/* prmci3li.c: PROTECTION MUTATOR CONTEXT INTEL 386 (LINUX)
*
* $Id: //info.ravenbrook.com/project/mps/version/1.109/code/prmci3li.c#1 $
* Copyright (c) 2001 Ravenbrook Limited. See end of file for license.
*
* .purpose: This module implements the part of the protection module
* that decodes the MutatorFaultContext.
*
*
* SOURCES
*
* .source.i486: Intel486 Microprocessor Family Programmer's
* Reference Manual
*
* .source.linux.kernel: Linux kernel source files.
*
*
* ASSUMPTIONS
*
* .assume.regref: The resisters in the context can be modified by
* storing into an MRef pointer.
*/
/* prmcli.h will include mpm.h after defining open sesame magic */
#include "prmcli.h"
#include "prmci3.h"
SRCID(prmci3li, "$Id: //info.ravenbrook.com/project/mps/version/1.109/code/prmci3li.c#1 $");
/* Prmci3AddressHoldingReg -- return an address of a register in a context */
MRef Prmci3AddressHoldingReg(MutatorFaultContext context, unsigned int regnum)
{
struct sigcontext *scp;
AVER(regnum <= 7);
AVER(regnum >= 0);
scp = context->scp;
/* .source.i486 */
/* .assume.regref */
switch (regnum) {
case 0: return (MRef)&scp->eax;
case 1: return (MRef)&scp->ecx;
case 2: return (MRef)&scp->edx;
case 3: return (MRef)&scp->ebx;
case 4: return (MRef)&scp->esp;
case 5: return (MRef)&scp->ebp;
case 6: return (MRef)&scp->esi;
case 7: return (MRef)&scp->edi;
}
NOTREACHED;
return (MRef)NULL; /* Avoids compiler warning. */
}
/* Prmci3DecodeFaultContext -- decode fault to find faulting address and IP */
void Prmci3DecodeFaultContext(MRef *faultmemReturn,
Byte **insvecReturn,
MutatorFaultContext context)
{
struct sigcontext *scp;
scp = context->scp;
/* Assert that this is a page fault exception. The computation of */
/* faultmem depends on this. See .source.i486 (9.9.14). */
AVER(scp->trapno == 14);
/* cr2 contains the address which caused the fault. */
/* See .source.i486 (9.9.14) and */
/* .source.linux.kernel (linux/arch/i386/mm/fault.c). */
*faultmemReturn = (MRef)scp->cr2;
*insvecReturn = (Byte*)scp->eip;
}
/* Prmci3StepOverIns -- modify context to step over instruction */
void Prmci3StepOverIns(MutatorFaultContext context, Size inslen)
{
context->scp->eip += (unsigned long)inslen;
}
/* C. COPYRIGHT AND LICENSE
*
* Copyright (C) 2001-2002 Ravenbrook Limited <http://www.ravenbrook.com/>.
* All rights reserved. This is an open source license. Contact
* Ravenbrook for commercial licensing options.
*
* 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. Redistributions in any form must be accompanied by information on how
* to obtain complete source code for this software and any accompanying
* software that uses this software. The source code must either be
* included in the distribution or be available for no more than the cost
* of distribution plus a nominal fee, and must be freely redistributable
* under reasonable conditions. For an executable file, complete source
* code means the source code for all modules it contains. It does not
* include source code for modules or files that typically accompany the
* major components of the operating system on which the executable file
* runs.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
* PURPOSE, OR NON-INFRINGEMENT, ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDERS AND CONTRIBUTORS 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.
*/