/* $OpenBSD: setjmp.S,v 1.13 2023/12/10 16:45:51 deraadt Exp $ */ /* * Copyright (c) 2001-2002 Opsycon AB (www.opsycon.se / www.opsycon.com) * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of Opsycon AB nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * */ #include "SYS.h" #include #include .section .openbsd.randomdata,"aw",@progbits .balign 8 .globl __jmpxor .hidden __jmpxor __jmpxor: .space 3*REGSZ # (28/gp, 29/sp, 31/ra) .size __jmpxor, . - __jmpxor .type __jmpxor,@object .text /* * setjmp, longjmp implementation for libc. this code depends * on the layout of the struct sigcontext in machine/signal.h. */ FRAMESZ= MKFSIZ(0,4) GPOFF= FRAMESZ-2*REGSZ LEAF(setjmp, FRAMESZ) PTR_SUBU sp, FRAMESZ SETUP_GP64(GPOFF, setjmp) .set noreorder move a2, a0 # save jmpbuf li a0, 1 # how = SIG_BLOCK move a1, zero # get current signal mask li v0, SYS_sigprocmask 99: syscall # mask in v0 PINSYSCALL(SYS_sigprocmask, 99b) bne a3, zero, botch REG_S v0, _JB_MASK(a2) # save sc_mask LI v0, 0xACEDBADE # sigcontext magic number REG_S v0, _JB_REGS+ZERO*REGSZ(a2) REG_S s0, _JB_REGS+S0*REGSZ(a2) REG_S s1, _JB_REGS+S1*REGSZ(a2) REG_S s2, _JB_REGS+S2*REGSZ(a2) REG_S s3, _JB_REGS+S3*REGSZ(a2) REG_S s4, _JB_REGS+S4*REGSZ(a2) REG_S s5, _JB_REGS+S5*REGSZ(a2) REG_S s6, _JB_REGS+S6*REGSZ(a2) REG_S s7, _JB_REGS+S7*REGSZ(a2) REG_S s8, _JB_REGS+S8*REGSZ(a2) LA t0, __jmpxor # load cookie addr REG_L v0, 0(t0) # load gp cookie REG_L v1, GPOFF(sp) xor v0, v0, v1 REG_S v0, _JB_REGS+GP*REGSZ(a2) REG_L v0, REGSZ(t0) # load sp cookie over gp cookie PTR_ADDU v1, sp, FRAMESZ xor v0, v0, v1 REG_S v0, _JB_REGS+SP*REGSZ(a2) REG_L t0, 2*REGSZ(t0) # load ra cookie over addr xor t0, ra, t0 REG_S t0, _JB_PC(a2) cfc1 t0, $31 # overwrite ra cookie #if _MIPS_FPSET == 32 sdc1 $f20, _JB_FPREGS+((F20-F0)*REGSZ)(a2) sdc1 $f21, _JB_FPREGS+((F21-F0)*REGSZ)(a2) sdc1 $f22, _JB_FPREGS+((F22-F0)*REGSZ)(a2) sdc1 $f23, _JB_FPREGS+((F23-F0)*REGSZ)(a2) sdc1 $f24, _JB_FPREGS+((F24-F0)*REGSZ)(a2) sdc1 $f25, _JB_FPREGS+((F25-F0)*REGSZ)(a2) sdc1 $f26, _JB_FPREGS+((F26-F0)*REGSZ)(a2) sdc1 $f27, _JB_FPREGS+((F27-F0)*REGSZ)(a2) sdc1 $f28, _JB_FPREGS+((F28-F0)*REGSZ)(a2) sdc1 $f29, _JB_FPREGS+((F29-F0)*REGSZ)(a2) sdc1 $f30, _JB_FPREGS+((F30-F0)*REGSZ)(a2) sdc1 $f31, _JB_FPREGS+((F31-F0)*REGSZ)(a2) #else swc1 $f20, _JB_FPREGS+((F20-F0)*REGSZ)(a2) swc1 $f21, _JB_FPREGS+((F21-F0)*REGSZ)(a2) swc1 $f22, _JB_FPREGS+((F22-F0)*REGSZ)(a2) swc1 $f23, _JB_FPREGS+((F23-F0)*REGSZ)(a2) swc1 $f24, _JB_FPREGS+((F24-F0)*REGSZ)(a2) swc1 $f25, _JB_FPREGS+((F25-F0)*REGSZ)(a2) swc1 $f26, _JB_FPREGS+((F26-F0)*REGSZ)(a2) swc1 $f27, _JB_FPREGS+((F27-F0)*REGSZ)(a2) swc1 $f28, _JB_FPREGS+((F28-F0)*REGSZ)(a2) swc1 $f29, _JB_FPREGS+((F29-F0)*REGSZ)(a2) swc1 $f30, _JB_FPREGS+((F30-F0)*REGSZ)(a2) swc1 $f31, _JB_FPREGS+((F31-F0)*REGSZ)(a2) #endif REG_S t0, _JB_FPREGS+((FSR-F0)*REGSZ)(a2) RESTORE_GP64 PTR_ADDU sp, FRAMESZ j ra move v0, zero END_STRONG(setjmp) LEAF(longjmp, FRAMESZ) PTR_SUBU sp, FRAMESZ SETUP_GP64(GPOFF, longjmp) .set noreorder move a2, a0 # save jmpbuf move a4, a1 # save val REG_L a1, _JB_MASK(a2) # load sc_mask li a0, 3 # how = SIG_SETMASK li v0, SYS_sigprocmask 98: syscall PINSYSCALL(SYS_sigprocmask, 98b) bne a3, zero, botch REG_L v0, _JB_REGS+ZERO*REGSZ(a2) bne v0, 0xACEDBADE, botch # jump if error LA v0, __jmpxor # load cookie addr REG_L v1, 2*REGSZ(v0) # load ra cookie REG_L ra, _JB_PC(a2) xor ra, ra, v1 REG_L s0, _JB_REGS+S0*REGSZ(a2) REG_L s1, _JB_REGS+S1*REGSZ(a2) REG_L s2, _JB_REGS+S2*REGSZ(a2) REG_L s3, _JB_REGS+S3*REGSZ(a2) REG_L s4, _JB_REGS+S4*REGSZ(a2) REG_L s5, _JB_REGS+S5*REGSZ(a2) REG_L s6, _JB_REGS+S6*REGSZ(a2) REG_L s7, _JB_REGS+S7*REGSZ(a2) REG_L s8, _JB_REGS+S8*REGSZ(a2) REG_L v1, 0(v0) # load gp cookie over ra cookie REG_L gp, _JB_REGS+GP*REGSZ(a2) xor gp, gp, v1 REG_L v1, REGSZ(v0) # load sp cookie over gp cookie REG_L sp, _JB_REGS+SP*REGSZ(a2) xor sp, sp, v1 REG_L v1, _JB_FPREGS+((FSR-F0)*REGSZ)(a2) # overwrite sp cookie ctc1 v1, $31 #if _MIPS_FPSET == 32 ldc1 $f20, _JB_FPREGS+((F20-F0)*REGSZ)(a2) ldc1 $f21, _JB_FPREGS+((F21-F0)*REGSZ)(a2) ldc1 $f22, _JB_FPREGS+((F22-F0)*REGSZ)(a2) ldc1 $f23, _JB_FPREGS+((F23-F0)*REGSZ)(a2) ldc1 $f24, _JB_FPREGS+((F24-F0)*REGSZ)(a2) ldc1 $f25, _JB_FPREGS+((F25-F0)*REGSZ)(a2) ldc1 $f26, _JB_FPREGS+((F26-F0)*REGSZ)(a2) ldc1 $f27, _JB_FPREGS+((F27-F0)*REGSZ)(a2) ldc1 $f28, _JB_FPREGS+((F28-F0)*REGSZ)(a2) ldc1 $f29, _JB_FPREGS+((F29-F0)*REGSZ)(a2) ldc1 $f30, _JB_FPREGS+((F30-F0)*REGSZ)(a2) ldc1 $f31, _JB_FPREGS+((F31-F0)*REGSZ)(a2) #else lwc1 $f20, _JB_FPREGS+((F20-F0)*REGSZ)(a2) lwc1 $f21, _JB_FPREGS+((F21-F0)*REGSZ)(a2) lwc1 $f22, _JB_FPREGS+((F22-F0)*REGSZ)(a2) lwc1 $f23, _JB_FPREGS+((F23-F0)*REGSZ)(a2) lwc1 $f24, _JB_FPREGS+((F24-F0)*REGSZ)(a2) lwc1 $f25, _JB_FPREGS+((F25-F0)*REGSZ)(a2) lwc1 $f26, _JB_FPREGS+((F26-F0)*REGSZ)(a2) lwc1 $f27, _JB_FPREGS+((F27-F0)*REGSZ)(a2) lwc1 $f28, _JB_FPREGS+((F28-F0)*REGSZ)(a2) lwc1 $f29, _JB_FPREGS+((F29-F0)*REGSZ)(a2) lwc1 $f30, _JB_FPREGS+((F30-F0)*REGSZ)(a2) lwc1 $f31, _JB_FPREGS+((F31-F0)*REGSZ)(a2) #endif beql a4, zero, 1f li a4, 1 # only executed if branch taken. 1: j ra move v0, a4 botch: jal _libc_abort nop RESTORE_GP64 PTR_ADDU sp, FRAMESZ END_STRONG(longjmp)