Skip to content

add Autoskip mode #2

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
theAlexes wants to merge 5 commits into
base: main
Choose a base branch
from
Open

add Autoskip mode #2

Changes from all commits
Commits
Show all changes
5 commits
Select commit Hold shift + click to select a range
801362d
factor out the dump-line generation
Jun 26, 2024
7314183
implement a somewhat-workable autoskip mode
Jun 26, 2024
f493059
fix up some textual nitpicks
Jun 26, 2024
ec9c140
fix up alternating between all-nulls and not-all-nulls
Jun 26, 2024
d597105
force autoskip mode off when doing a postscript dump (immiscible opti…
Jun 26, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
67 changes: 48 additions & 19 deletions yxd.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -7,6 +7,7 @@
parser = argparse.ArgumentParser(description="yxd - Yuu's heX Dumper")
parser.add_argument('-f', help='File to open', dest='inFile')
parser.add_argument('input', help='File to open', nargs='?')
parser.add_argument('-a', help='Autoskip mode', dest='autoSkip', action="store_true")
parser.add_argument('-o', help='Offset to start within file', dest='startOffset', type=lambda x: int(x,0) )
parser.add_argument('-s', help='Size of buffer to dump', dest='bufferSize', type=lambda x: int(x,0) )
parser.add_argument('-r', help='Do a reverse hex dump', dest='reverseDump', action="store_true")
Expand All @@ -18,7 +19,7 @@
parser.add_argument('--style', help='Show Current Hex Style', dest='dumpStyle', action="store_true")
parser.add_argument('-v', help='Print Version Info', dest='printVersion', action="store_true")

versionInfo="yxd - Yuu's heX Dumper Version 20230831.0"""
versionInfo="yxd - Yuu's heX Dumper Version 20230831.0"

def styleDump():
"""
Expand All @@ -34,7 +35,18 @@ def styleDump():
else:
print()

def dump(inBytes,baseAddr=0,dataLen=0,blockSize=16,outFormat="xxd",quiet=False):
def makeDumpLine(outFormat, hexOut, offsetOut, bAsc):
"""
Produce an output line of the given format.
"""
if outFormat == "xx":
return f"{hexOut}; {offsetOut}{bAsc}\n"
elif outFormat == "ps":
return "".join(hexOut.split())
else:
return f"{offsetOut}{hexOut}{bAsc}\n"

def dump(inBytes,baseAddr=0,dataLen=0,blockSize=16,outFormat="xxd",quiet=False,autoSkip=False):
"""
Dump hex.

Expand All @@ -55,21 +67,25 @@ def dump(inBytes,baseAddr=0,dataLen=0,blockSize=16,outFormat="xxd",quiet=False):
The format of hex dump format to do
quiet : bool
If true, don't print the output to the terminal
autoSkip : bool
If true, skip lines of nulls.
Returns
-------
hexDumpOut : str
The text form of the hex dump
"""
dataLen = len(inBytes) if ( dataLen == 0 ) or ( dataLen > len(inBytes) ) else dataLen # Sanity check
offs = 0
hexDumpOut = ""
hexDumpOut = ""
# Style
dumpBytez = yc.bytez
dumpOffstyle = yc.OFFSTYLE
dumpSEP0 = yc.SEP0
dumpSEP1 = yc.SEP1
dumpSEP2 = yc.SEP2
dumpEOA = yc.EOA
lastChunk = None
autoSkipped = lastChunkAllNulls = thisChunkAllNulls = False
if ( outFormat == "xxd" ) or ( outFormat == "xx" ) or ( outFormat == "ps" ):
dumpBytez = {}
dumpOffstyle = ""
Expand All @@ -81,7 +97,15 @@ def dump(inBytes,baseAddr=0,dataLen=0,blockSize=16,outFormat="xxd",quiet=False):
try:
hb = []
bAsc = ""
if autoSkip and lastChunk is not None and all(x == 0 for x in lastChunk):
lastChunkAllNulls = True
else:
lastChunkAllNulls = False
bChunk = inBytes[offs:offs+blockSize]
if autoSkip and all(x == 0 for x in bChunk) and len(bChunk) == blockSize:
thisChunkAllNulls = True
else:
thisChunkAllNulls = False
chunkBytes = 0
for b in bChunk:
bFmt = f"{dumpBytez[b]}" if b in dumpBytez.keys() else ""
Expand All @@ -103,19 +127,22 @@ def dump(inBytes,baseAddr=0,dataLen=0,blockSize=16,outFormat="xxd",quiet=False):
hexOut += f"{hb[10]}{hb[11]} "
hexOut += f"{hb[12]}{hb[13]} "
hexOut += f"{hb[14]}{hb[15]}{dumpSEP2}"
if outFormat == "xx":
if quiet == False:
print(f"{hexOut}; {offsetOut}{bAsc}")
hexDumpOut += f"{hexOut}; {offsetOut}{bAsc}\n"
elif outFormat == "ps":
if quiet == False:
print("".join(hexOut.split()),end="")
hexDumpOut += "".join(hexOut.split())
else:
if quiet == False:
print(f"{offsetOut}{hexOut}{bAsc}")
hexDumpOut += f"{offsetOut}{hexOut}{bAsc}\n"
line = makeDumpLine(outFormat, hexOut, offsetOut, bAsc)
if not autoSkip and not quiet:
print(line, end="") # the line comes from makeDumpLine with a newline if it needs one
elif not quiet:
if lastChunk is None:
print(line, end="")
elif lastChunkAllNulls and thisChunkAllNulls:
if not autoSkipped:
print("*")
autoSkipped = True
else:
autoSkipped = False
print(line, end="")
hexDumpOut += line
offs = offs + blockSize
lastChunk = bChunk
except Exception as e:
print(f"yxd.dump: {e}")
if outFormat == "ps":
Expand Down Expand Up @@ -299,7 +326,7 @@ class yxd:
reverseDump():
do a reverse hex dump
"""
def __init__(self, binData, amount=0, baseAddr=0, outFormat="xxd", color="default", blockSize=16, offset=0, quiet=False ):
def __init__(self, binData, amount=0, baseAddr=0, outFormat="xxd", color="default", blockSize=16, offset=0, quiet=False, autoSkip=False):
self.binData = binData
self.dataLen = len(binData)
self.baseAddr = baseAddr
Expand All @@ -309,6 +336,7 @@ def __init__(self, binData, amount=0, baseAddr=0, outFormat="xxd", color="defaul
self.blockSize = blockSize
self.amount = amount
self.quiet = quiet
self.autoSkip = autoSkip
if quiet != True:
self.dump()
def styleDump(self):
Expand All @@ -320,7 +348,7 @@ def styleDump(self):
else:
print()
def dump(self):
return dump(self.binData,self.baseAddr,self.dataLen,self.blockSize,self.outFormat)
return dump(self.binData,self.baseAddr,self.dataLen,self.blockSize,self.outFormat,autoSkip=self.autoSkip)
def genPythonScript(self):
genPythonScript(self.binData)
def genShellcode(self):
Expand All @@ -344,6 +372,7 @@ def main():
if args.xxFormat:
hexStyle = "xx"
if args.psFormat:
args.autoSkip = False
hexStyle = "ps"

bufferSize = args.bufferSize if args.bufferSize else 0
Expand All @@ -360,7 +389,7 @@ def main():
binData = sys.stdin.buffer.read()
binSize = len(binData)

yxdd = yxd(binData, baseAddr=startOffset, outFormat=hexStyle, quiet=True)
yxdd = yxd(binData, baseAddr=startOffset, outFormat=hexStyle, quiet=True, autoSkip=args.autoSkip)
if args.genPythonScript:
yxdd.genPythonScript()
elif args.genShellcode:
Expand All @@ -371,4 +400,4 @@ def main():
yxdd.dump()

if __name__ == '__main__':
main()
main()