perso
/
cos2000v1
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

feat: ajout des mbs lors du debug, ajustement pour FLAT UNREAL MODE

This commit is contained in:
Nicolas Hordé 2019-07-17 14:09:41 +02:00
parent dc0184f27d
commit 06eb38cad0
1 changed files with 106 additions and 47 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

153
debug/gdb_init_real_mode.txt
View File

@ -1,4 +1,5 @@
# Special mode for GDB that allows to debug/disassemble REAL MODE x86 code # Modified by Nicolas Horde
# Special mode for GDB that allows to debug/disassemble FLAT OR UNREAL MODE x86 code
# #
# It has been designed to be used with QEMU or BOCHS gdb-stub # It has been designed to be used with QEMU or BOCHS gdb-stub
# #
@ -70,53 +71,93 @@ Get address of interruption
end end
define compute_regs define compute_regs
set $rax = ((unsigned long)$eax & 0xFFFF) set $rax = ((unsigned long)$eax & 0xFFFFFFFF)
set $rbx = ((unsigned long)$ebx & 0xFFFF) set $rbx = ((unsigned long)$ebx & 0xFFFFFFFF)
set $rcx = ((unsigned long)$ecx & 0xFFFF) set $rcx = ((unsigned long)$ecx & 0xFFFFFFFF)
set $rdx = ((unsigned long)$edx & 0xFFFF) set $rdx = ((unsigned long)$edx & 0xFFFFFFFF)
set $rsi = ((unsigned long)$esi & 0xFFFF) set $rsi = ((unsigned long)$esi & 0xFFFFFFFF)
set $rdi = ((unsigned long)$edi & 0xFFFF) set $rdi = ((unsigned long)$edi & 0xFFFFFFFF)
set $rbp = ((unsigned long)$ebp & 0xFFFF) set $rbp = ((unsigned long)$ebp & 0xFFFFFFFF)
set $rsp = ((unsigned long)$esp & 0xFFFF) set $rsp = ((unsigned long)$esp & 0xFFFFFFFF)
set $rcs = ((unsigned long)$cs & 0xFFFF) set $rcs = ((unsigned long)$cs & 0xFFFF)
set $rds = ((unsigned long)$ds & 0xFFFF) set $rds = ((unsigned long)$ds & 0xFFFF)
set $res = ((unsigned long)$es & 0xFFFF) set $res = ((unsigned long)$es & 0xFFFF)
set $rss = ((unsigned long)$ss & 0xFFFF) set $rss = ((unsigned long)$ss & 0xFFFF)
set $rip = ((((unsigned long)$cs & 0xFFFF) << 4) + ((unsigned long)$eip & 0xFFFF)) & $ADDRESS_MASK set $rfs = ((unsigned long)$es & 0xFFFF)
set $r_ss_sp = ((((unsigned long)$ss & 0xFFFF) << 4) + ((unsigned long)$esp & 0xFFFF)) & $ADDRESS_MASK set $rgs = ((unsigned long)$ss & 0xFFFF)
set $r_ss_bp = ((((unsigned long)$ss & 0xFFFF) << 4) + ((unsigned long)$ebp & 0xFFFF)) & $ADDRESS_MASK set $rip = ((((unsigned long)$cs & 0xFFFF) << 4) + ((unsigned long)$eip & 0xFFFFFFFF)) & $ADDRESS_MASK
set $r_ss_sp = ((((unsigned long)$ss & 0xFFFF) << 4) + ((unsigned long)$esp & 0xFFFFFFFF)) & $ADDRESS_MASK
set $r_ss_bp = ((((unsigned long)$ss & 0xFFFF) << 4) + ((unsigned long)$ebp & 0xFFFFFFFF)) & $ADDRESS_MASK
end end
define print_regs define print_regs
printf "AX: %04X BX: %04X ", $rax, $rbx printf "EAX: %08X EBX: %08X ", $rax, $rbx
printf "CX: %04X DX: %04X\n", $rcx, $rdx printf "ECX: %08X EDX: %08X\n", $rcx, $rdx
printf "SI: %04X DI: %04X ", $rsi, $rdi printf "ESI: %08X EDI: %08X ", $rsi, $rdi
printf "SP: %04X BP: %04X\n", $rsp, $rbp printf "ESP: %08X EBP: %08X\n", $rsp, $rbp
printf "CS: %04X DS: %04X ", $rcs, $rds printf " CS: %04X DS: %04X ", $rcs, $rds
printf "ES: %04X SS: %04X\n", $res, $rss printf " ES: %04X SS: %04X ", $res, $rss
printf " FS: %04X GS: %04X ", $rfs, $rgs
printf "\n" printf "\n"
printf "IP: %04X EIP:%08X\n", ((unsigned short)$eip & 0xFFFF), $eip printf "CS:IP: %04X:%08X (0x%05X)\n", $rcs, ((unsigned long)$eip), $rip
printf "CS:IP: %04X:%04X (0x%05X)\n", $rcs, ((unsigned short)$eip & 0xFFFF), $rip printf "SS:SP: %04X:%08X (0x%05X)\n", $rss, $rsp, $r_ss_sp
printf "SS:SP: %04X:%04X (0x%05X)\n", $rss, $rsp, $r_ss_sp printf "SS:BP: %04X:%08X (0x%05X)\n", $rss, $rbp, $r_ss_bp
printf "SS:BP: %04X:%04X (0x%05X)\n", $rss, $rbp, $r_ss_bp
end end
document print_regs document print_regs
Print CPU registers Print CPU registers
end end
define print_eflags define print_eflags
printf "OF <%d> DF <%d> IF <%d> TF <%d>",\ printf "EFLAGS: %08X [",$eflags
(($eflags >> 0xB) & 1), (($eflags >> 0xA) & 1), \ if ($eflags & 1)
(($eflags >> 9) & 1), (($eflags >> 8) & 1) printf "C"
printf " SF <%d> ZF <%d> AF <%d> PF <%d> CF <%d>\n",\ else
(($eflags >> 7) & 1), (($eflags >> 6) & 1),\ printf "-"
(($eflags >> 4) & 1), (($eflags >> 2) & 1), ($eflags & 1) end
printf "ID <%d> VIP <%d> VIF <%d> AC <%d>",\ printf "-"
(($eflags >> 0x15) & 1), (($eflags >> 0x14) & 1), \ if (($eflags >> 2) & 1)
(($eflags >> 0x13) & 1), (($eflags >> 0x12) & 1) printf "P"
printf " VM <%d> RF <%d> NT <%d> IOPL <%d>\n",\ else
(($eflags >> 0x11) & 1), (($eflags >> 0x10) & 1),\ printf "-"
(($eflags >> 0xE) & 1), (($eflags >> 0xC) & 3) end
printf "-"
if (($eflags >> 4) & 1)
printf "A"
else
printf "-"
end
printf "-"
if (($eflags >> 6) & 1)
printf "Z"
else
printf "-"
end
if (($eflags >> 7) & 1)
printf "S"
else
printf "-"
end
if (($eflags >> 8) & 1)
printf "T"
else
printf "-"
if (($eflags >> 9) & 1)
printf "I"
else
printf "-"
end
if (($eflags >> 0xA) & 1)
printf "D"
else
printf "-"
end
if (($eflags >> 0xB) & 1)
printf "O"
else
printf "-"
end
printf "]\n"
end
end end
document print_eflags document print_eflags
Print eflags register. Print eflags register.
@ -161,13 +202,12 @@ define print_data
if ($argc > 0) if ($argc > 0)
set $seg = $arg0 set $seg = $arg0
set $off = $arg1 set $off = $arg1
set $raddr = ($arg0 << 16) + $arg1
set $maddr = ($arg0 << 4) + $arg1 set $maddr = ($arg0 << 4) + $arg1
set $w = 16 set $w = 16
set $i = (int)0 set $i = (int)0
while ($i < 4) while ($i < 2)
printf "%08X: ", ($raddr + $i * $w) printf "%08X: ", ($maddr + $i * $w)
set $j = (int)0 set $j = (int)0
while ($j < $w) while ($j < $w)
printf "%02X ", *(unsigned char*)($maddr + $i * $w + $j) printf "%02X ", *(unsigned char*)($maddr + $i * $w + $j)
@ -192,22 +232,40 @@ define print_data
end end
end end
# affiche les mb
define print_mb
set $mem=1280
set $verif = *(unsigned char*)($mem)
set $verif2 = *(unsigned char*)($mem+1)
set $stop = 0x01
while ($verif == 0x4E && $verif2 == 0x48 && $stop == 0x01)
set $stop = *(unsigned char*)($mem+2)
set $size = *(unsigned short*)($mem+6)
set $name = (unsigned char*)($mem+8)
printf "%s:%4X:%4X\n",$name,$mem,$size
set $mem=$mem+$size
set $verif = *(unsigned char*)($mem)
set $verif2 = *(unsigned char*)($mem+1)
end
end
define context define context
printf "---------------------------[ STACK ]---\n" printf "---------------------------[ STACK ]---------------------------\n"
_dump_memw $r_ss_sp 8 _dump_memw $r_ss_sp 8
printf "\n" printf "\n"
set $_a = $r_ss_sp + 16 set $_a = $r_ss_sp + 16
_dump_memw $_a 8 _dump_memw $_a 8
printf "\n" printf "\n"
printf "---------------------------[ DS:SI ]---\n" printf "---------------------------[ DS:ESI ]---------------------------\n"
print_data $ds $rsi print_data $ds $rsi
printf "---------------------------[ ES:DI ]---\n" printf "---------------------------[ ES:EDI ]---------------------------\n"
print_data $es $rdi print_data $es $rdi
printf "----------------------------[ CPU ]---------------------------\n"
printf "----------------------------[ CPU ]----\n"
print_regs print_regs
print_eflags print_eflags
printf "---------------------------[ CODE ]----\n" printf "----------------------------[ MB ]---------------------------\n"
print_mb
printf "---------------------------[ CODE ]---------------------------\n"
set $_code_size = $CODE_SIZE set $_code_size = $CODE_SIZE
@ -271,7 +329,7 @@ document break_int_if_ax
Install a breakpoint on INT N only if AX is equal to the expected value Install a breakpoint on INT N only if AX is equal to the expected value
end end
define stepo define so
## we know that an opcode starting by 0xE8 has a fixed length ## we know that an opcode starting by 0xE8 has a fixed length
## for the 0xFF opcodes, we can enumerate what is possible to have ## for the 0xFF opcodes, we can enumerate what is possible to have
@ -347,16 +405,17 @@ define stepo
# if we have found a call to bypass we set a temporary breakpoint on next instruction and continue # if we have found a call to bypass we set a temporary breakpoint on next instruction and continue
if ($noffset != 0) if ($noffset != 0)
set $_nextaddress = $eip + $offset + $noffset set $_nextaddress = $eip + $offset + $noffset+$cs*16
printf "Setting BP to %04X\n", $_nextaddress printf "Setting BP to %04X\n", $_nextaddress
tbreak *$_nextaddress break *$_nextaddress
continue continue
cl *$_nextaddress
# else we just single step # else we just single step
else else
nexti nexti
end end
end end
document stepo document so
Step over calls Step over calls
This function will set a temporary breakpoint on next instruction after the call so the call will be bypassed This function will set a temporary breakpoint on next instruction after the call so the call will be bypassed
You can safely use it instead nexti since it will single step code if it's not a call instruction (unless you want to go into the call function) You can safely use it instead nexti since it will single step code if it's not a call instruction (unless you want to go into the call function)