# INSTALL INSTRUCTIONS: save as ~/.gdbinit # # DESCRIPTION: A user-friendly gdb configuration file, for x86/x86_64 and ARM platforms. # # REVISION : 8.0.4 (08/05/2013) # # CONTRIBUTORS: mammon_, elaine, pusillus, mong, zhang le, l0kit, # truthix the cyberpunk, fG!, gln # # FEEDBACK: http://reverse.put.as - reverser@put.as # # NOTES: 'help user' in gdb will list the commands/descriptions in this file # 'context on' now enables auto-display of context screen # # MAC OS X NOTES: If you are using this on Mac OS X, you must either attach gdb to a process # or launch gdb without any options and then load the binary file you want to analyse with "exec-file" option # If you load the binary from the command line, like $gdb binary-name, this will not work as it should # For more information, read it here http://reverse.put.as/2008/11/28/apples-gdb-bug/ # # UPDATE: This bug can be fixed in gdb source. Refer to http://reverse.put.as/2009/08/10/fix-for-apples-gdb-bug-or-why-apple-forks-are-bad/ # and http://reverse.put.as/2009/08/26/gdb-patches/ (if you want the fixed binary for i386) # # An updated version of the patch and binary is available at http://reverse.put.as/2011/02/21/update-to-gdb-patches-fix-a-new-bug/ # # iOS NOTES: iOS gdb from Cydia (and Apple's) suffer from the same OS X bug. # If you are using this on Mac OS X or iOS, you must either attach gdb to a process # or launch gdb without any options and then load the binary file you want to analyse with "exec-file" option # If you load the binary from the command line, like $gdb binary-name, this will not work as it should # For more information, read it here http://reverse.put.as/2008/11/28/apples-gdb-bug/ # # CHANGELOG: (older changes at the end of the file) # # Version 8.0.4 (08/05/2013) # - Detect automatically 32 or 64 bits archs using sizeof(void*). # Thanks to Tyilo for the simple but very effective idea! # - Typo in hexdump command also fixed by vuquangtrong. # - Add shortcuts to attach to VMware kernel debugging gdb stub (kernel32 and kernel64) # # Version 8.0.3 (21/03/2013) # - Add option to colorize or not output (thanks to argp and skier for the request and ideas!) # - Convert the escape codes into functions so colors can be easily customized # - Other enhancements available at git commit logs # Thanks to Plouj, argp, xristos for their ideas and fixes! # # Version 8.0.2 (31/07/2012) # - Merge pull request from mheistermann to support local modifications in a .gdbinit.local file # - Add a missing opcode to the stepo command # # Version 8.0.1 (23/04/2012) # - Small bug fix to the attsyntax and intelsyntax commands (changing X86 flavor variable was missing) # # Version 8.0 (13/04/2012) # - Merged x86/x64 and ARM versions # - Added commands intelsyntax and attsyntax to switch between x86 disassembly flavors # - Added new configuration variables ARM, ARMOPCODES, and X86FLAVOR # - Code cleanups and fixes to the indentation # - Bug fixes to some ARM related code # - Added the dumpmacho command to memory dump the mach-o header to a file # # TODO: # # Some custom stuff: set history filename ~/.gdb_history set history save # __________________gdb options_________________ # set to 1 to have ARM target debugging as default, use the "arm" command to switch inside gdb set $ARM = 0 # set to 0 if you have problems with the colorized prompt - reported by Plouj with Ubuntu gdb 7.2 set $COLOUREDPROMPT = 0 # Colour the first line of the disassembly - default is green, if you want to change it search for # SETCOLOUR1STLINE and modify it :-) set $SETCOLOUR1STLINE = 1 # set to 0 to remove display of objectivec messages (default is 1) set $SHOWOBJECTIVEC = 1 # set to 0 to remove display of cpu registers (default is 1) set $SHOWCPUREGISTERS = 1 # set to 1 to enable display of stack (default is 0) set $SHOWSTACK = 0 # set to 1 to enable display of data window (default is 0) set $SHOWDATAWIN = 0 # set to 0 to disable coloured display of changed registers set $SHOWREGCHANGES = 1 # set to 1 so skip command to execute the instruction at the new location # by default it EIP/RIP will be modified and update the new context but not execute the instruction set $SKIPEXECUTE = 0 # if $SKIPEXECUTE is 1 configure the type of execution # 1 = use stepo (do not get into calls), 0 = use stepi (step into calls) set $SKIPSTEP = 1 # show the ARM opcodes - change to 0 if you don't want such thing (in x/i command) set $ARMOPCODES = 1 # x86 disassembly flavor: 0 for Intel, 1 for AT&T set $X86FLAVOR = 0 # use colorized output or not set $USECOLOR = 1 set confirm off set verbose off set output-radix 0x10 set input-radix 0x10 # These make gdb never pause in its output set height 0 set width 0 set $SHOW_CONTEXT = 1 set $SHOW_NEST_INSN = 0 set $CONTEXTSIZE_STACK = 6 set $CONTEXTSIZE_DATA = 8 set $CONTEXTSIZE_CODE = 8 # __________________end gdb options_________________ # # __________________color functions_________________ # # color codes set $BLACK = 0 set $RED = 1 set $GREEN = 2 set $YELLOW = 3 set $BLUE = 4 set $MAGENTA = 5 set $CYAN = 6 set $WHITE = 7 # CHANGME: If you want to modify the "theme" change the colors here # or just create a ~/.gdbinit.local and set these variables there set $COLOR_REGNAME = $GREEN set $COLOR_REGVAL = $BLACK set $COLOR_REGVAL_MODIFIED = $RED set $COLOR_SEPARATOR = $BLUE set $COLOR_CPUFLAGS = $RED # this is ugly but there's no else if available :-( define color if $USECOLOR == 0 echo \033[0m else # BLACK if $arg0 == 0 echo \033[30m else # RED if $arg0 == 1 echo \033[31m else # GREEN if $arg0 == 2 echo \033[32m else # YELLOW if $arg0 == 3 echo \033[33m else # BLUE if $arg0 == 4 echo \033[34m else # MAGENTA if $arg0 == 5 echo \033[35m else # CYAN if $arg0 == 6 echo \033[36m else # WHITE if $arg0 == 7 echo \033[37m end end end end end end end end end end define color_reset echo \033[0m end define color_bold echo \033[1m end define color_underline echo \033[4m end # can't use the color functions because we are using the set command if $COLOUREDPROMPT == 1 set prompt \033[31mgdb$ \033[0m end # this way anyone can have their custom prompt - argp's idea :-) # can also be used to redefine anything else in particular the colors aka theming # just remap the color variables defined above source ~/.gdbinit.local # Initialize these variables else comparisons will fail for colouring # we must initialize all of them at once, 32 and 64 bits, and ARM. set $oldrax = 0 set $oldrbx = 0 set $oldrcx = 0 set $oldrdx = 0 set $oldrsi = 0 set $oldrdi = 0 set $oldrbp = 0 set $oldrsp = 0 set $oldr8 = 0 set $oldr9 = 0 set $oldr10 = 0 set $oldr11 = 0 set $oldr12 = 0 set $oldr13 = 0 set $oldr14 = 0 set $oldr15 = 0 set $oldeax = 0 set $oldebx = 0 set $oldecx = 0 set $oldedx = 0 set $oldesi = 0 set $oldedi = 0 set $oldebp = 0 set $oldesp = 0 set $oldr0 = 0 set $oldr1 = 0 set $oldr2 = 0 set $oldr3 = 0 set $oldr4 = 0 set $oldr5 = 0 set $oldr6 = 0 set $oldr7 = 0 set $oldsp = 0 set $oldlr = 0 # used by ptraceme/rptraceme set $ptrace_bpnum = 0 # ______________window size control___________ define contextsize-stack if $argc != 1 help contextsize-stack else set $CONTEXTSIZE_STACK = $arg0 end end document contextsize-stack Set stack dump window size to NUM lines. Usage: contextsize-stack NUM end define contextsize-data if $argc != 1 help contextsize-data else set $CONTEXTSIZE_DATA = $arg0 end end document contextsize-data Set data dump window size to NUM lines. Usage: contextsize-data NUM end define contextsize-code if $argc != 1 help contextsize-code else set $CONTEXTSIZE_CODE = $arg0 end end document contextsize-code Set code window size to NUM lines. Usage: contextsize-code NUM end # _____________breakpoint aliases_____________ define bpl info breakpoints end document bpl List all breakpoints. end define bp if $argc != 1 help bp else break $arg0 end end document bp Set breakpoint. Usage: bp LOCATION LOCATION may be a line number, function name, or "*" and an address. To break on a symbol you must enclose symbol name inside "". Example: bp "[NSControl stringValue]" Or else you can use directly the break command (break [NSControl stringValue]) end define bpc if $argc != 1 help bpc else clear $arg0 end end document bpc Clear breakpoint. Usage: bpc LOCATION LOCATION may be a line number, function name, or "*" and an address. end define bpe if $argc != 1 help bpe else enable $arg0 end end document bpe Enable breakpoint with number NUM. Usage: bpe NUM end define bpd if $argc != 1 help bpd else disable $arg0 end end document bpd Disable breakpoint with number NUM. Usage: bpd NUM end define bpt if $argc != 1 help bpt else tbreak $arg0 end end document bpt Set a temporary breakpoint. This breakpoint will be automatically deleted when hit!. Usage: bpt LOCATION LOCATION may be a line number, function name, or "*" and an address. end define bpm if $argc != 1 help bpm else awatch $arg0 end end document bpm Set a read/write breakpoint on EXPRESSION, e.g. *address. Usage: bpm EXPRESSION end define bhb if $argc != 1 help bhb else hb $arg0 end end document bhb Set hardware assisted breakpoint. Usage: bhb LOCATION LOCATION may be a line number, function name, or "*" and an address. end define bht if $argc != 1 help bht else thbreak $arg0 end end document bht Set a temporary hardware breakpoint. This breakpoint will be automatically deleted when hit! Usage: bht LOCATION LOCATION may be a line number, function name, or "*" and an address. end # ______________process information____________ define argv show args end document argv Print program arguments. end define stack if $argc == 0 info stack end if $argc == 1 info stack $arg0 end if $argc > 1 help stack end end document stack Print backtrace of the call stack, or innermost COUNT frames. Usage: stack end define frame info frame info args info locals end document frame Print stack frame. end define flagsarm # conditional flags are # negative/less than (N), bit 31 of CPSR # zero (Z), bit 30 # Carry/Borrow/Extend (C), bit 29 # Overflow (V), bit 28 # negative/less than (N), bit 31 of CPSR if ($cpsr->n & 1) printf "N " set $_n_flag = 1 else printf "n " set $_n_flag = 0 end # zero (Z), bit 30 if ($cpsr->z & 1) printf "Z " set $_z_flag = 1 else printf "z " set $_z_flag = 0 end # Carry/Borrow/Extend (C), bit 29 if ($cpsr->c & 1) printf "C " set $_c_flag = 1 else printf "c " set $_c_flag = 0 end # Overflow (V), bit 28 if ($cpsr->v & 1) printf "V " set $_v_flag = 1 else printf "v " set $_v_flag = 0 end # Sticky overflow (Q), bit 27 if ($cpsr->q & 1) printf "Q " set $_q_flag = 1 else printf "q " set $_q_flag = 0 end # Java state bit (J), bit 24 # When T=1: # J = 0 The processor is in Thumb state. # J = 1 The processor is in ThumbEE state. if ($cpsr->j & 1) printf "J " set $_j_flag = 1 else printf "j " set $_j_flag = 0 end # Data endianness bit (E), bit 9 if ($cpsr->e & 1) printf "E " set $_e_flag = 1 else printf "e " set $_e_flag = 0 end # Imprecise abort disable bit (A), bit 8 # The A bit is set to 1 automatically. It is used to disable imprecise data aborts. # It might not be writable in the Nonsecure state if the AW bit in the SCR register is reset. if ($cpsr->a & 1) printf "A " set $_a_flag = 1 else printf "a " set $_a_flag = 0 end # IRQ disable bit (I), bit 7 # When the I bit is set to 1, IRQ interrupts are disabled. if ($cpsr->i & 1) printf "I " set $_i_flag = 1 else printf "i " set $_i_flag = 0 end # FIQ disable bit (F), bit 6 # When the F bit is set to 1, FIQ interrupts are disabled. # FIQ can be nonmaskable in the Nonsecure state if the FW bit in SCR register is reset. if ($cpsr->f & 1) printf "F " set $_f_flag = 1 else printf "f " set $_f_flag = 0 end # Thumb state bit (F), bit 5 # if 1 then the processor is executing in Thumb state or ThumbEE state depending on the J bit if ($cpsr->t & 1) printf "T " set $_t_flag = 1 else printf "t " set $_t_flag = 0 end # TODO: GE bit ? end document flagsarm Auxiliary function to set ARM cpu flags. end define flagsx86 # OF (overflow) flag if (($eflags >> 0xB) & 1) printf "O " set $_of_flag = 1 else printf "o " set $_of_flag = 0 end # DF (direction) flag if (($eflags >> 0xA) & 1) printf "D " else printf "d " end # IF (interrupt enable) flag if (($eflags >> 9) & 1) printf "I " else printf "i " end # TF (trap) flag if (($eflags >> 8) & 1) printf "T " else printf "t " end # SF (sign) flag if (($eflags >> 7) & 1) printf "S " set $_sf_flag = 1 else printf "s " set $_sf_flag = 0 end # ZF (zero) flag if (($eflags >> 6) & 1) printf "Z " set $_zf_flag = 1 else printf "z " set $_zf_flag = 0 end # AF (adjust) flag if (($eflags >> 4) & 1) printf "A " else printf "a " end # PF (parity) flag if (($eflags >> 2) & 1) printf "P " set $_pf_flag = 1 else printf "p " set $_pf_flag = 0 end # CF (carry) flag if ($eflags & 1) printf "C " set $_cf_flag = 1 else printf "c " set $_cf_flag = 0 end printf "\n" end document flagsx86 Auxiliary function to set X86/X64 cpu flags. end define flags # call the auxiliary functions based on target cpu if $ARM == 1 flagsarm else flagsx86 end end document flags Print flags register. end define eflags if $ARM == 1 printf " N <%d> Z <%d> C <%d> V <%d>",\ ($cpsr->n & 1), ($cpsr->z & 1), \ ($cpsr->c & 1), ($cpsr->v & 1) printf " Q <%d> J <%d> GE <%d> E <%d> A <%d>",\ ($cpsr->q & 1), ($cpsr->j & 1),\ ($cpsr->ge), ($cpsr->e & 1), ($cpsr->a & 1) printf " I <%d> F <%d> T <%d> \n",\ ($cpsr->i & 1), ($cpsr->f & 1), \ ($cpsr->t & 1) else printf " OF <%d> DF <%d> IF <%d> TF <%d>",\ (($eflags >> 0xB) & 1), (($eflags >> 0xA) & 1), \ (($eflags >> 9) & 1), (($eflags >> 8) & 1) printf " SF <%d> ZF <%d> AF <%d> PF <%d> CF <%d>\n",\ (($eflags >> 7) & 1), (($eflags >> 6) & 1),\ (($eflags >> 4) & 1), (($eflags >> 2) & 1), ($eflags & 1) printf " ID <%d> VIP <%d> VIF <%d> AC <%d>",\ (($eflags >> 0x15) & 1), (($eflags >> 0x14) & 1), \ (($eflags >> 0x13) & 1), (($eflags >> 0x12) & 1) printf " VM <%d> RF <%d> NT <%d> IOPL <%d>\n",\ (($eflags >> 0x11) & 1), (($eflags >> 0x10) & 1),\ (($eflags >> 0xE) & 1), (($eflags >> 0xC) & 3) end end document eflags Print eflags register. end define cpsr eflags end document cpsr Print cpsr register. end define regarm printf " " # R0 color $COLOR_REGNAME printf "R0:" if ($r0 != $oldr0 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $r0 # R1 color $COLOR_REGNAME printf "R1:" if ($r1 != $oldr1 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $r1 # R2 color $COLOR_REGNAME printf "R2:" if ($r2 != $oldr2 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $r2 # R3 color $COLOR_REGNAME printf "R3:" if ($r3 != $oldr3 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X\n", $r3 printf " " # R4 color $COLOR_REGNAME printf "R4:" if ($r4 != $oldr4 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $r4 # R5 color $COLOR_REGNAME printf "R5:" if ($r5 != $oldr5 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $r5 # R6 color $COLOR_REGNAME printf "R6:" if ($r6 != $oldr6 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $r6 # R7 color $COLOR_REGNAME printf "R7:" if ($r7 != $oldr7 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X\n", $r7 printf " " # R8 color $COLOR_REGNAME printf "R8:" if ($r8 != $oldr8 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $r8 # R9 color $COLOR_REGNAME printf "R9:" if ($r9 != $oldr9 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $r9 # R10 color $COLOR_REGNAME printf "R10:" if ($r10 != $oldr10 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $r10 # R11 color $COLOR_REGNAME printf "R11:" if ($r11 != $oldr11 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $r11 dumpjump printf "\n" # R12 color $COLOR_REGNAME printf " R12:" if ($r12 != $oldr12 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X", $r12 printf " " # SP color $COLOR_REGNAME printf "SP:" if ($sp != $oldsp && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $sp # LR color $COLOR_REGNAME printf "LR:" if ($lr != $oldlr && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $lr # PC color $COLOR_REGNAME printf "PC:" color $COLOR_REGVAL_MODIFIED printf " 0x%08X ", $pc color_bold color_underline color $COLOR_CPUFLAGS flags color_reset printf "\n" end document regarm Auxiliary function to display ARM registers. end define regx64 # 64bits stuff printf " " # RAX color $COLOR_REGNAME printf "RAX:" if ($rax != $oldrax && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $rax # RBX color $COLOR_REGNAME printf "RBX:" if ($rbx != $oldrbx && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $rbx # RBP color $COLOR_REGNAME printf "RBP:" if ($rbp != $oldrbp && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $rbp # RSP color $COLOR_REGNAME printf "RSP:" if ($rsp != $oldrsp && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $rsp color_bold color_underline color $COLOR_CPUFLAGS flags color_reset printf " " # RDI color $COLOR_REGNAME printf "RDI:" if ($rdi != $oldrdi && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $rdi # RSI color $COLOR_REGNAME printf "RSI:" if ($rsi != $oldrsi && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $rsi # RDX color $COLOR_REGNAME printf "RDX:" if ($rdx != $oldrdx && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $rdx # RCX color $COLOR_REGNAME printf "RCX:" if ($rcx != $oldrcx && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $rcx # RIP color $COLOR_REGNAME printf "RIP:" color $COLOR_REGVAL_MODIFIED printf " 0x%016lX\n ", $rip # R8 color $COLOR_REGNAME printf "R8 :" if ($r8 != $oldr8 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $r8 # R9 color $COLOR_REGNAME printf "R9 :" if ($r9 != $oldr9 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $r9 # R10 color $COLOR_REGNAME printf "R10:" if ($r10 != $oldr10 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $r10 # R11 color $COLOR_REGNAME printf "R11:" if ($r11 != $oldr11 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $r11 # R12 color $COLOR_REGNAME printf "R12:" if ($r12 != $oldr12 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX\n ", $r12 # R13 color $COLOR_REGNAME printf "R13:" if ($r13 != $oldr13 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $r13 # R14 color $COLOR_REGNAME printf "R14:" if ($r14 != $oldr14 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX ", $r14 # R15 color $COLOR_REGNAME printf "R15:" if ($r15 != $oldr15 && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%016lX\n ", $r15 color $COLOR_REGNAME printf "CS:" color $COLOR_REGVAL printf " %04X ", $cs color $COLOR_REGNAME printf "DS:" color $COLOR_REGVAL printf " %04X ", $ds color $COLOR_REGNAME printf "ES:" color $COLOR_REGVAL printf " %04X ", $es color $COLOR_REGNAME printf "FS:" color $COLOR_REGVAL printf " %04X ", $fs color $COLOR_REGNAME printf "GS:" color $COLOR_REGVAL printf " %04X ", $gs color $COLOR_REGNAME printf "SS:" color $COLOR_REGVAL printf " %04X", $ss color_reset end document regx64 Auxiliary function to display X86_64 registers. end define regx86 printf " " # EAX color $COLOR_REGNAME printf "EAX:" if ($eax != $oldeax && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $eax # EBX color $COLOR_REGNAME printf "EBX:" if ($ebx != $oldebx && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $ebx # ECX color $COLOR_REGNAME printf "ECX:" if ($ecx != $oldecx && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $ecx # EDX color $COLOR_REGNAME printf "EDX:" if ($edx != $oldedx && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $edx color_bold color_underline color $COLOR_CPUFLAGS flags color_reset printf " " # ESI color $COLOR_REGNAME printf "ESI:" if ($esi != $oldesi && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $esi # EDI color $COLOR_REGNAME printf "EDI:" if ($edi != $oldedi && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $edi # EBP color $COLOR_REGNAME printf "EBP:" if ($ebp != $oldebp && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $ebp # ESP color $COLOR_REGNAME printf "ESP:" if ($esp != $oldesp && $SHOWREGCHANGES == 1) color $COLOR_REGVAL_MODIFIED else color $COLOR_REGVAL end printf " 0x%08X ", $esp # EIP color $COLOR_REGNAME printf "EIP:" color $COLOR_REGVAL_MODIFIED printf " 0x%08X\n ", $eip color $COLOR_REGNAME printf "CS:" color $COLOR_REGVAL printf " %04X ", $cs color $COLOR_REGNAME printf "DS:" color $COLOR_REGVAL printf " %04X ", $ds color $COLOR_REGNAME printf "ES:" color $COLOR_REGVAL printf " %04X ", $es color $COLOR_REGNAME printf "FS:" color $COLOR_REGVAL printf " %04X ", $fs color $COLOR_REGNAME printf "GS:" color $COLOR_REGVAL printf " %04X ", $gs color $COLOR_REGNAME printf "SS:" color $COLOR_REGVAL printf " %04X", $ss color_reset end document regx86 Auxiliary function to display X86 registers. end define reg if $ARM == 1 regarm if ($SHOWREGCHANGES == 1) set $oldr0 = $r0 set $oldr1 = $r1 set $oldr2 = $r2 set $oldr3 = $r3 set $oldr4 = $r4 set $oldr5 = $r5 set $oldr6 = $r6 set $oldr7 = $r7 set $oldr8 = $r8 set $oldr9 = $r9 set $oldr10 = $r10 set $oldr11 = $r11 set $oldr12 = $r12 set $oldsp = $sp set $oldlr = $lr end else if (sizeof(void *) == 8) regx64 else regx86 end # call smallregisters smallregisters # display conditional jump routine if (sizeof(void *) == 8) printf "\t\t\t\t" end dumpjump printf "\n" if ($SHOWREGCHANGES == 1) if (sizeof(void *) == 8) set $oldrax = $rax set $oldrbx = $rbx set $oldrcx = $rcx set $oldrdx = $rdx set $oldrsi = $rsi set $oldrdi = $rdi set $oldrbp = $rbp set $oldrsp = $rsp set $oldr8 = $r8 set $oldr9 = $r9 set $oldr10 = $r10 set $oldr11 = $r11 set $oldr12 = $r12 set $oldr13 = $r13 set $oldr14 = $r14 set $oldr15 = $r15 else set $oldeax = $eax set $oldebx = $ebx set $oldecx = $ecx set $oldedx = $edx set $oldesi = $esi set $oldedi = $edi set $oldebp = $ebp set $oldesp = $esp end end end end document reg Print CPU registers. end define smallregisters if (sizeof(void *) == 8) #64bits stuff # from rax set $eax = $rax & 0xffffffff set $ax = $rax & 0xffff set $al = $ax & 0xff set $ah = $ax >> 8 # from rbx set $ebx = $rbx & 0xffffffff set $bx = $rbx & 0xffff set $bl = $bx & 0xff set $bh = $bx >> 8 # from rcx set $ecx = $rcx & 0xffffffff set $cx = $rcx & 0xffff set $cl = $cx & 0xff set $ch = $cx >> 8 # from rdx set $edx = $rdx & 0xffffffff set $dx = $rdx & 0xffff set $dl = $dx & 0xff set $dh = $dx >> 8 # from rsi set $esi = $rsi & 0xffffffff set $si = $rsi & 0xffff # from rdi set $edi = $rdi & 0xffffffff set $di = $rdi & 0xffff #32 bits stuff else # from eax set $ax = $eax & 0xffff set $al = $ax & 0xff set $ah = $ax >> 8 # from ebx set $bx = $ebx & 0xffff set $bl = $bx & 0xff set $bh = $bx >> 8 # from ecx set $cx = $ecx & 0xffff set $cl = $cx & 0xff set $ch = $cx >> 8 # from edx set $dx = $edx & 0xffff set $dl = $dx & 0xff set $dh = $dx >> 8 # from esi set $si = $esi & 0xffff # from edi set $di = $edi & 0xffff end end document smallregisters Create the 16 and 8 bit cpu registers (gdb doesn't have them by default). And 32bits if we are dealing with 64bits binaries. end define func if $argc == 0 info functions end if $argc == 1 info functions $arg0 end if $argc > 1 help func end end document func Print all function names in target, or those matching REGEXP. Usage: func end define var if $argc == 0 info variables end if $argc == 1 info variables $arg0 end if $argc > 1 help var end end document var Print all global and static variable names (symbols), or those matching REGEXP. Usage: var end define lib info sharedlibrary end document lib Print shared libraries linked to target. end define sig if $argc == 0 info signals end if $argc == 1 info signals $arg0 end if $argc > 1 help sig end end document sig Print what debugger does when program gets various signals. Specify a SIGNAL as argument to print info on that signal only. Usage: sig end define threads info threads end document threads Print threads in target. end define dis if $argc == 0 disassemble end if $argc == 1 disassemble $arg0 end if $argc == 2 disassemble $arg0 $arg1 end if $argc > 2 help dis end end document dis Disassemble a specified section of memory. Default is to disassemble the function surrounding the PC (program counter) of selected frame. With one argument, ADDR1, the function surrounding this address is dumped. Two arguments are taken as a range of memory to dump. Usage: dis end # __________hex/ascii dump an address_________ define ascii_char if $argc != 1 help ascii_char else # thanks elaine :) set $_c = *(unsigned char *)($arg0) if ($_c < 0x20 || $_c > 0x7E) printf "." else printf "%c", $_c end end end document ascii_char Print ASCII value of byte at address ADDR. Print "." if the value is unprintable. Usage: ascii_char ADDR end define hex_quad if $argc != 1 help hex_quad else printf "%02X %02X %02X %02X %02X %02X %02X %02X", \ *(unsigned char*)($arg0), *(unsigned char*)($arg0 + 1), \ *(unsigned char*)($arg0 + 2), *(unsigned char*)($arg0 + 3), \ *(unsigned char*)($arg0 + 4), *(unsigned char*)($arg0 + 5), \ *(unsigned char*)($arg0 + 6), *(unsigned char*)($arg0 + 7) end end document hex_quad Print eight hexadecimal bytes starting at address ADDR. Usage: hex_quad ADDR end define hexdump if $argc == 1 hexdump_aux $arg0 else if $argc == 2 set $_count = 0 while ($_count < $arg1) set $_i = ($_count * 0x10) hexdump_aux $arg0+$_i set $_count++ end else help hexdump end end end document hexdump Display a 16-byte hex/ASCII dump of memory starting at address ADDR. Optional parameter is the number of lines to display if you want more than one. Usage: hexdump ADDR [nr lines] end define hexdump_aux if $argc != 1 help hexdump_aux else color_bold if (sizeof(void *) == 8) printf "0x%016lX : ", $arg0 else printf "0x%08X : ", $arg0 end color_reset hex_quad $arg0 color_bold printf " - " color_reset hex_quad $arg0+8 printf " " color_bold ascii_char $arg0+0x0 ascii_char $arg0+0x1 ascii_char $arg0+0x2 ascii_char $arg0+0x3 ascii_char $arg0+0x4 ascii_char $arg0+0x5 ascii_char $arg0+0x6 ascii_char $arg0+0x7 ascii_char $arg0+0x8 ascii_char $arg0+0x9 ascii_char $arg0+0xA ascii_char $arg0+0xB ascii_char $arg0+0xC ascii_char $arg0+0xD ascii_char $arg0+0xE ascii_char $arg0+0xF color_reset printf "\n" end end document hexdump_aux Display a 16-byte hex/ASCII dump of memory at address ADDR. Usage: hexdump_aux ADDR end # _______________data window__________________ define ddump if $argc != 1 help ddump else color $COLOR_SEPARATOR if (sizeof(void *) == 8) printf "[0x%04X:0x%016lX]", $ds, $data_addr else printf "[0x%04X:0x%08X]", $ds, $data_addr end color $COLOR_SEPARATOR printf "------------------------" printf "-------------------------------" if (sizeof(void *) == 8) printf "-------------------------------------" end color_bold color $COLOR_SEPARATOR printf "[data]\n" color_reset set $_count = 0 while ($_count < $arg0) set $_i = ($_count * 0x10) hexdump $data_addr+$_i set $_count++ end end end document ddump Display NUM lines of hexdump for address in $data_addr global variable. Usage: ddump NUM end define dd if $argc != 1 help dd else set $data_addr = $arg0 ddump 0x10 end end document dd Display 16 lines of a hex dump of address starting at ADDR. Usage: dd ADDR end define datawin if $ARM == 1 if ((($r0 >> 0x18) == 0x40) || (($r0 >> 0x18) == 0x08) || (($r0 >> 0x18) == 0xBF)) set $data_addr = $r0 else if ((($r1 >> 0x18) == 0x40) || (($r1 >> 0x18) == 0x08) || (($r1 >> 0x18) == 0xBF)) set $data_addr = $r1 else if ((($r2 >> 0x18) == 0x40) || (($r2 >> 0x18) == 0x08) || (($r2 >> 0x18) == 0xBF)) set $data_addr = $r2 else set $data_addr = $sp end end end ################################# X86 else if (sizeof(void *) == 8) if ((($rsi >> 0x18) == 0x40) || (($rsi >> 0x18) == 0x08) || (($rsi >> 0x18) == 0xBF)) set $data_addr = $rsi else if ((($rdi >> 0x18) == 0x40) || (($rdi >> 0x18) == 0x08) || (($rdi >> 0x18) == 0xBF)) set $data_addr = $rdi else if ((($rax >> 0x18) == 0x40) || (($rax >> 0x18) == 0x08) || (($rax >> 0x18) == 0xBF)) set $data_addr = $rax else set $data_addr = $rsp end end end else if ((($esi >> 0x18) == 0x40) || (($esi >> 0x18) == 0x08) || (($esi >> 0x18) == 0xBF)) set $data_addr = $esi else if ((($edi >> 0x18) == 0x40) || (($edi >> 0x18) == 0x08) || (($edi >> 0x18) == 0xBF)) set $data_addr = $edi else if ((($eax >> 0x18) == 0x40) || (($eax >> 0x18) == 0x08) || (($eax >> 0x18) == 0xBF)) set $data_addr = $eax else set $data_addr = $esp end end end end end ddump $CONTEXTSIZE_DATA end document datawin Display valid address from one register in data window. Registers to choose are: esi, edi, eax, or esp. end ################################ ##### ALERT ALERT ALERT ######## ################################ # Huge mess going here :) HAHA # ################################ define dumpjump if $ARM == 1 ## Most ARM and Thumb instructions are conditional! # each instruction is 32 bits long # 4 bits are for condition codes (16 in total) (bits 31:28 in ARM contain the condition or 1111 if instruction is unconditional) # 2x4 bits for destination and first operand registers # one for the set-status flag # an assorted number for other stuff # 12 bits for any immediate value # $_t_flag == 0 => ARM mode # $_t_flag == 1 => Thumb or ThumbEE if ($cpsr->t & 1) set $_t_flag = 1 else set $_t_flag = 0 end if $_t_flag == 0 set $_lastbyte = *(unsigned char *)($pc+3) #set $_bit31 = ($_lastbyte >> 7) & 1 #set $_bit30 = ($_lastbyte >> 6) & 1 #set $_bit29 = ($_lastbyte >> 5) & 1 #set $_bit28 = ($_lastbyte >> 4) & 1 set $_conditional = $_lastbyte >> 4 dumpjumphelper else # if bits 15-12 (opcode in Thumb instructions) are equal to 1 1 0 1 (0xD) then we have a conditional branch # bits 11-8 for the conditional execution code (check ARMv7 manual A8.3) if ( (*(unsigned char *)($pc+1) >> 4) == 0xD ) set $_conditional = *(unsigned char *)($pc+1) ^ 0xD0 dumpjumphelper end end ##################### X86 else ## grab the first two bytes from the instruction so we can determine the jump instruction set $_byte1 = *(unsigned char *)$pc set $_byte2 = *(unsigned char *)($pc+1) ## and now check what kind of jump we have (in case it's a jump instruction) ## I changed the flags routine to save the flag into a variable, so we don't need to repeat the process :) (search for "define flags") ## opcode 0x77: JA, JNBE (jump if CF=0 and ZF=0) ## opcode 0x0F87: JNBE, JA if ( ($_byte1 == 0x77) || ($_byte1 == 0x0F && $_byte2 == 0x87) ) # cf=0 and zf=0 if ($_cf_flag == 0 && $_zf_flag == 0) color $RED printf " Jump is taken (c=0 and z=0)" else # cf != 0 or zf != 0 color $RED printf " Jump is NOT taken (c!=0 or z!=0)" end end ## opcode 0x73: JAE, JNB, JNC (jump if CF=0) ## opcode 0x0F83: JNC, JNB, JAE (jump if CF=0) if ( ($_byte1 == 0x73) || ($_byte1 == 0x0F && $_byte2 == 0x83) ) # cf=0 if ($_cf_flag == 0) color $RED printf " Jump is taken (c=0)" else # cf != 0 color $RED printf " Jump is NOT taken (c!=0)" end end ## opcode 0x72: JB, JC, JNAE (jump if CF=1) ## opcode 0x0F82: JNAE, JB, JC if ( ($_byte1 == 0x72) || ($_byte1 == 0x0F && $_byte2 == 0x82) ) # cf=1 if ($_cf_flag == 1) color $RED printf " Jump is taken (c=1)" else # cf != 1 color $RED printf " Jump is NOT taken (c!=1)" end end ## opcode 0x76: JBE, JNA (jump if CF=1 or ZF=1) ## opcode 0x0F86: JBE, JNA if ( ($_byte1 == 0x76) || ($_byte1 == 0x0F && $_byte2 == 0x86) ) # cf=1 or zf=1 if (($_cf_flag == 1) || ($_zf_flag == 1)) color $RED printf " Jump is taken (c=1 or z=1)" else # cf != 1 or zf != 1 color $RED printf " Jump is NOT taken (c!=1 or z!=1)" end end ## opcode 0xE3: JCXZ, JECXZ, JRCXZ (jump if CX=0 or ECX=0 or RCX=0) if ($_byte1 == 0xE3) # cx=0 or ecx=0 if (($ecx == 0) || ($cx == 0)) color $RED printf " Jump is taken (cx=0 or ecx=0)" else color $RED printf " Jump is NOT taken (cx!=0 or ecx!=0)" end end ## opcode 0x74: JE, JZ (jump if ZF=1) ## opcode 0x0F84: JZ, JE, JZ (jump if ZF=1) if ( ($_byte1 == 0x74) || ($_byte1 == 0x0F && $_byte2 == 0x84) ) # ZF = 1 if ($_zf_flag == 1) color $RED printf " Jump is taken (z=1)" else # ZF = 0 color $RED printf " Jump is NOT taken (z!=1)" end end ## opcode 0x7F: JG, JNLE (jump if ZF=0 and SF=OF) ## opcode 0x0F8F: JNLE, JG (jump if ZF=0 and SF=OF) if ( ($_byte1 == 0x7F) || ($_byte1 == 0x0F && $_byte2 == 0x8F) ) # zf = 0 and sf = of if (($_zf_flag == 0) && ($_sf_flag == $_of_flag)) color $RED printf " Jump is taken (z=0 and s=o)" else color $RED printf " Jump is NOT taken (z!=0 or s!=o)" end end ## opcode 0x7D: JGE, JNL (jump if SF=OF) ## opcode 0x0F8D: JNL, JGE (jump if SF=OF) if ( ($_byte1 == 0x7D) || ($_byte1 == 0x0F && $_byte2 == 0x8D) ) # sf = of if ($_sf_flag == $_of_flag) color $RED printf " Jump is taken (s=o)" else color $RED printf " Jump is NOT taken (s!=o)" end end ## opcode: 0x7C: JL, JNGE (jump if SF != OF) ## opcode: 0x0F8C: JNGE, JL (jump if SF != OF) if ( ($_byte1 == 0x7C) || ($_byte1 == 0x0F && $_byte2 == 0x8C) ) # sf != of if ($_sf_flag != $_of_flag) color $RED printf " Jump is taken (s!=o)" else color $RED printf " Jump is NOT taken (s=o)" end end ## opcode 0x7E: JLE, JNG (jump if ZF = 1 or SF != OF) ## opcode 0x0F8E: JNG, JLE (jump if ZF = 1 or SF != OF) if ( ($_byte1 == 0x7E) || ($_byte1 == 0x0F && $_byte2 == 0x8E) ) # zf = 1 or sf != of if (($_zf_flag == 1) || ($_sf_flag != $_of_flag)) color $RED printf " Jump is taken (zf=1 or sf!=of)" else color $RED printf " Jump is NOT taken (zf!=1 or sf=of)" end end ## opcode 0x75: JNE, JNZ (jump if ZF = 0) ## opcode 0x0F85: JNE, JNZ (jump if ZF = 0) if ( ($_byte1 == 0x75) || ($_byte1 == 0x0F && $_byte2 == 0x85) ) # ZF = 0 if ($_zf_flag == 0) color $RED printf " Jump is taken (z=0)" else # ZF = 1 color $RED printf " Jump is NOT taken (z!=0)" end end ## opcode 0x71: JNO (OF = 0) ## opcode 0x0F81: JNO (OF = 0) if ( ($_byte1 == 0x71) || ($_byte1 == 0x0F && $_byte2 == 0x81) ) # OF = 0 if ($_of_flag == 0) color $RED printf " Jump is taken (o=0)" else # OF != 0 color $RED printf " Jump is NOT taken (o!=0)" end end ## opcode 0x7B: JNP, JPO (jump if PF = 0) ## opcode 0x0F8B: JPO (jump if PF = 0) if ( ($_byte1 == 0x7B) || ($_byte1 == 0x0F && $_byte2 == 0x8B) ) # PF = 0 if ($_pf_flag == 0) color $RED printf " Jump is NOT taken (p=0)" else # PF != 0 color $RED printf " Jump is taken (p!=0)" end end ## opcode 0x79: JNS (jump if SF = 0) ## opcode 0x0F89: JNS (jump if SF = 0) if ( ($_byte1 == 0x79) || ($_byte1 == 0x0F && $_byte2 == 0x89) ) # SF = 0 if ($_sf_flag == 0) color $RED printf " Jump is taken (s=0)" else # SF != 0 color $RED printf " Jump is NOT taken (s!=0)" end end ## opcode 0x70: JO (jump if OF=1) ## opcode 0x0F80: JO (jump if OF=1) if ( ($_byte1 == 0x70) || ($_byte1 == 0x0F && $_byte2 == 0x80) ) # OF = 1 if ($_of_flag == 1) color $RED printf " Jump is taken (o=1)" else # OF != 1 color $RED printf " Jump is NOT taken (o!=1)" end end ## opcode 0x7A: JP, JPE (jump if PF=1) ## opcode 0x0F8A: JP, JPE (jump if PF=1) if ( ($_byte1 == 0x7A) || ($_byte1 == 0x0F && $_byte2 == 0x8A) ) # PF = 1 if ($_pf_flag == 1) color $RED printf " Jump is taken (p=1)" else # PF = 0 color $RED printf " Jump is NOT taken (p!=1)" end end ## opcode 0x78: JS (jump if SF=1) ## opcode 0x0F88: JS (jump if SF=1) if ( ($_byte1 == 0x78) || ($_byte1 == 0x0F && $_byte2 == 0x88) ) # SF = 1 if ($_sf_flag == 1) color $RED printf " Jump is taken (s=1)" else # SF != 1 color $RED printf " Jump is NOT taken (s!=1)" end end end end document dumpjump Display if conditional jump will be taken or not. end define dumpjumphelper # 0000 - EQ: Z == 1 if ($_conditional == 0x0) if ($_z_flag == 1) color $RED printf " Jump is taken (z==1)" else color $RED printf " Jump is NOT taken (z!=1)" end end # 0001 - NE: Z == 0 if ($_conditional == 0x1) if ($_z_flag == 0) color $RED printf " Jump is taken (z==0)" else color $RED printf " Jump is NOT taken (z!=0)" end end # 0010 - CS: C == 1 if ($_conditional == 0x2) if ($_c_flag == 1) color $RED printf " Jump is taken (c==1)" else color $RED printf " Jump is NOT taken (c!=1)" end end # 0011 - CC: C == 0 if ($_conditional == 0x3) if ($_c_flag == 0) color $RED printf " Jump is taken (c==0)" else color $RED printf " Jump is NOT taken (c!=0)" end end # 0100 - MI: N == 1 if ($_conditional == 0x4) if ($_n_flag == 1) color $RED printf " Jump is taken (n==1)" else color $RED printf " Jump is NOT taken (n!=1)" end end # 0101 - PL: N == 0 if ($_conditional == 0x5) if ($_n_flag == 0) color $RED printf " Jump is taken (n==0)" else color $RED printf " Jump is NOT taken (n!=0)" end end # 0110 - VS: V == 1 if ($_conditional == 0x6) if ($_v_flag == 1) color $RED printf " Jump is taken (v==1)" else color $RED printf " Jump is NOT taken (v!=1)" end end # 0111 - VC: V == 0 if ($_conditional == 0x7) if ($_v_flag == 0) color $RED printf " Jump is taken (v==0)" else color $RED printf " Jump is NOT taken (v!=0)" end end # 1000 - HI: C == 1 and Z == 0 if ($_conditional == 0x8) if ($_c_flag == 1 && $_z_flag == 0) color $RED printf " Jump is taken (c==1 and z==0)" else color $RED printf " Jump is NOT taken (c!=1 or z!=0)" end end # 1001 - LS: C == 0 or Z == 1 if ($_conditional == 0x9) if ($_c_flag == 0 || $_z_flag == 1) color $RED printf " Jump is taken (c==0 or z==1)" else color $RED printf " Jump is NOT taken (c!=0 or z!=1)" end end # 1010 - GE: N == V if ($_conditional == 0xA) if ($_n_flag == $_v_flag) color $RED printf " Jump is taken (n==v)" else color $RED printf " Jump is NOT taken (n!=v)" end end # 1011 - LT: N != V if ($_conditional == 0xB) if ($_n_flag != $_v_flag) color $RED printf " Jump is taken (n!=v)" else color $RED printf " Jump is NOT taken (n==v)" end end # 1100 - GT: Z == 0 and N == V if ($_conditional == 0xC) if ($_z_flag == 0 && $_n_flag == $_v_flag) color $RED printf " Jump is taken (z==0 and n==v)" else color $RED printf " Jump is NOT taken (z!=0 or n!=v)" end end # 1101 - LE: Z == 1 or N != V if ($_conditional == 0xD) if ($_z_flag == 1 || $_n_flag != $_v_flag) color $RED printf " Jump is taken (z==1 or n!=v)" else color $RED printf " Jump is NOT taken (z!=1 or n==v)" end end end document dumpjumphelper Helper function to decide if conditional jump will be taken or not, for ARM and Thumb. end # _______________process context______________ # initialize variable set $displayobjectivec = 0 define context color $COLOR_SEPARATOR if $SHOWCPUREGISTERS == 1 printf "----------------------------------------" printf "----------------------------------" if (sizeof(void *) == 8) printf "---------------------------------------------" end color $COLOR_SEPARATOR color_bold printf "[regs]\n" color_reset reg color $CYAN end if $SHOWSTACK == 1 color $COLOR_SEPARATOR if (sizeof(void *) == 8) printf "[0x%04X:0x%016lX]", $ss, $rsp else printf "[0x%04X:0x%08X]", $ss, $esp end color $COLOR_SEPARATOR printf "-------------------------" printf "-----------------------------" if (sizeof(void *) == 8) printf "-------------------------------------" end color $COLOR_SEPARATOR color_bold printf "[stack]\n" color_reset set $context_i = $CONTEXTSIZE_STACK while ($context_i > 0) set $context_t = $sp + 0x10 * ($context_i - 1) hexdump $context_t set $context_i-- end end # show the objective C message being passed to msgSend if $SHOWOBJECTIVEC == 1 #FIXME: X64 and ARM # What a piece of crap that's going on here :) # detect if it's the correct opcode we are searching for if $ARM == 0 set $__byte1 = *(unsigned char *)$pc set $__byte = *(int *)$pc if ($__byte == 0x4244489) set $objectivec = $eax set $displayobjectivec = 1 end if ($__byte == 0x4245489) set $objectivec = $edx set $displayobjectivec = 1 end if ($__byte == 0x4244c89) set $objectivec = $ecx set $displayobjectivec = 1 end else set $__byte1 = 0 end # and now display it or not (we have no interest in having the info displayed after the call) if $__byte1 == 0xE8 if $displayobjectivec == 1 color $COLOR_SEPARATOR printf "--------------------------------------------------------------------" if (sizeof(void *) == 8) printf "---------------------------------------------" end color $COLOR_SEPARATOR color_bold printf "[ObjectiveC]\n" color_reset color $BLACK x/s $objectivec end set $displayobjectivec = 0 end if $displayobjectivec == 1 color $COLOR_SEPARATOR printf "--------------------------------------------------------------------" if (sizeof(void *) == 8) printf "---------------------------------------------" end color $COLOR_SEPARATOR color_bold printf "[ObjectiveC]\n" color_reset color $BLACK x/s $objectivec end end color_reset # and this is the end of this little crap if $SHOWDATAWIN == 1 datawin end color $COLOR_SEPARATOR printf "--------------------------------------------------------------------------" if (sizeof(void *) == 8) printf "---------------------------------------------" end color $COLOR_SEPARATOR color_bold printf "[code]\n" color_reset set $context_i = $CONTEXTSIZE_CODE if ($context_i > 0) if ($SETCOLOUR1STLINE == 1) color $GREEN x /i $pc color_reset else x /i $pc end set $context_i-- end while ($context_i > 0) x /i set $context_i-- end color $COLOR_SEPARATOR printf "----------------------------------------" printf "----------------------------------------" if (sizeof(void *) == 8) printf "---------------------------------------------\n" else printf "\n" end color_reset end document context Print context window, i.e. regs, stack, ds:esi and disassemble cs:eip. end define context-on set $SHOW_CONTEXT = 1 printf "Displaying of context is now ON\n" end document context-on Enable display of context on every program break. end define context-off set $SHOW_CONTEXT = 0 printf "Displaying of context is now OFF\n" end document context-off Disable display of context on every program break. end # _______________process control______________ define n if $argc == 0 nexti end if $argc == 1 nexti $arg0 end if $argc > 1 help n end end document n Step one instruction, but proceed through subroutine calls. If NUM is given, then repeat it NUM times or till program stops. This is alias for nexti. Usage: n end define go if $argc == 0 stepi end if $argc == 1 stepi $arg0 end if $argc > 1 help go end end document go Step one instruction exactly. If NUM is given, then repeat it NUM times or till program stops. This is alias for stepi. Usage: go end define pret finish end document pret Execute until selected stack frame returns (step out of current call). Upon return, the value returned is printed and put in the value history. end define init set $SHOW_NEST_INSN = 0 tbreak _init r end document init Run program and break on _init(). end define start set $SHOW_NEST_INSN = 0 tbreak _start r end document start Run program and break on _start(). end define sstart set $SHOW_NEST_INSN = 0 tbreak __libc_start_main r end document sstart Run program and break on __libc_start_main(). Useful for stripped executables. end define main set $SHOW_NEST_INSN = 0 tbreak main r end document main Run program and break on main(). end # FIXME64 #### WARNING ! WARNING !! #### More more messy stuff starting !!! #### I was thinking about how to do this and then it ocurred me that it could be as simple as this ! :) define stepoframework if $ARM == 1 # bl and bx opcodes # bx Rn => ARM bits 27-20: 0 0 0 1 0 0 1 0 , bits 7-4: 0 0 0 1 ; Thumb bits: 15-7: 0 1 0 0 0 1 1 1 0 # blx Rn => ARM bits 27-20: 0 0 0 1 0 0 1 0 , bits 7-4: 0 0 1 1 ; Thumb bits: 15-7: 0 1 0 0 0 1 1 1 1 # bl # => ARM bits 27-24: 1 0 1 1 ; Thumb bits: 15-11: 1 1 1 1 0 # blx # => ARM bits 31-25: 1 1 1 1 1 0 1 ; Thumb bits: 15-11: 1 1 1 1 0 set $_nextaddress = 0 # ARM Mode if ($_t_flag == 0) set $_branchesint = *(unsigned int*)$pc set $_bit31 = ($_branchesint >> 0x1F) & 1 set $_bit30 = ($_branchesint >> 0x1E) & 1 set $_bit29 = ($_branchesint >> 0x1D) & 1 set $_bit28 = ($_branchesint >> 0x1C) & 1 set $_bit27 = ($_branchesint >> 0x1B) & 1 set $_bit26 = ($_branchesint >> 0x1A) & 1 set $_bit25 = ($_branchesint >> 0x19) & 1 set $_bit24 = ($_branchesint >> 0x18) & 1 set $_bit23 = ($_branchesint >> 0x17) & 1 set $_bit22 = ($_branchesint >> 0x16) & 1 set $_bit21 = ($_branchesint >> 0x15) & 1 set $_bit20 = ($_branchesint >> 0x14) & 1 set $_bit7 = ($_branchesint >> 0x7) & 1 set $_bit6 = ($_branchesint >> 0x6) & 1 set $_bit5 = ($_branchesint >> 0x5) & 1 set $_bit4 = ($_branchesint >> 0x4) & 1 # set $_lastbyte = *(unsigned char *)($pc+3) # set $_bits2724 = $_lastbyte & 0x1 # set $_bits3128 = $_lastbyte >> 4 # if ($_bits3128 == 0xF) # set $_bits2724 = $_lastbyte & 0xA # set $_bits2724 = $_bits2724 >> 1 # end # set $_previousbyte = *(unsigned char *)($pc+2) # set $_bits2320 = $_previousbyte >> 4 # printf "bits2724: %x bits2320: %x\n", $_bits2724, $_bits2320 if ($_bit27 == 0 && $_bit26 == 0 && $_bit25 == 0 && $_bit24 == 1 && $_bit23 == 0 && $_bit22 == 0 && $_bit21 == 1 && $_bit20 == 0 && $_bit7 == 0 && $_bit6 == 0 && $_bit5 == 0 && $_bit4 == 1) printf "Found a bx Rn\n" set $_nextaddress = $pc+0x4 end if ($_bit27 == 0 && $_bit26 == 0 && $_bit25 == 0 && $_bit24 == 1 && $_bit23 == 0 && $_bit22 == 0 && $_bit21 == 1 && $_bit20 == 0 && $_bit7 == 0 && $_bit6 == 0 && $_bit5 == 1 && $_bit4 == 1) printf "Found a blx Rn\n" set $_nextaddress = $pc+0x4 end if ($_bit27 == 1 && $_bit26 == 0 && $_bit25 == 1 && $_bit24 == 1) printf "Found a bl #\n" set $_nextaddress = $pc+0x4 end if ($_bit31 == 1 && $_bit30 == 1 && $_bit29 == 1 && $_bit28 == 1 && $_bit27 == 1 && $_bit26 == 0 && $_bit25 == 1) printf "Found a blx #\n" set $_nextaddress = $pc+0x4 end # Thumb Mode else # 32 bits instructions in Thumb are divided into two half words set $_hw1 = *(unsigned short*)($pc) set $_hw2 = *(unsigned short*)($pc+2) # bl/blx (immediate) # hw1: bits 15-11: 1 1 1 1 0 # hw2: bits 15-14: 1 1 ; BL bit 12: 1 ; BLX bit 12: 0 if ( ($_hw1 >> 0xC) == 0xF && (($_hw1 >> 0xB) & 1) == 0) if ( ((($_hw2 >> 0xF) & 1) == 1) && ((($_hw2 >> 0xE) & 1) == 1) ) set $_nextaddress = $pc+0x4 end end end # if we have found a call to bypass we set a temporary breakpoint on next instruction and continue if ($_nextaddress != 0) tbreak *$_nextaddress continue printf "[StepO] Next address will be %x\n", $_nextaddress # else we just single step else nexti end ###################################### X86 else ## we know that an opcode starting by 0xE8 has a fixed length ## for the 0xFF opcodes, we can enumerate what is possible to have # first we grab the first 3 bytes from the current program counter set $_byte1 = *(unsigned char *)$pc set $_byte2 = *(unsigned char *)($pc+1) set $_byte3 = *(unsigned char *)($pc+2) # and start the fun # if it's a 0xE8 opcode, the total instruction size will be 5 bytes # so we can simply calculate the next address and use a temporary breakpoint ! Voila :) set $_nextaddress = 0 # this one is the must useful for us !!! if ($_byte1 == 0xE8) set $_nextaddress = $pc + 0x5 else # just other cases we might be interested in... maybe this should be removed since the 0xE8 opcode is the one we will use more # this is a big fucking mess and can be improved for sure :) I don't like the way it is ehehehe if ($_byte1 == 0xFF) # call *%eax (0xFFD0) || call *%edx (0xFFD2) || call *(%ecx) (0xFFD1) || call (%eax) (0xFF10) || call *%esi (0xFFD6) || call *%ebx (0xFFD3) || call DWORD PTR [edx] (0xFF12) if ($_byte2 == 0xD0 || $_byte2 == 0xD1 || $_byte2 == 0xD2 || $_byte2 == 0xD3 || $_byte2 == 0xD6 || $_byte2 == 0x10 || $_byte2 == 0x11 || $_byte2 == 0xD7 || $_byte2 == 0x12) set $_nextaddress = $pc + 0x2 end # call *0x??(%ebp) (0xFF55??) || call *0x??(%esi) (0xFF56??) || call *0x??(%edi) (0xFF5F??) || call *0x??(%ebx) # call *0x??(%edx) (0xFF52??) || call *0x??(%ecx) (0xFF51??) || call *0x??(%edi) (0xFF57??) || call *0x??(%eax) (0xFF50??) if ($_byte2 == 0x55 || $_byte2 == 0x56 || $_byte2 == 0x5F || $_byte2 == 0x53 || $_byte2 == 0x52 || $_byte2 == 0x51 || $_byte2 == 0x57 || $_byte2 == 0x50) set $_nextaddress = $pc + 0x3 end # call *0x????????(%ebx) (0xFF93????????) || if ($_byte2 == 0x93 || $_byte2 == 0x94 || $_byte2 == 0x90 || $_byte2 == 0x92 || $_byte2 == 0x95) set $_nextaddress = $pc + 6 end # call *0x????????(%ebx,%eax,4) (0xFF94??????????) if ($_byte2 == 0x94) set $_nextaddress = $pc + 7 end end # FIXME: still missing a few? if ($_byte1 == 0x41 || $_byte1 == 0x40) if ($_byte2 == 0xFF) if ($_byte3 == 0xD0 || $_byte3 == 0xD1 || $_byte3 == 0xD2 || $_byte3 == 0xD3 || $_byte3 == 0xD4 || $_byte3 == 0xD5 || $_byte3 == 0xD6 || $_byte3 == 0xD7) set $_nextaddress = $pc + 0x3 end end end end # if we have found a call to bypass we set a temporary breakpoint on next instruction and continue if ($_nextaddress != 0) if ($arg0 == 1) thbreak *$_nextaddress else tbreak *$_nextaddress end continue # else we just single step else nexti end end end document stepoframework Auxiliary function to stepo command. end define stepo stepoframework 0 end document stepo Step over calls (interesting to bypass the ones to msgSend). 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 or n since it will single step code if it's not a call instruction (unless you want to go into the call function). end define stepoh stepoframework 1 end document stepoh Same as stepo command but uses temporary hardware breakpoints. end # FIXME: ARM define skip x/2i $pc set $instruction_size = (int)($_ - $pc) set $pc = $pc + $instruction_size if ($SKIPEXECUTE == 1) if ($SKIPSTEP == 1) stepo else stepi end else context end end document skip Skip over the instruction located at EIP/RIP. By default, the instruction will not be executed! Some configurable options are available on top of gdbinit to override this. end # _______________eflags commands______________ # conditional flags are # negative/less than (N), bit 31 of CPSR # zero (Z), bit 30 # Carry/Borrow/Extend (C), bit 29 # Overflow (V), bit 28 # negative/less than (N), bit 31 of CPSR define cfn if $ARM == 1 set $tempflag = $cpsr->n if ($tempflag & 1) set $cpsr->n = $tempflag&~0x1 else set $cpsr->n = $tempflag|0x1 end end end document cfn Change Negative/Less Than Flag. end define cfc # Carry/Borrow/Extend (C), bit 29 if $ARM == 1 set $tempflag = $cpsr->c if ($tempflag & 1) set $cpsr->c = $tempflag&~0x1 else set $cpsr->c = $tempflag|0x1 end else if ($eflags & 1) set $eflags = $eflags&~0x1 else set $eflags = $eflags|0x1 end end end document cfc Change Carry Flag. end define cfp if (($eflags >> 2) & 1) set $eflags = $eflags&~0x4 else set $eflags = $eflags|0x4 end end document cfp Change Parity Flag. end define cfa if (($eflags >> 4) & 1) set $eflags = $eflags&~0x10 else set $eflags = $eflags|0x10 end end document cfa Change Auxiliary Carry Flag. end define cfz # zero (Z), bit 30 if $ARM == 1 set $tempflag = $cpsr->z if ($tempflag & 1) set $cpsr->z = $tempflag&~0x1 else set $cpsr->z = $tempflag|0x1 end else if (($eflags >> 6) & 1) set $eflags = $eflags&~0x40 else set $eflags = $eflags|0x40 end end end document cfz Change Zero Flag. end define cfs if (($eflags >> 7) & 1) set $eflags = $eflags&~0x80 else set $eflags = $eflags|0x80 end end document cfs Change Sign Flag. end define cft if (($eflags >>8) & 1) set $eflags = $eflags&~0x100 else set $eflags = $eflags|0x100 end end document cft Change Trap Flag. end define cfi if (($eflags >> 9) & 1) set $eflags = $eflags&~0x200 else set $eflags = $eflags|0x200 end end document cfi Change Interrupt Flag. Only privileged applications (usually the OS kernel) may modify IF. This only applies to protected mode (real mode code may always modify IF). end define cfd if (($eflags >>0xA) & 1) set $eflags = $eflags&~0x400 else set $eflags = $eflags|0x400 end end document cfd Change Direction Flag. end define cfo if (($eflags >> 0xB) & 1) set $eflags = $eflags&~0x800 else set $eflags = $eflags|0x800 end end document cfo Change Overflow Flag. end # Overflow (V), bit 28 define cfv if $ARM == 1 set $tempflag = $cpsr->v if ($tempflag & 1) set $cpsr->v = $tempflag&~0x1 else set $cpsr->v = $tempflag|0x1 end end end document cfv Change Overflow Flag. end # ____________________patch___________________ # the usual nops are mov r0,r0 for arm (0xe1a00000) # and mov r8,r8 in Thumb (0x46c0) # armv7 has other nops # FIXME: make sure that the interval fits the 32bits address for arm and 16bits for thumb # status: works, fixme define nop if ($argc > 2 || $argc == 0) help nop end if $ARM == 1 if ($argc == 1) if ($cpsr->t &1) # thumb set *(short *)$arg0 = 0x46c0 else # arm set *(int *)$arg0 = 0xe1a00000 end else set $addr = $arg0 if ($cpsr->t & 1) # thumb while ($addr < $arg1) set *(short *)$addr = 0x46c0 set $addr = $addr + 2 end else # arm while ($addr < $arg1) set *(int *)$addr = 0xe1a00000 set $addr = $addr + 4 end end end else if ($argc == 1) set *(unsigned char *)$arg0 = 0x90 else set $addr = $arg0 while ($addr < $arg1) set *(unsigned char *)$addr = 0x90 set $addr = $addr + 1 end end end end document nop Usage: nop ADDR1 [ADDR2] Patch a single byte at address ADDR1, or a series of bytes between ADDR1 and ADDR2 to a NOP (0x90) instruction. ARM or Thumb code will be patched accordingly. end define null if ( $argc >2 || $argc == 0) help null end if ($argc == 1) set *(unsigned char *)$arg0 = 0 else set $addr = $arg0 while ($addr < $arg1) set *(unsigned char *)$addr = 0 set $addr = $addr +1 end end end document null Usage: null ADDR1 [ADDR2] Patch a single byte at address ADDR1 to NULL (0x00), or a series of bytes between ADDR1 and ADDR2. end # FIXME: thumb breakpoint ? define int3 if $argc != 1 help int3 else if $ARM == 1 set $ORIGINAL_INT3 = *(unsigned int *)$arg0 set $ORIGINAL_INT3ADDRESS = $arg0 set *(unsigned int*)$arg0 = 0xe7ffdefe else # save original bytes and address set $ORIGINAL_INT3 = *(unsigned char *)$arg0 set $ORIGINAL_INT3ADDRESS = $arg0 # patch set *(unsigned char *)$arg0 = 0xCC end end end document int3 Patch byte at address ADDR to an INT3 (0xCC) instruction or the equivalent software breakpoint for ARM. Usage: int3 ADDR end define rint3 if $ARM == 1 set *(unsigned int *)$ORIGINAL_INT3ADDRESS = $ORIGINAL_INT3 set $pc = $ORIGINAL_INT3ADDRESS else set *(unsigned char *)$ORIGINAL_INT3ADDRESS = $ORIGINAL_INT3 if sizeof(void *) == 8 set $rip = $ORIGINAL_INT3ADDRESS else set $eip = $ORIGINAL_INT3ADDRESS end end end document rint3 Restore the original byte previous to int3 patch issued with "int3" command. end # ____________________cflow___________________ define print_insn_type if $argc != 1 help print_insn_type else if ($arg0 < 0 || $arg0 > 5) printf "UNDEFINED/WRONG VALUE" end if ($arg0 == 0) printf "UNKNOWN" end if ($arg0 == 1) printf "JMP" end if ($arg0 == 2) printf "JCC" end if ($arg0 == 3) printf "CALL" end if ($arg0 == 4) printf "RET" end if ($arg0 == 5) printf "INT" end end end document print_insn_type Print human-readable mnemonic for the instruction type (usually $INSN_TYPE). Usage: print_insn_type INSN_TYPE_NUMBER end define get_insn_type if $argc != 1 help get_insn_type else set $INSN_TYPE = 0 set $_byte1 = *(unsigned char *)$arg0 if ($_byte1 == 0x9A || $_byte1 == 0xE8) # "call" set $INSN_TYPE = 3 end if ($_byte1 >= 0xE9 && $_byte1 <= 0xEB) # "jmp" set $INSN_TYPE = 1 end if ($_byte1 >= 0x70 && $_byte1 <= 0x7F) # "jcc" set $INSN_TYPE = 2 end if ($_byte1 >= 0xE0 && $_byte1 <= 0xE3 ) # "jcc" set $INSN_TYPE = 2 end if ($_byte1 == 0xC2 || $_byte1 == 0xC3 || $_byte1 == 0xCA || \ $_byte1 == 0xCB || $_byte1 == 0xCF) # "ret" set $INSN_TYPE = 4 end if ($_byte1 >= 0xCC && $_byte1 <= 0xCE) # "int" set $INSN_TYPE = 5 end if ($_byte1 == 0x0F ) # two-byte opcode set $_byte2 = *(unsigned char *)($arg0 + 1) if ($_byte2 >= 0x80 && $_byte2 <= 0x8F) # "jcc" set $INSN_TYPE = 2 end end if ($_byte1 == 0xFF) # opcode extension set $_byte2 = *(unsigned char *)($arg0 + 1) set $_opext = ($_byte2 & 0x38) if ($_opext == 0x10 || $_opext == 0x18) # "call" set $INSN_TYPE = 3 end if ($_opext == 0x20 || $_opext == 0x28) # "jmp" set $INSN_TYPE = 1 end end end end document get_insn_type Recognize instruction type at address ADDR. Take address ADDR and set the global $INSN_TYPE variable to 0, 1, 2, 3, 4, 5 if the instruction at that address is unknown, a jump, a conditional jump, a call, a return, or an interrupt. Usage: get_insn_type ADDR end define step_to_call set $_saved_ctx = $SHOW_CONTEXT set $SHOW_CONTEXT = 0 set $SHOW_NEST_INSN = 0 set logging file /dev/null set logging redirect on set logging on set $_cont = 1 while ($_cont > 0) stepi get_insn_type $pc if ($INSN_TYPE == 3) set $_cont = 0 end end set logging off if ($_saved_ctx > 0) context end set $SHOW_CONTEXT = $_saved_ctx set $SHOW_NEST_INSN = 0 set logging file ~/gdb.txt set logging redirect off set logging on printf "step_to_call command stopped at:\n " x/i $pc printf "\n" set logging off end document step_to_call Single step until a call instruction is found. Stop before the call is taken. Log is written into the file ~/gdb.txt. end define trace_calls printf "Tracing...please wait...\n" set $_saved_ctx = $SHOW_CONTEXT set $SHOW_CONTEXT = 0 set $SHOW_NEST_INSN = 0 set $_nest = 1 set listsize 0 set logging overwrite on set logging file ~/gdb_trace_calls.txt set logging on set logging off set logging overwrite off while ($_nest > 0) get_insn_type $pc # handle nesting if ($INSN_TYPE == 3) set $_nest = $_nest + 1 else if ($INSN_TYPE == 4) set $_nest = $_nest - 1 end end # if a call, print it if ($INSN_TYPE == 3) set logging file ~/gdb_trace_calls.txt set logging redirect off set logging on set $x = $_nest - 2 while ($x > 0) printf "\t" set $x = $x - 1 end x/i $pc end set logging off set logging file /dev/null set logging redirect on set logging on stepi set logging redirect off set logging off end set $SHOW_CONTEXT = $_saved_ctx set $SHOW_NEST_INSN = 0 printf "Done, check ~/gdb_trace_calls.txt\n" end document trace_calls Create a runtime trace of the calls made by target. Log overwrites(!) the file ~/gdb_trace_calls.txt. end define trace_run printf "Tracing...please wait...\n" set $_saved_ctx = $SHOW_CONTEXT set $SHOW_CONTEXT = 0 set $SHOW_NEST_INSN = 1 set logging overwrite on set logging file ~/gdb_trace_run.txt set logging redirect on set logging on set $_nest = 1 while ( $_nest > 0 ) get_insn_type $pc # jmp, jcc, or cll if ($INSN_TYPE == 3) set $_nest = $_nest + 1 else # ret if ($INSN_TYPE == 4) set $_nest = $_nest - 1 end end stepi end printf "\n" set $SHOW_CONTEXT = $_saved_ctx set $SHOW_NEST_INSN = 0 set logging redirect off set logging off # clean up trace file shell grep -v ' at ' ~/gdb_trace_run.txt > ~/gdb_trace_run.1 shell grep -v ' in ' ~/gdb_trace_run.1 > ~/gdb_trace_run.txt shell rm -f ~/gdb_trace_run.1 printf "Done, check ~/gdb_trace_run.txt\n" end document trace_run Create a runtime trace of target. Log overwrites(!) the file ~/gdb_trace_run.txt. end #define ptraceme # catch syscall ptrace # commands # if (sizeof(void *) == 4) # if ($ebx == 0) # set $eax = 0 # continue # end # else # if ($rdi == 0) # set $rax = 0 # continue # end # end # end # set $ptrace_bpnum = $bpnum #end #document ptraceme #Hook ptrace to bypass PTRACE_TRACEME anti debugging technique #end define rptraceme if ($ptrace_bpnum != 0) delete $ptrace_bpnum set $ptrace_bpnum = 0 end end document rptraceme Remove ptrace hook. end # ____________________misc____________________ define hook-stop # Display instructions formats if $ARM == 1 if $ARMOPCODES == 1 set arm show-opcode-bytes 1 else set arm show-opcode-bytes 1 end else if $X86FLAVOR == 0 set disassembly-flavor intel else set disassembly-flavor att end end # this makes 'context' be called at every BP/step if ($SHOW_CONTEXT > 0) context end if ($SHOW_NEST_INSN > 0) set $x = $_nest while ($x > 0) printf "\t" set $x = $x - 1 end end end document hook-stop !!! FOR INTERNAL USE ONLY - DO NOT CALL !!! end # original by Tavis Ormandy (http://my.opera.com/taviso/blog/index.dml/tag/gdb) (great fix!) # modified to work with Mac OS X by fG! # seems nasm shipping with Mac OS X has problems accepting input from stdin or heredoc # input is read into a variable and sent to a temporary file which nasm can read define assemble # dont enter routine again if user hits enter dont-repeat if ($argc) if (*$arg0 = *$arg0) # check if we have a valid address by dereferencing it, # if we havnt, this will cause the routine to exit. end printf "Instructions will be written to %#x.\n", $arg0 else printf "Instructions will be written to stdout.\n" end printf "Type instructions, one per line." color_bold printf " Do not forget to use NASM assembler syntax!\n" color_reset printf "End with a line saying just \"end\".\n" if ($argc) if (sizeof(void *) == 8) # argument specified, assemble instructions into memory at address specified. shell ASMOPCODE="$(while read -ep '>' r && test "$r" != end ; do echo -E "$r"; done)" ; GDBASMFILENAME=$RANDOM; \ echo -e "BITS 64\n$ASMOPCODE" >/tmp/$GDBASMFILENAME ; /usr/local/bin/nasm -f bin -o /dev/stdout /tmp/$GDBASMFILENAME | /usr/bin/hexdump -ve '1/1 "set *((unsigned char *) $arg0 + %#2_ax) = %#02x\n"' >/tmp/gdbassemble ; /bin/rm -f /tmp/$GDBASMFILENAME source /tmp/gdbassemble # all done. clean the temporary file shell /bin/rm -f /tmp/gdbassemble else # argument specified, assemble instructions into memory at address specified. shell ASMOPCODE="$(while read -ep '>' r && test "$r" != end ; do echo -E "$r"; done)" ; GDBASMFILENAME=$RANDOM; \ echo -e "BITS 32\n$ASMOPCODE" >/tmp/$GDBASMFILENAME ; /usr/bin/nasm -f bin -o /dev/stdout /tmp/$GDBASMFILENAME | /usr/bin/hexdump -ve '1/1 "set *((unsigned char *) $arg0 + %#2_ax) = %#02x\n"' >/tmp/gdbassemble ; /bin/rm -f /tmp/$GDBASMFILENAME source /tmp/gdbassemble # all done. clean the temporary file shell /bin/rm -f /tmp/gdbassemble end else if (sizeof(void *) == 8) # no argument, assemble instructions to stdout shell ASMOPCODE="$(while read -ep '>' r && test "$r" != end ; do echo -E "$r"; done)" ; GDBASMFILENAME=$RANDOM; \ echo -e "BITS 64\n$ASMOPCODE" >/tmp/$GDBASMFILENAME ; /usr/local/bin/nasm -f bin -o /dev/stdout /tmp/$GDBASMFILENAME | /usr/local/bin/ndisasm -i -b64 /dev/stdin ; \ /bin/rm -f /tmp/$GDBASMFILENAME else # no argument, assemble instructions to stdout shell ASMOPCODE="$(while read -ep '>' r && test "$r" != end ; do echo -E "$r"; done)" ; GDBASMFILENAME=$RANDOM; \ echo -e "BITS 32\n$ASMOPCODE" >/tmp/$GDBASMFILENAME ; /usr/bin/nasm -f bin -o /dev/stdout /tmp/$GDBASMFILENAME | /usr/bin/ndisasm -i -b32 /dev/stdin ; \ /bin/rm -f /tmp/$GDBASMFILENAME end end end document assemble Assemble instructions using nasm. Type a line containing "end" to indicate the end. If an address is specified, insert/modify instructions at that address. If no address is specified, assembled instructions are printed to stdout. Use the pseudo instruction "org ADDR" to set the base address. end define asm if $argc == 1 assemble $arg0 else assemble end end document asm Shortcut to the asssemble command. end define assemble_gas printf "\nType code to assemble and hit Ctrl-D when finished.\n" printf "You must use GNU assembler (AT&T) syntax.\n" shell filename=$(mktemp); \ binfilename=$(mktemp); \ echo -e "Writing into: ${filename}\n"; \ cat > $filename; echo ""; \ as -o $binfilename < $filename; \ objdump -d -j .text $binfilename; \ rm -f $binfilename; \ rm -f $filename; \ echo -e "temporaly files deleted.\n" end document assemble_gas Assemble instructions to binary opcodes. Uses GNU as and objdump. Usage: assemble_gas end define dump_hexfile dump ihex memory $arg0 $arg1 $arg2 end document dump_hexfile Write a range of memory to a file in Intel ihex (hexdump) format. The range is specified by ADDR1 and ADDR2 addresses. Usage: dump_hexfile FILENAME ADDR1 ADDR2 end define dump_binfile dump memory $arg0 $arg1 $arg2 end document dump_binfile Write a range of memory to a binary file. The range is specified by ADDR1 and ADDR2 addresses. Usage: dump_binfile FILENAME ADDR1 ADDR2 end define dumpmacho if $argc != 2 help dumpmacho end set $headermagic = *$arg0 # the || operator isn't working as it should, wtf!!! if $headermagic != 0xfeedface if $headermagic != 0xfeedfacf printf "[Error] Target address doesn't contain a valid Mach-O binary!\n" help dumpmacho end end set $headerdumpsize = *($arg0+0x14) if $headermagic == 0xfeedface dump memory $arg1 $arg0 ($arg0+0x1c+$headerdumpsize) end if $headermagic == 0xfeedfacf dump memory $arg1 $arg0 ($arg0+0x20+$headerdumpsize) end end document dumpmacho Dump the Mach-O header to a file. You need to input the start address (use info shared command to find it). Usage: dumpmacho STARTADDRESS FILENAME end define cls shell clear end document cls Clear screen. end define search set $start = (char *) $arg0 set $end = (char *) $arg1 set $pattern = (short) $arg2 set $p = $start while $p < $end if (*(short *) $p) == $pattern printf "pattern 0x%hx found at 0x%x\n", $pattern, $p end set $p++ end end document search Search for the given pattern beetween $start and $end address. Usage: search end # _________________user tips_________________ # The 'tips' command is used to provide tutorial-like info to the user define tips printf "Tip Topic Commands:\n" printf "\ttip_display : Automatically display values on each break\n" printf "\ttip_patch : Patching binaries\n" printf "\ttip_strip : Dealing with stripped binaries\n" printf "\ttip_syntax : AT&T vs Intel syntax\n" end document tips Provide a list of tips from users on various topics. end define tip_patch printf "\n" printf " PATCHING MEMORY\n" printf "Any address can be patched using the 'set' command:\n" printf "\t`set ADDR = VALUE` \te.g. `set *0x8049D6E = 0x90`\n" printf "\n" printf " PATCHING BINARY FILES\n" printf "Use `set write` in order to patch the target executable\n" printf "directly, instead of just patching memory\n" printf "\t`set write on` \t`set write off`\n" printf "Note that this means any patches to the code or data segments\n" printf "will be written to the executable file\n" printf "When either of these commands has been issued,\n" printf "the file must be reloaded.\n" printf "\n" end document tip_patch Tips on patching memory and binary files. end define tip_strip printf "\n" printf " STOPPING BINARIES AT ENTRY POINT\n" printf "Stripped binaries have no symbols, and are therefore tough to\n" printf "start automatically. To debug a stripped binary, use\n" printf "\tinfo file\n" printf "to get the entry point of the file\n" printf "The first few lines of output will look like this:\n" printf "\tSymbols from '/tmp/a.out'\n" printf "\tLocal exec file:\n" printf "\t `/tmp/a.out', file type elf32-i386.\n" printf "\t Entry point: 0x80482e0\n" printf "Use this entry point to set an entry point:\n" printf "\t`tbreak *0x80482e0`\n" printf "The breakpoint will delete itself after the program stops as\n" printf "the entry point\n" printf "\n" end document tip_strip Tips on dealing with stripped binaries. end define tip_syntax printf "\n" printf "\t INTEL SYNTAX AT&T SYNTAX\n" printf "\tmnemonic dest, src, imm mnemonic src, dest, imm\n" printf "\t[base+index*scale+disp] disp(base, index, scale)\n" printf "\tregister: eax register: %%eax\n" printf "\timmediate: 0xFF immediate: $0xFF\n" printf "\tdereference: [addr] dereference: addr(,1)\n" printf "\tabsolute addr: addr absolute addr: *addr\n" printf "\tbyte insn: mov byte ptr byte insn: movb\n" printf "\tword insn: mov word ptr word insn: movw\n" printf "\tdword insn: mov dword ptr dword insn: movd\n" printf "\tfar call: call far far call: lcall\n" printf "\tfar jump: jmp far far jump: ljmp\n" printf "\n" printf "Note that order of operands in reversed, and that AT&T syntax\n" printf "requires that all instructions referencing memory operands \n" printf "use an operand size suffix (b, w, d, q)\n" printf "\n" end document tip_syntax Summary of Intel and AT&T syntax differences. end define tip_display printf "\n" printf "Any expression can be set to automatically be displayed every time\n" printf "the target stops. The commands for this are:\n" printf "\t`display expr' : automatically display expression 'expr'\n" printf "\t`display' : show all displayed expressions\n" printf "\t`undisplay num' : turn off autodisplay for expression # 'num'\n" printf "Examples:\n" printf "\t`display/x *(int *)$esp` : print top of stack\n" printf "\t`display/x *(int *)($ebp+8)` : print first parameter\n" printf "\t`display (char *)$esi` : print source string\n" printf "\t`display (char *)$edi` : print destination string\n" printf "\n" end document tip_display Tips on automatically displaying values when a program stops. end # bunch of semi-useless commands # enable and disable shortcuts for stop-on-solib-events fantastic trick! define enablesolib set stop-on-solib-events 1 printf "Stop-on-solib-events is enabled!\n" end document enablesolib Shortcut to enable stop-on-solib-events trick. end define disablesolib set stop-on-solib-events 0 printf "Stop-on-solib-events is disabled!\n" end document disablesolib Shortcut to disable stop-on-solib-events trick. end # enable commands for different displays define enableobjectivec set $SHOWOBJECTIVEC = 1 end document enableobjectivec Enable display of objective-c information in the context window. end define enablecpuregisters set $SHOWCPUREGISTERS = 1 end document enablecpuregisters Enable display of cpu registers in the context window. end define enablestack set $SHOWSTACK = 1 end document enablestack Enable display of stack in the context window. end define enabledatawin set $SHOWDATAWIN = 1 end document enabledatawin Enable display of data window in the context window. end # disable commands for different displays define disableobjectivec set $SHOWOBJECTIVEC = 0 end document disableobjectivec Disable display of objective-c information in the context window. end define disablecpuregisters set $SHOWCPUREGISTERS = 0 end document disablecpuregisters Disable display of cpu registers in the context window. end define disablestack set $SHOWSTACK = 0 end document disablestack Disable display of stack information in the context window. end define disabledatawin set $SHOWDATAWIN = 0 end document disabledatawin Disable display of data window in the context window. end define arm if $ARMOPCODES == 1 set arm show-opcode-bytes 1 else set arm show-opcode-bytes 1 end set $ARM = 1 end document arm Set gdb to work with ARM binaries. end define enablelib set stop-on-solib-events 1 end document enablelib Activate stop-on-solib-events. end define disablelib set stop-on-solib-events 0 end document disablelib Deactivate stop-on-solib-events. end define intelsyntax if $ARM == 0 set disassembly-flavor intel set $X86FLAVOR = 0 end end document intelsyntax Change disassembly syntax to intel flavor. end define attsyntax if $ARM == 0 set disassembly-flavor att set $X86FLAVOR = 1 end end document attsyntax Change disassembly syntax to at&t flavor. end define kernel32 # try to load kgmacros files # failure is silent... source /Volumes/KernelDebugKit/kgmacros set architecture i386 if $argc == 1 target remote localhost:$arg0 else target remote localhost:8832 end end document kernel32 Attach to VMware gdb stub for 32 bits kernel. Add a parameter if you wish to debug another kernel port. VMware increments the port for each running VM with gdb stub. Default without parameters is port 8832. end define kernel64 # try to load kgmacros files # failure is silent... source /Volumes/KernelDebugKit/kgmacros set architecture i386:x86-64 if $argc == 1 target remote localhost:$arg0 else target remote localhost:8864 end end document kernel64 Attach to VMware gdb stub for 64 bits kernel. Add a parameter if you wish to debug another kernel port. VMware increments the port for each running VM with gdb stub. Default without parameters is port 8864. end #EOF # Older change logs: # # Version 7.4.4 (02/01/2012) # - Added the "skip" command. This will jump to the next instruction after EIP/RIP without executing the current one. # Thanks to @bSr43 for the tip to retrieve the current instruction size. # # Version 7.4.3 (04/11/2011) # - Modified "hexdump" command to support a variable number of lines (optional parameter) # - Removed restrictions on type of addresses in the "dd" command - Thanks to Plouj for the warning :-) # I don't know what was the original thinking behind those :-) # - Modified the assemble command to support 64bits - You will need to recompile nasm since the version shipped with OS X doesn't supports 64bits (www.nasm.us). # Assumes that the new binary is installed at /usr/local/bin - modify the variable at the top if you need so. # It will assemble based on the target arch being debugged. If you want to use gdb for a quick asm just use the 32bits or 64bits commands to set your target. # Thanks to snare for the warning and original patch :-) # - Added "asm" command - it's a shortcut to the "assemble" command. # - Added configuration variable for colorized prompt. Plouj reported some issues with Ubuntu's gdb 7.2 if prompt is colorized. # # Version 7.4.2 (11/08/2011) # Small fix to a weird bug happening on FreeBSD 8.2. It doesn't like a "if(" instruction, needs to be "if (". Weird! # Many thanks to Evan for reporting and sending the patch :-) # Added the ptraceme/rptraceme commands to bypass PTRACE_TRACME anti-debugging technique. # Grabbed this from http://falken.tuxfamily.org/?p=171 # It's commented out due to a gdb problem in OS X (refer to http://reverse.put.as/2011/08/20/another-patch-for-apples-gdb-the-definecommands-problem/ ) # Just uncomment it if you want to use in ptrace enabled systems. # # Version 7.4.1 (21/06/2011) - fG! # Added patch sent by sbz, more than 1 year ago, which I forgot to add :-/ # This will allow to search for a given pattern between start and end address. # On sbz words: "It's usefull to find call, ret or everything like that." :-) # New command is "search" # # Version 7.4 (20/06/2011) - fG! # When registers change between instructions the colour will change to red (like it happens in OllyDBG) # This is the default behavior, if you don't like it, modify the variable SHOWREGCHANGES # Added patch sent by Philippe Langlois # Colour the first disassembly line - change the setting below on SETCOLOUR1STLINE - by default it's disabled # # Version 7.3.2 (21/02/2011) - fG! # Added the command rint3 and modified the int3 command. The new command will restore the byte in previous int3 patch. # # Version 7.3.1 (29/06/2010) - fG! # Added enablelib/disablelib command to quickly set the stop-on-solib-events trick # Implemented the stepoh command equivalent to the stepo but using hardware breakpoints # More fixes to stepo # # Version 7.3 (16/04/2010) - fG! # Support for 64bits targets. Default is 32bits, you should modify the variable or use the 32bits or 64bits to choose the mode. # I couldn't find another way to recognize the type of binary… Testing the register doesn't work that well. # TODO: fix objectivec messages and stepo for 64bits # Version 7.2.1 (24/11/2009) - fG! # Another fix to stepo (0xFF92 missing) # # Version 7.2 (11/10/2009) - fG! # Added the smallregisters function to create 16 and 8 bit versions from the registers EAX, EBX, ECX, EDX # Revised and fixed all the dumpjump stuff, following Intel manuals. There were some errors (thx to rev who pointed the jle problem). # Small fix to stepo command (missed a few call types) # # Version 7.1.7 - fG! # Added the possibility to modify what's displayed with the context window. You can change default options at the gdb options part. For example, kernel debugging is much slower if the stack display is enabled... # New commands enableobjectivec, enablecpuregisters, enablestack, enabledatawin and their disable equivalents (to support realtime change of default options) # Fixed problem with the assemble command. I was calling /bin/echo which doesn't support the -e option ! DUH ! Should have used bash internal version. # Small fixes to colours... # New commands enablesolib and disablesolib . Just shortcuts for the stop-on-solib-events fantastic trick ! Hey... I'm lazy ;) # Fixed this: Possible removal of "u" command, info udot is missing in gdb 6.8-debian . Doesn't exist on OS X so bye bye !!! # Displays affected flags in jump decisions # # Version 7.1.6 - fG! # Added modified assemble command from Tavis Ormandy (further modified to work with Mac OS X) (shell commands used use full path name, working for Leopard, modify for others if necessary) # Renamed thread command to threads because thread is an internal gdb command that allows to move between program threads # # Version 7.1.5 (04/01/2009) - fG! # Fixed crash on Leopard ! There was a If Else condition where the else had no code and that made gdb crash on Leopard (CRAZY!!!!) # Better code indention # # Version 7.1.4 (02/01/2009) - fG! # Bug in show objective c messages with Leopard ??? # Nop routine support for single address or range (contribution from gln [ghalen at hack.se]) # Used the same code from nop to null routine # # Version 7.1.3 (31/12/2008) - fG! # Added a new command 'stepo'. This command will step a temporary breakpoint on next instruction after the call, so you can skip over # the call. Did this because normal commands not always skip over (mainly with objc_msgSend) # # Version 7.1.2 (31/12/2008) - fG! # Support for the jump decision (will display if a conditional jump will be taken or not) # # Version 7.1.1 (29/12/2008) - fG! # Moved gdb options to the beginning (makes more sense) # Added support to dump message being sent to msgSend (easier to understand what's going on) # # Version 7.1 # Fixed serious (and old) bug in dd and datawin, causing dereference of # obviously invalid address. See below: # gdb$ dd 0xffffffff # FFFFFFFF : Cannot access memory at address 0xffffffff # # Version 7.0 # Added cls command. # Improved documentation of many commands. # Removed bp_alloc, was neither portable nor usefull. # Checking of passed argument(s) in these commands: # contextsize-stack, contextsize-data, contextsize-code # bp, bpc, bpe, bpd, bpt, bpm, bhb,... # Fixed bp and bhb inconsistencies, look at * signs in Version 6.2 # Bugfix in bhb command, changed "break" to "hb" command body # Removed $SHOW_CONTEXT=1 from several commands, this variable # should only be controlled globally with context-on and context-off # Improved stack, func, var and sig, dis, n, go,... # they take optional argument(s) now # Fixed wrong $SHOW_CONTEXT assignment in context-off # Fixed serious bug in cft command, forgotten ~ sign # Fixed these bugs in step_to_call: # 1) the correct logging sequence is: # set logging file > set logging redirect > set logging on # 2) $SHOW_CONTEXT is now correctly restored from $_saved_ctx # Fixed these bugs in trace_calls: # 1) the correct logging sequence is: # set logging file > set logging overwrite > # set logging redirect > set logging on # 2) removed the "clean up trace file" part, which is not needed now, # stepi output is properly redirected to /dev/null # 3) $SHOW_CONTEXT is now correctly restored from $_saved_ctx # Fixed bug in trace_run: # 1) $SHOW_CONTEXT is now correctly restored from $_saved_ctx # Fixed print_insn_type -- removed invalid semicolons!, wrong value checking, # Added TODO entry regarding the "u" command # Changed name from gas_assemble to assemble_gas due to consistency # Output from assemble and assemble_gas is now similar, because i made # both of them to use objdump, with respect to output format (AT&T|Intel). # Whole code was checked and made more consistent, readable/maintainable. # # Version 6.2 # Add global variables to allow user to control stack, data and code window sizes # Increase readability for registers # Some corrections (hexdump, ddump, context, cfp, assemble, gas_asm, tips, prompt) # # Version 6.1-color-user # Took the Gentoo route and ran sed s/user/user/g # # Version 6.1-color # Added color fixes from # http://gnurbs.blogsome.com/2006/12/22/colorizing-mamons-gdbinit/ # # Version 6.1 # Fixed filename in step_to_call so it points to /dev/null # Changed location of logfiles from /tmp to ~ # # Version 6 # Added print_insn_type, get_insn_type, context-on, context-off commands # Added trace_calls, trace_run, step_to_call commands # Changed hook-stop so it checks $SHOW_CONTEXT variable # # Version 5 # Added bpm, dump_bin, dump_hex, bp_alloc commands # Added 'assemble' by elaine, 'gas_asm' by mong # Added Tip Topics for aspiring users ;) # # Version 4 # Added eflags-changing insns by pusillus # Added bp, nop, null, and int3 patch commands, also hook-stop # # Version 3 # Incorporated elaine's if/else goodness into the hex/ascii dump # # Version 2 # Radix bugfix by elaine