584 lines
21 KiB
C++
Executable File
584 lines
21 KiB
C++
Executable File
////////////////////////////////////////////////////////////////////////
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// $Id: call_far.cc,v 1.10 2006-03-22 20:47:11 sshwarts Exp $
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/////////////////////////////////////////////////////////////////////////
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//
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// Copyright (C) 2001 MandrakeSoft S.A.
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//
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// MandrakeSoft S.A.
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// 43, rue d'Aboukir
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// 75002 Paris - France
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// http://www.linux-mandrake.com/
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// http://www.mandrakesoft.com/
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//
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// This library is free software; you can redistribute it and/or
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// modify it under the terms of the GNU Lesser General Public
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// License as published by the Free Software Foundation; either
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// version 2 of the License, or (at your option) any later version.
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//
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// This library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public
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// License along with this library; if not, write to the Free Software
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// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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//
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#define NEED_CPU_REG_SHORTCUTS 1
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#include "bochs.h"
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#include "cpu.h"
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#define LOG_THIS BX_CPU_THIS_PTR
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#if BX_SUPPORT_X86_64==0
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// Make life easier merging cpu64 & cpu code.
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#define RIP EIP
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#endif
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void BX_CPP_AttrRegparmN(3)
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BX_CPU_C::call_protected(bxInstruction_c *i, Bit16u cs_raw, bx_address disp)
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{
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bx_selector_t cs_selector;
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Bit32u dword1, dword2;
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bx_descriptor_t cs_descriptor;
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/* new cs selector must not be null, else #GP(0) */
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if ((cs_raw & 0xfffc) == 0) {
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BX_ERROR(("call_protected: CS selector null"));
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exception(BX_GP_EXCEPTION, 0, 0);
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}
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parse_selector(cs_raw, &cs_selector);
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// check new CS selector index within its descriptor limits,
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// else #GP(new CS selector)
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fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION);
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parse_descriptor(dword1, dword2, &cs_descriptor);
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// examine AR byte of selected descriptor for various legal values
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if (cs_descriptor.valid==0) {
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BX_ERROR(("call_protected: invalid CS descriptor"));
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exception(BX_GP_EXCEPTION, cs_raw & 0xfffc, 0);
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}
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if (cs_descriptor.segment) // normal segment
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{
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check_cs(&cs_descriptor, cs_raw, BX_SELECTOR_RPL(cs_raw), CPL);
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#if BX_SUPPORT_X86_64
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if (i->os64L()) {
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// push return address onto stack (CS padded to 64bits)
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push_64((Bit64u) BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value);
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push_64(RIP);
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}
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else
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#endif
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if (i->os32L()) {
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// push return address onto stack (CS padded to 32bits)
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push_32((Bit32u) BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value);
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push_32(EIP);
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}
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else {
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// push return address onto stack
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push_16(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value);
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push_16(IP);
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}
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// load code segment descriptor into CS cache
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// load CS with new code segment selector
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// set RPL of CS to CPL
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branch_far64(&cs_selector, &cs_descriptor, disp, CPL);
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return;
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}
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else { // gate & special segment
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bx_descriptor_t gate_descriptor = cs_descriptor;
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bx_selector_t gate_selector = cs_selector;
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Bit32u new_EIP;
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Bit16u dest_selector;
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Bit16u raw_tss_selector;
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bx_selector_t tss_selector;
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bx_descriptor_t tss_descriptor;
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Bit32u temp_eIP;
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// descriptor DPL must be >= CPL else #GP(gate selector)
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if (gate_descriptor.dpl < CPL) {
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BX_ERROR(("call_protected: descriptor.dpl < CPL"));
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exception(BX_GP_EXCEPTION, cs_raw & 0xfffc, 0);
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}
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// descriptor DPL must be >= gate selector RPL else #GP(gate selector)
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if (gate_descriptor.dpl < gate_selector.rpl) {
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BX_ERROR(("call_protected: descriptor.dpl < selector.rpl"));
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exception(BX_GP_EXCEPTION, cs_raw & 0xfffc, 0);
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}
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// gate descriptor must be present else #NP(gate selector)
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if (! IS_PRESENT(gate_descriptor)) {
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BX_ERROR(("call_protected: gate.p == 0"));
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exception(BX_NP_EXCEPTION, cs_raw & 0xfffc, 0);
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}
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#if BX_SUPPORT_X86_64
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if (IsLongMode()) {
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if (gate_descriptor.type != BX_386_CALL_GATE) {
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BX_ERROR(("call_protected: gate type %u unsupported in long mode", (unsigned) gate_descriptor.type));
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exception(BX_GP_EXCEPTION, cs_raw & 0xfffc, 0);
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}
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else {
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call_gate64(&gate_selector);
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return;
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}
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}
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#endif
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switch (gate_descriptor.type) {
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case BX_SYS_SEGMENT_AVAIL_286_TSS:
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case BX_SYS_SEGMENT_AVAIL_386_TSS:
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if (gate_descriptor.type==BX_SYS_SEGMENT_AVAIL_286_TSS)
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BX_DEBUG(("call_protected: 16bit available TSS"));
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else
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BX_DEBUG(("call_protected: 32bit available TSS"));
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// SWITCH_TASKS _without_ nesting to TSS
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task_switch(&gate_selector, &gate_descriptor,
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BX_TASK_FROM_CALL_OR_INT, dword1, dword2);
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// EIP must be in code seg limit, else #GP(0)
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if (EIP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) {
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BX_ERROR(("call_protected: EIP not within CS limits"));
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exception(BX_GP_EXCEPTION, 0, 0);
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}
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return;
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case BX_TASK_GATE:
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// examine selector to TSS, given in Task Gate descriptor
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// must specify global in the local/global bit else #TS(TSS selector)
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raw_tss_selector = gate_descriptor.u.taskgate.tss_selector;
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parse_selector(raw_tss_selector, &tss_selector);
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if (tss_selector.ti) {
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BX_ERROR(("call_protected: tss_selector.ti=1"));
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exception(BX_GP_EXCEPTION, raw_tss_selector & 0xfffc, 0);
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}
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// index must be within GDT limits else #TS(TSS selector)
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fetch_raw_descriptor(&tss_selector, &dword1, &dword2, BX_GP_EXCEPTION);
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parse_descriptor(dword1, dword2, &tss_descriptor);
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// descriptor AR byte must specify available TSS
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// else #GP(TSS selector)
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if (tss_descriptor.valid==0 || tss_descriptor.segment) {
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BX_ERROR(("call_protected: TSS selector points to bad TSS"));
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exception(BX_GP_EXCEPTION, raw_tss_selector & 0xfffc, 0);
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}
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if (tss_descriptor.type!=9 && tss_descriptor.type!=1) {
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BX_ERROR(("call_protected: TSS selector points to bad TSS"));
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exception(BX_GP_EXCEPTION, raw_tss_selector & 0xfffc, 0);
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}
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// task state segment must be present, else #NP(tss selector)
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if (! IS_PRESENT(tss_descriptor)) {
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BX_ERROR(("call_protected: task descriptor.p == 0"));
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exception(BX_NP_EXCEPTION, raw_tss_selector & 0xfffc, 0);
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}
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// SWITCH_TASKS without nesting to TSS
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task_switch(&tss_selector, &tss_descriptor,
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BX_TASK_FROM_CALL_OR_INT, dword1, dword2);
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// EIP must be within code segment limit, else #TS(0)
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if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.d_b)
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temp_eIP = EIP;
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else
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temp_eIP = IP;
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if (temp_eIP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled)
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{
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BX_ERROR(("call_protected: EIP > CS.limit"));
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exception(BX_GP_EXCEPTION, 0, 0);
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}
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return;
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case BX_286_CALL_GATE:
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case BX_386_CALL_GATE:
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// examine code segment selector in call gate descriptor
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if (gate_descriptor.type == BX_286_CALL_GATE) {
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BX_DEBUG(("call_protected: CALL 16bit call gate"));
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dest_selector = gate_descriptor.u.gate286.dest_selector;
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new_EIP = gate_descriptor.u.gate286.dest_offset;
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}
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else {
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BX_DEBUG(("call_protected: CALL 32bit call gate"));
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dest_selector = gate_descriptor.u.gate386.dest_selector;
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new_EIP = gate_descriptor.u.gate386.dest_offset;
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}
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// selector must not be null else #GP(0)
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if ( (dest_selector & 0xfffc) == 0 ) {
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BX_ERROR(("call_protected: selector in gate null"));
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exception(BX_GP_EXCEPTION, 0, 0);
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}
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parse_selector(dest_selector, &cs_selector);
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// selector must be within its descriptor table limits,
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// else #GP(code segment selector)
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fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION);
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parse_descriptor(dword1, dword2, &cs_descriptor);
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// AR byte of selected descriptor must indicate code segment,
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// else #GP(code segment selector)
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// DPL of selected descriptor must be <= CPL,
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// else #GP(code segment selector)
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if (cs_descriptor.valid==0 || cs_descriptor.segment==0 ||
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cs_descriptor.u.segment.executable==0 ||
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cs_descriptor.dpl > CPL)
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{
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BX_ERROR(("call_protected: selected descriptor is not code"));
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exception(BX_GP_EXCEPTION, dest_selector & 0xfffc, 0);
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}
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// code segment must be present else #NP(selector)
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if (! IS_PRESENT(cs_descriptor)) {
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BX_ERROR(("call_protected: code segment not present !"));
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exception(BX_NP_EXCEPTION, dest_selector & 0xfffc, 0);
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}
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// CALL GATE TO MORE PRIVILEGE
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// if non-conforming code segment and DPL < CPL then
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if ( (cs_descriptor.u.segment.c_ed==0) &&
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(cs_descriptor.dpl < CPL) )
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{
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Bit16u SS_for_cpl_x;
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Bit32u ESP_for_cpl_x;
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bx_selector_t ss_selector;
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bx_descriptor_t ss_descriptor;
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unsigned room_needed, param_count;
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Bit16u return_SS, return_CS;
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Bit32u return_ESP, return_EIP;
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Bit32u return_ss_base;
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Bit16u parameter_word[32];
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Bit32u parameter_dword[32];
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Bit32u temp_ESP;
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BX_DEBUG(("CALL GATE TO MORE PRIVILEGE LEVEL"));
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// get new SS selector for new privilege level from TSS
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get_SS_ESP_from_TSS(cs_descriptor.dpl, &SS_for_cpl_x, &ESP_for_cpl_x);
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// check selector & descriptor for new SS:
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// selector must not be null, else #TS(0)
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if ( (SS_for_cpl_x & 0xfffc) == 0 ) {
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BX_ERROR(("call_protected: new SS null"));
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exception(BX_TS_EXCEPTION, 0, 0);
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}
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// selector index must be within its descriptor table limits,
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// else #TS(SS selector)
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parse_selector(SS_for_cpl_x, &ss_selector);
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fetch_raw_descriptor(&ss_selector, &dword1, &dword2, BX_TS_EXCEPTION);
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parse_descriptor(dword1, dword2, &ss_descriptor);
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// selector's RPL must equal DPL of code segment,
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// else #TS(SS selector)
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if (ss_selector.rpl != cs_descriptor.dpl) {
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BX_DEBUG(("call_protected: SS selector.rpl != CS descr.dpl"));
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exception(BX_TS_EXCEPTION, SS_for_cpl_x & 0xfffc, 0);
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}
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// stack segment DPL must equal DPL of code segment,
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// else #TS(SS selector)
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if (ss_descriptor.dpl != cs_descriptor.dpl) {
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BX_ERROR(("call_protected: SS descr.rpl != CS descr.dpl"));
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exception(BX_TS_EXCEPTION, SS_for_cpl_x & 0xfffc, 0);
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}
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// descriptor must indicate writable data segment,
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// else #TS(SS selector)
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if (ss_descriptor.valid==0 || ss_descriptor.segment==0 ||
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ss_descriptor.u.segment.executable ||
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ss_descriptor.u.segment.r_w==0)
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{
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BX_ERROR(("call_protected: ss descriptor not writable data seg"));
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exception(BX_TS_EXCEPTION, SS_for_cpl_x & 0xfffc, 0);
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}
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// segment must be present, else #SS(SS selector)
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if (! IS_PRESENT(ss_descriptor)) {
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BX_ERROR(("call_protected: ss descriptor not present"));
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exception(BX_SS_EXCEPTION, SS_for_cpl_x & 0xfffc, 0);
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}
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if (cs_descriptor.u.segment.d_b)
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// new stack must have room for parameters plus 16 bytes
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room_needed = 16;
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else
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// new stack must have room for parameters plus 8 bytes
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room_needed = 8;
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if (gate_descriptor.type==BX_286_CALL_GATE) {
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// get word count from call gate, mask to 5 bits
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param_count = gate_descriptor.u.gate286.word_count & 0x1f;
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room_needed += param_count*2;
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}
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else {
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// get word count from call gate, mask to 5 bits
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param_count = gate_descriptor.u.gate386.dword_count & 0x1f;
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room_needed += param_count*4;
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}
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// new stack must have room for parameters plus return info
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// else #SS(SS selector)
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if (!can_push(&ss_descriptor, ESP_for_cpl_x, room_needed)) {
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BX_INFO(("call_protected: stack doesn't have room"));
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exception(BX_SS_EXCEPTION, SS_for_cpl_x & 0xfffc, 0);
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}
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// new eIP must be in code segment limit else #GP(0)
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if (new_EIP > cs_descriptor.u.segment.limit_scaled) {
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BX_ERROR(("call_protected: EIP not within CS limits"));
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exception(BX_GP_EXCEPTION, 0, 0);
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}
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// save return SS:eSP to be pushed on new stack
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return_SS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value;
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if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b)
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return_ESP = ESP;
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else
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return_ESP = SP;
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return_ss_base = BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_SS);
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// save return CS:eIP to be pushed on new stack
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return_CS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value;
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if (cs_descriptor.u.segment.d_b)
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return_EIP = EIP;
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else
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return_EIP = IP;
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if (gate_descriptor.type==BX_286_CALL_GATE) {
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for (unsigned i=0; i<param_count; i++) {
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access_linear(return_ss_base + return_ESP + i*2,
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2, 0, BX_READ, ¶meter_word[i]);
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}
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}
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else {
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for (unsigned i=0; i<param_count; i++) {
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access_linear(return_ss_base + return_ESP + i*4,
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4, 0, BX_READ, ¶meter_dword[i]);
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}
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}
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// Help for OS/2
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BX_CPU_THIS_PTR except_chk = 1;
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BX_CPU_THIS_PTR except_cs = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS];
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BX_CPU_THIS_PTR except_ss = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS];
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/* load new SS:SP value from TSS */
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/* load SS descriptor */
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load_ss(&ss_selector, &ss_descriptor, ss_descriptor.dpl);
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if (ss_descriptor.u.segment.d_b)
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ESP = ESP_for_cpl_x;
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else
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SP = (Bit16u) ESP_for_cpl_x;
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/* load new CS:IP value from gate */
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/* load CS descriptor */
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/* set CPL to stack segment DPL */
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/* set RPL of CS to CPL */
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load_cs(&cs_selector, &cs_descriptor, cs_descriptor.dpl);
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EIP = new_EIP;
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// push pointer of old stack onto new stack
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if (gate_descriptor.type==BX_386_CALL_GATE) {
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push_32(return_SS);
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push_32(return_ESP);
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}
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else {
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push_16(return_SS);
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push_16((Bit16u) return_ESP);
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}
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/* get word count from call gate, mask to 5 bits */
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/* copy parameters from old stack onto new stack */
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if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b)
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temp_ESP = ESP;
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else
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temp_ESP = SP;
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if (gate_descriptor.type==BX_286_CALL_GATE) {
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for (unsigned i=param_count; i>0; i--) {
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push_16(parameter_word[i-1]);
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}
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// push return address onto new stack
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push_16(return_CS);
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push_16((Bit16u) return_EIP);
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}
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else {
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for (unsigned i=param_count; i>0; i--) {
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push_32(parameter_dword[i-1]);
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}
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// push return address onto new stack
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push_32(return_CS);
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push_32(return_EIP);
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}
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// Help for OS/2
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BX_CPU_THIS_PTR except_chk = 0;
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}
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else // CALL GATE TO SAME PRIVILEGE
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{
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BX_DEBUG(("CALL GATE TO SAME PRIVILEGE"));
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if (gate_descriptor.type == BX_386_CALL_GATE) {
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// call gate 32bit, push return address onto stack
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push_32(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value);
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push_32(EIP);
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}
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else {
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// call gate 16bit, push return address onto stack
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push_16(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value);
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push_16(IP);
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}
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// load CS:EIP from gate
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// load code segment descriptor into CS register
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// set RPL of CS to CPL
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branch_far32(&cs_selector, &cs_descriptor, new_EIP, CPL);
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}
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return;
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default:
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BX_ERROR(("call_protected: gate type %u unsupported", (unsigned) cs_descriptor.type));
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exception(BX_GP_EXCEPTION, cs_raw & 0xfffc, 0);
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}
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}
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}
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|
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|
#if BX_SUPPORT_X86_64
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void BX_CPP_AttrRegparmN(3)
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BX_CPU_C::call_gate64(bx_selector_t *gate_selector)
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|
{
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|
bx_selector_t cs_selector;
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|
Bit32u dword1, dword2, dword3;
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|
bx_descriptor_t cs_descriptor;
|
|
bx_descriptor_t gate_descriptor;
|
|
|
|
// examine code segment selector in call gate descriptor
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|
BX_DEBUG(("call_gate64: CALL 64bit call gate"));
|
|
|
|
fetch_raw_descriptor64(gate_selector, &dword1, &dword2, &dword3, BX_GP_EXCEPTION);
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|
parse_descriptor(dword1, dword2, &gate_descriptor);
|
|
|
|
Bit16u dest_selector = gate_descriptor.u.gate386.dest_selector;
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|
// selector must not be null else #GP(0)
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|
if ( (dest_selector & 0xfffc) == 0 ) {
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|
BX_ERROR(("call_gate64: selector in gate null"));
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|
exception(BX_GP_EXCEPTION, 0, 0);
|
|
}
|
|
|
|
parse_selector(dest_selector, &cs_selector);
|
|
// selector must be within its descriptor table limits,
|
|
// else #GP(code segment selector)
|
|
fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION);
|
|
parse_descriptor(dword1, dword2, &cs_descriptor);
|
|
|
|
// find the RIP in the gate_descriptor
|
|
Bit64u new_RIP = gate_descriptor.u.gate386.dest_offset;
|
|
new_RIP |= ((Bit64u)dword3 << 32);
|
|
|
|
// AR byte of selected descriptor must indicate code segment,
|
|
// else #GP(code segment selector)
|
|
// DPL of selected descriptor must be <= CPL,
|
|
// else #GP(code segment selector)
|
|
if (cs_descriptor.valid==0 || cs_descriptor.segment==0 ||
|
|
cs_descriptor.u.segment.executable==0 ||
|
|
cs_descriptor.dpl > CPL)
|
|
{
|
|
BX_ERROR(("call_gate64: selected descriptor is not code"));
|
|
exception(BX_GP_EXCEPTION, dest_selector & 0xfffc, 0);
|
|
}
|
|
|
|
// In long mode, only 64-bit call gates are allowed, and they must point
|
|
// to 64-bit code segments, else #GP(selector)
|
|
if (! IS_LONG64_SEGMENT(cs_descriptor) || cs_descriptor.u.segment.d_b)
|
|
{
|
|
BX_ERROR(("call_gate64: not 64-bit code segment in call gate 64"));
|
|
exception(BX_GP_EXCEPTION, dest_selector & 0xfffc, 0);
|
|
}
|
|
|
|
// code segment must be present else #NP(selector)
|
|
if (! IS_PRESENT(cs_descriptor)) {
|
|
BX_ERROR(("call_gate64: code segment not present !"));
|
|
exception(BX_NP_EXCEPTION, dest_selector & 0xfffc, 0);
|
|
}
|
|
|
|
Bit16u old_CS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value;
|
|
Bit64u old_RIP = RIP;
|
|
|
|
// CALL GATE TO MORE PRIVILEGE
|
|
// if non-conforming code segment and DPL < CPL then
|
|
if ( (cs_descriptor.u.segment.c_ed==0) &&
|
|
(cs_descriptor.dpl < CPL) )
|
|
{
|
|
Bit64u RSP_for_cpl_x;
|
|
|
|
BX_DEBUG(("CALL GATE TO MORE PRIVILEGE LEVEL"));
|
|
|
|
// get new RSP for new privilege level from TSS
|
|
get_RSP_from_TSS(cs_descriptor.dpl, &RSP_for_cpl_x);
|
|
|
|
if (! IsCanonical(RSP_for_cpl_x)) {
|
|
BX_ERROR(("call_gate64: canonical address failure %08x%08x",
|
|
(Bit32u)(RSP_for_cpl_x >> 32), (Bit32u)(RSP_for_cpl_x & 0xffffffff)));
|
|
exception(BX_GP_EXCEPTION, 0, 0);
|
|
}
|
|
|
|
Bit16u old_SS = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value;
|
|
Bit64u old_RSP = RSP;
|
|
|
|
bx_selector_t ss_selector;
|
|
bx_descriptor_t ss_descriptor;
|
|
|
|
// set up a null descriptor
|
|
parse_selector(0, &ss_selector);
|
|
parse_descriptor(0, 0, &ss_descriptor);
|
|
|
|
// load CS:RIP (guaranteed to be in 64 bit mode)
|
|
branch_far64(&cs_selector, &cs_descriptor, new_RIP, cs_descriptor.dpl);
|
|
|
|
// set up null SS descriptor
|
|
load_ss(&ss_selector, &ss_descriptor, cs_descriptor.dpl);
|
|
|
|
RSP = RSP_for_cpl_x;
|
|
|
|
// push old stack long pointer onto new stack
|
|
push_64(old_SS);
|
|
push_64(old_RSP);
|
|
// push long pointer to return address onto new stack
|
|
push_64(old_CS);
|
|
push_64(old_RIP);
|
|
}
|
|
else
|
|
{
|
|
BX_DEBUG(("CALL GATE TO SAME PRIVILEGE"));
|
|
|
|
// make sure that push CS:RIP will not fail
|
|
if (! IsCanonical(RSP)) {
|
|
BX_ERROR(("call_gate64: canonical address failure %08x%08x",
|
|
(Bit32u)(RSP >> 32), (Bit32u)(RSP & 0xffffffff)));
|
|
exception(BX_GP_EXCEPTION, 0, 0);
|
|
}
|
|
|
|
// load CS:RIP (guaranteed to be in 64 bit mode)
|
|
branch_far64(&cs_selector, &cs_descriptor, new_RIP, CPL);
|
|
|
|
// push return address onto stack
|
|
push_64(old_CS);
|
|
push_64(old_RIP);
|
|
}
|
|
}
|
|
#endif
|