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#!/usr/bin/env python3
from enochecker import BaseChecker, BrokenServiceException, EnoException, run
from enochecker.utils import SimpleSocket, assert_equals, assert_in
import random, string, struct, logging
import numpy as np
logging.getLogger("faker").setLevel(logging.WARNING)
from faker import Faker
fake = Faker(["en_US"])
class STLDoctorChecker(BaseChecker):
flag_variants = 1
noise_variants = 1
havoc_variants = 4
service_name = "stldoctor"
port = 9000
def login_user(self, conn: SimpleSocket, password: str):
self.debug("Sending command to login.")
conn.write(f"login\n{password}\n")
conn.readline_expect(b"logged in!", read_until=b"$", exception_message="Failed to log in")
def binwrite(conn: SimpleSocket, buf: bytes):
conn.sock.sendall(buf)
def fake_filename(self):
allowed = "abcdefghijklmopqrstuvwxyz0123456789-+.!"
return "".join([c for c in fake.name().lower().replace(" ", "-") if c in allowed][:60]).ljust(5, "!")
def generate_ascii_file(self, solidname: str):
if solidname != "":
content = f"solid {solidname}\n"
else:
content = "solid\n"
facet_count = int(random.random() * 30) + 4
for fi in range(facet_count):
content += "facet normal "
vs = [[random.random() for i in range(3)] for k in range(3)]
norm = np.cross(np.subtract(vs[1], vs[0]), np.subtract(vs[2],vs[0]))
norm = norm / np.linalg.norm(norm)
content += " ".join([f"{v:.2f}" for v in norm]) + "\n"
content += "outer loop\n"
for i in range(3):
content += "vertex " + " ".join([f"{v:.2f}" for v in vs[i]]) + "\n"
content += "endloop\n"
content += "endfacet\n"
if solidname != b"":
content += f"endsolid {solidname}\n"
else:
content += "endsolid\n"
return content.encode("latin1")
def generate_bin_file(self, solidname: str):
if len(solidname.encode()) > 78:
raise EnoException("Solidname to embed in header is larger than header itself")
if solidname != "":
content = b"#" + solidname.encode("ascii").ljust(78, b"\x00") + b"\x00"
else:
content = b"#" + b"\x00" * 79
facet_count = int(random.random() * 30) + 4
content += struct.pack("<I", facet_count)
for fi in range(facet_count):
vs = [[random.random() for i in range(3)] for k in range(3)]
norm = np.cross(np.subtract(vs[1], vs[0]), np.subtract(vs[2],vs[0]))
for i in range(3):
content += struct.pack("<f", norm[i])
for k in range(3):
for i in range(3):
content += struct.pack("<f", vs[k][i])
content += b"\x00\x00"
return content
def generate_file(self, filetype: str, solidname: str):
if filetype == "ascii":
return self.generate_ascii_file(solidname = solidname)
elif filetype == "bin":
return self.generate_bin_file(solidname = solidname)
else:
raise EnoException("Invalid file type supplied");
def putfile(self, conn: SimpleSocket, solidname: str, modelname: str, filetype: str):
# Generate file contents
stlfile = self.generate_file(filetype = filetype, solidname = solidname)
# Upload file
self.debug("Sending command to submit file")
conn.write("submit\n")
conn.write(f"{len(stlfile)}\n")
binwrite(conn, stlfile)
conn.write(f"{modelname}\n")
self.debug(b":::RESPONSE:::\n" + conn.read_until(b"with ID "))
# Parse ID
fileid = conn.read_until(b"!")
if fileid == b"":
raise BrokenServiceException("Unable to upload file!")
self.debug(f"Got ID {fileid}")
conn.read_until(b"$")
return stlfile, fileid
def getfile(self, conn: SimpleSocket, modelname: str):
if modelname != "":
self.debug(f"Sending command to retrieve file with '{modelname}'")
conn.write(f"query\n{modelname}\n0\ny\n")
else:
self.debug(f"Sending command to retrieve file")
conn.write(f"query\n0\ny\n")
resp = conn.read_until(b"$")
return resp
def querydb(self, *args):
self.debug("Querying db contents");
vals = []
for arg in args:
try:
val: str = self.chain_db[arg]
except IndexError as ex:
raise BrokenServiceException("Invalid db contents")
vals.append(val)
return vals
def postdb(self, vdict):
self.chain_db = vdict
def havoc_upload(self, filetype: str, registered: bool):
conn = self.openconn()
if registered:
pass # TODO: auth
modelname = self.fake_filename()[:50]
modelname += "".join([chr(127 + int(random.random() * 128)) for i in range(10)]) # noise
contents, mid = self.putfile(conn, filetype = filetype, modelname = modelname, solidname = self.fake_filename())
resp = self.getfile(conn, modelname = modelname)
assert_in(modelname.encode(), resp, f"Model name '{modelname}' not returned / correctly parsed")
assert_in(solidname.encode(), resp, f"Solid name '{modelname}' not returned / correctly parsed")
assert_in(contents, resp, f"STL File contents not returned / correctly parsed")
self.closeconn(conn)
conn = self.openconn()
resp = self.getfile(conn, modelname = modelname)
assert_in(modelname.encode(), resp, f"Model name '{modelname}' not returned / correctly parsed")
assert_in(solidname.encode(), resp, f"Solid name '{modelname}' not returned / correctly parsed")
assert_in(contents, resp, f"STL File contents not returned / correctly parsed")
self.closeconn(conn)
def openconn(self):
self.debug("Connecting to service")
conn = self.connect()
conn.read_until("$") # ignore welcome
return conn
def closeconn(self, conn: SimpleSocket):
self.debug("Sending exit command")
conn.write("exit\n")
conn.close()
def putflag(self): # type: () -> None
if self.variant_id == 0:
conn = self.openconn()
modelname = self.fake_filename()
stlfile, fileid = self.putfile(conn, solidname = self.flag, modelname = modelname, filetype = "ascii")
self.closeconn(conn)
self.postdb({ "fileid": fileid, "modelname": modelname })
else:
raise EnoException("Invalid variant_id provided")
def getflag(self): # type: () -> None
if self.variant_id == 0:
fileid, modelname = self.querydb("fileid", "modelname")
conn = self.openconn()
resp = self.getfile(conn, modelname)
assert_in(self.flag.encode(), resp, "Resulting flag was found to be incorrect")
self.closeconn(conn)
else:
raise EnoException("Invalid variant_id provided")
def putnoise(self): # type: () -> None
if self.variant_id == 0:
conn = self.openconn()
modelname = self.fake_filename()
solidname = self.fake_filename()
contents, fileid = self.putfile(conn, modelname = modelname, solidname = solidname, filetype = "bin")
self.closeconn(conn)
self.postdb({ "fileid": fileid, "modelname": modelname, "solidname": solidname, "contents": contents })
else:
raise EnoException("Invalid variant_id provided")
def getnoise(self): # type: () -> None
if self.variant_id == 0:
fileid, modelname, solidname, contents = self.querydb("fileid", "modelname", "solidname", "contents")
conn = self.openconn()
resp = self.getfile(conn, modelname)
# assert_in(contents, resp, "File content returned by service found to be incorrect")
assert_in(solidname.encode(), resp, "Solid name returned by service found to be incorrect")
assert_in(modelname.encode(), resp, "Model name returned by service found to be incorrect")
self.closeconn(conn)
else:
raise EnoException("Invalid variant_id provided")
def havoc(self): # type: () -> None
if self.variant_id == 0:
self.havoc_upload(filetype = 'ascii', registered = False)
elif self.variant_id == 1:
self.havoc_upload(filetype = 'bin', registered = False)
elif self.variant_id == 2:
self.havoc_upload(filetype = 'ascii', registered = True)
elif self.variant_id == 3:
self.havoc_upload(filetype = 'bin', registered = True)
else:
raise EnoException("Invalid variant_id provided");
# TODO!
conn = self.openconn()
self.closeconn(conn)
def exploit(self):
"""
This method was added for CI purposes for exploits to be tested.
Will (hopefully) not be called during actual CTF.
:raises EnoException on Error
:return This function can return a result if it wants
If nothing is returned, the service status is considered okay.
The preferred way to report Errors in the service is by raising an appropriate EnoException
"""
# TODO: We still haven't decided if we want to use this function or not. TBA
pass
app = STLDoctorChecker.service # This can be used for uswgi.
if __name__ == "__main__":
run(STLDoctorChecker)
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