%r5) 96 std %r27, JMP_r27(%r5) 97 std %r28, JMP_r28(%r5) 98 std %r29, JMP_r29(%r5) 99 std %r30, JMP_r30(%r5) 100 std %r31, JMP_r31(%r5) 101 /* lr, cr, ctr, xer */ 102 mflr %r0 103 xor %r7, %r0, %r7 /* use and overwrite the lr xor */ 104 std %r7, JMP_lr(%r5) 105 mfcr %r0 106 std %r0, JMP_cr(%r5) 107 mfctr %r0 108 std %r0, JMP_ctr(%r5) 109 mfctr %r0 110 mfxer %r0 111 std %r0, JMP_xer(%r5) 112 /* f14-f31, fpscr */ 113 li %r3, 0 114 RETGUARD_CHECK(sigsetjmp, %r11) 115 blr 116END(sigsetjmp) 117 118 119/* int siglongjmp(sigjmp_buf env, int val) */ 120ENTRY(siglongjmp) 121 mr %r5, %r3 /* save jmpbuf addr in r5 */ 122 mr %r6, %r4 /* save val in r6 */ 123 ld %r4, JMP_sigflag(%r5) /* do we need to restore sigmask? */ 124 or. %r4, %r4, %r4 125 beq 1f 126 127 li %r3, 3 /* how = SIG_SETMASK */ 128 ld %r4, JMP_sigmask(%r5) /* oset from the jmpbuf */ 129 li %r0, SYS_sigprocmask 13098: sc 131 PINSYSCALL(SYS_sigprocmask, 98b) 1321: 133 addis %r9, %r2, __jmpxor@toc@ha 134 addi %r9, %r9, __jmpxor@toc@l 135 ld %r8, 0(%r9) /* xor for r1 */ 136 ld %r9, 8(%r9) /* xor for lr, overwrite addr */ 137 ld %r0, JMP_lr(%r5) 138 xor %r0, %r0, %r9 /* use the lr xor */ 139 mtlr %r0 140 RETGUARD_SETUP(siglongjmp, %r11) 141 142 /* r1, r14-r31 */ 143 ld %r0, JMP_r1(%r5) 144 xor %r1, %r0, %r8 /* use the r1 xor */ 145 ld %r14, JMP_r14(%r5) 146 ld %r15, JMP_r15(%r5) 147 ld %r16, JMP_r16(%r5) 148 ld %r17, JMP_r17(%r5) 149 ld %r18, JMP_r18(%r5) 150 ld %r19, JMP_r19(%r5) 151 ld %r20, JMP_r20(%r5) 152 ld %r21, JMP_r21(%r5) 153 ld %r22, JMP_r22(%r5) 154 ld %r23, JMP_r23(%r5) 155 ld %r24, JMP_r24(%r5) 156 ld %r25, JMP_r25(%r5) 157 ld %r26, JMP_r26(%r5) 158 ld %r27, JMP_r27(%r5) 159 ld %r28, JMP_r28(%r5) 160 ld %r29, JMP_r29(%r5) 161 ld %r30, JMP_r30(%r5) 162 ld %r31, JMP_r31(%r5) 163 /* cr, lr, ctr, xer */ 164 ld %r8, JMP_cr(%r5) /* overwrite the r1 xor */ 165 mtcr %r8 166 ld %r9, JMP_ctr(%r5) /* overwrite the lr xor */ 167 mtctr %r9 168 ld %r0, JMP_xer(%r5) 169 mtxer %r0 170 /* floating point is all caller save */ 171 172 /* if return val in r6 == 0, return 1, not 0 */ 173 mr %r3, %r6 174 cmpwi %r6, 0 175 bne 2f 176 li %r3, 1 1772: 178 RETGUARD_CHECK(siglongjmp, %r11) 179 blr 180END(siglongjmp) 181