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linux_ptrace.c revision 1.3
      1 /*	$NetBSD: linux_ptrace.c,v 1.3 1999/12/16 15:11:19 tron Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1999 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Matthias Scheler.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  * 3. All advertising materials mentioning features or use of this software
     19  *    must display the following acknowledgement:
     20  *	This product includes software developed by the NetBSD
     21  *	Foundation, Inc. and its contributors.
     22  * 4. Neither the name of The NetBSD Foundation nor the names of its
     23  *    contributors may be used to endorse or promote products derived
     24  *    from this software without specific prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     36  * POSSIBILITY OF SUCH DAMAGE.
     37  */
     38 
     39 #include <sys/types.h>
     40 #include <sys/param.h>
     41 #include <sys/mount.h>
     42 #include <sys/proc.h>
     43 #include <sys/ptrace.h>
     44 #include <sys/systm.h>
     45 #include <sys/syscallargs.h>
     46 
     47 #include <machine/reg.h>
     48 
     49 #include <compat/linux/common/linux_types.h>
     50 #include <compat/linux/common/linux_ptrace.h>
     51 #include <compat/linux/common/linux_signal.h>
     52 
     53 #include <compat/linux/common/linux_util.h>
     54 #include <compat/linux/common/linux_machdep.h>
     55 
     56 #include <compat/linux/linux_syscallargs.h>
     57 
     58 #define LINUX_PTRACE_GETREGS		12
     59 #define LINUX_PTRACE_SETREGS		13
     60 #define LINUX_PTRACE_GETFPREGS		14
     61 #define LINUX_PTRACE_SETFPREGS		15
     62 
     63 struct linux_reg {
     64 	long ebx;
     65 	long ecx;
     66 	long edx;
     67 	long esi;
     68 	long edi;
     69 	long ebp;
     70 	long eax;
     71 	int  xds;
     72 	int  xes;
     73 	long orig_eax;
     74 	long eip;
     75 	int  xcs;
     76 	long eflags;
     77 	long esp;
     78 	int  xss;
     79 };
     80 
     81 #define ISSET(t, f)	((t) & (f))
     82 
     83 int
     84 linux_sys_ptrace_arch(p, v, retval)
     85 	struct proc *p;
     86 	void *v;
     87 	register_t *retval;
     88 {
     89 	struct linux_sys_ptrace_args /* {
     90 		syscallarg(int) request;
     91 		syscallarg(int) pid;
     92 		syscallarg(int) addr;
     93 		syscallarg(int) data;
     94 	} */ *uap = v;
     95 	int request, error;
     96 	struct proc *t;				/* target process */
     97 	struct reg regs;
     98 	struct linux_reg linux_regs;
     99 
    100 	request = SCARG(uap, request);
    101 
    102 	if ((request != LINUX_PTRACE_GETREGS) &&
    103 	    (request != LINUX_PTRACE_SETREGS) &&
    104 	    (request != LINUX_PTRACE_GETFPREGS) &&
    105 	    (request != LINUX_PTRACE_SETFPREGS))
    106 		return EIO;
    107 
    108 	/* Find the process we're supposed to be operating on. */
    109 	if ((t = pfind(SCARG(uap, pid))) == NULL)
    110 		return ESRCH;
    111 
    112 	/*
    113 	 * You can't do what you want to the process if:
    114 	 *	(1) It's not being traced at all,
    115 	 */
    116 	if (!ISSET(t->p_flag, P_TRACED))
    117 		return EPERM;
    118 
    119 	/*
    120 	 *	(2) it's being traced by procfs (which has
    121 	 *	    different signal delivery semantics),
    122 	 */
    123 	if (ISSET(t->p_flag, P_FSTRACE))
    124 		return EBUSY;
    125 
    126 	/*
    127 	 *	(3) it's not being traced by _you_, or
    128 	 */
    129 	if (t->p_pptr != p)
    130 		return EBUSY;
    131 
    132 	/*
    133 	 *	(4) it's not currently stopped.
    134 	 */
    135 	if (t->p_stat != SSTOP || !ISSET(t->p_flag, P_WAITED))
    136 		return EBUSY;
    137 
    138 	*retval = 0;
    139 
    140 	switch (request) {
    141 	case  LINUX_PTRACE_GETREGS:
    142 		error = process_read_regs(t, &regs);
    143 		if (error != 0)
    144 			return error;
    145 
    146 		linux_regs.ebx = regs.r_ebx;
    147 		linux_regs.ecx = regs.r_ecx;
    148 		linux_regs.edx = regs.r_edx;
    149 		linux_regs.esi = regs.r_esi;
    150 		linux_regs.edi = regs.r_edi;
    151 		linux_regs.ebp = regs.r_ebp;
    152 		linux_regs.eax = regs.r_eax;
    153 		linux_regs.xds = regs.r_ds;
    154 		linux_regs.xes = regs.r_es;
    155 		linux_regs.orig_eax = regs.r_eax; /* XXX is this correct? */
    156 		linux_regs.eip = regs.r_eip;
    157 		linux_regs.xcs = regs.r_cs;
    158 		linux_regs.eflags = regs.r_eflags;
    159 		linux_regs.esp = regs.r_esp;
    160 		linux_regs.xss = regs.r_ss;
    161 
    162 		return copyout(&linux_regs, (caddr_t)SCARG(uap, data),
    163 		    sizeof(struct linux_reg));
    164 	case  LINUX_PTRACE_SETREGS:
    165 		error = copyin((caddr_t)SCARG(uap, data), &linux_regs,
    166 		    sizeof(struct linux_reg));
    167 		if (error != 0)
    168 			return error;
    169 
    170 		regs.r_ebx = linux_regs.ebx;
    171 		regs.r_ecx = linux_regs.ecx;
    172 		regs.r_edx = linux_regs.edx;
    173 		regs.r_esi = linux_regs.esi;
    174 		regs.r_edi = linux_regs.edi;
    175 		regs.r_ebp = linux_regs.ebp;
    176 		regs.r_eax = linux_regs.eax;
    177 		regs.r_ds = linux_regs.xds;
    178 		regs.r_es = linux_regs.xes;
    179 		regs.r_eip = linux_regs.eip;
    180 		regs.r_cs = linux_regs.xcs;
    181 		regs.r_eflags = linux_regs.eflags;
    182 		regs.r_esp = linux_regs.esp;
    183 		regs.r_ss = linux_regs.xss;
    184 
    185 		return process_write_regs(t, &regs);
    186 	}
    187 
    188 	return EIO;
    189 }
    190