AutokeySolver

This commit is contained in:
relikd
2021-01-24 23:44:03 +01:00
parent c2e00a19bd
commit d3cc823268
3 changed files with 89 additions and 72 deletions

View File

@@ -34,7 +34,7 @@ class RuneSolver(RuneRunner):
skip = is_interrupt and self.interrupt_counter in self.INTERRUPT_POS
mark_this = self.mark_char_at(index)
if not skip:
obj = self.cipher(obj, (encrypted_data, index))
obj = self.cipher(obj, (index, encrypted_data))
mark_next = self.mark_char_at(index)
return obj, mark_this, mark_next
@@ -53,65 +53,6 @@ class RuneSolver(RuneRunner):
return txt + f'\ninterrupt jumps: {self.INTERRUPT_POS}'
#########################################
# VigenereSolver : Decrypt runes with key; handle key shift, rotation, etc.
#########################################
class VigenereSolver(RuneSolver):
def __init__(self):
super().__init__()
self.current_key_pos = 0
self.reset()
def reset(self):
super().reset()
self.KEY_DATA = [] # the key material
self.KEY_INVERT = False # ABCD -> ZYXW
self.KEY_SHIFT = 0 # ABCD -> DABC
self.KEY_ROTATE = 0 # ABCD -> ZABC
self.KEY_OFFSET = 0 # ABCD -> __ABCD
self.KEY_POST_PAD = 0 # ABCD -> ABCD__
def run(self, data=None):
self.current_key_pos = 0
super().run(data=data)
def is_key_active(self, _=None):
i = self.current_key_pos - self.KEY_OFFSET
if i >= 0 and i < len(self.KEY_DATA):
return self.KEY_DATA[i] != 29 # used as placeholder for unknown
return False
def mark_char_at(self, position):
return self.is_key_active(position)
def rotate_key(self):
key_size = self.KEY_OFFSET + len(self.KEY_DATA) + self.KEY_POST_PAD
if key_size > 0: # mostly for key invert without a key
self.current_key_pos = (self.current_key_pos + 1) % key_size
def cipher(self, rune, context):
r_idx = rune.index
if self.KEY_INVERT:
r_idx = 28 - r_idx
if self.is_key_active():
key_i = self.current_key_pos
i = (key_i - self.KEY_OFFSET + self.KEY_SHIFT) % len(self.KEY_DATA)
r_idx = (r_idx - self.KEY_DATA[i] - self.KEY_ROTATE) % 29
self.rotate_key()
return Rune(i=r_idx)
def __str__(self):
key = RuneText(self.KEY_DATA).description(indexWhitespace=True)
txt = super().__str__()
txt += f'\nkey: {key}'
txt += f'\nkey invert: {self.KEY_INVERT}'
txt += f'\nkey shift: {self.KEY_SHIFT} indices'
txt += f'\nkey offset: {self.KEY_OFFSET} runes'
txt += f'\nkey post pad: {self.KEY_POST_PAD} runes'
return txt
#########################################
# SequenceSolver : Decrypt runes with sequential function
#########################################
@@ -141,35 +82,106 @@ class SequenceSolver(RuneSolver):
#########################################
# AffineSolver : Decrypt runes with an array of (s, t) affine keys
# RunningKeySolver : Decrypt runes with key; handles shift, rotation, etc.
#########################################
class AffineSolver(RuneSolver):
class RunningKeySolver(RuneSolver):
def __init__(self):
super().__init__()
self.current_key_pos = 0
self.reset()
def reset(self):
super().reset()
self.KEY_DATA = [] # the key material
self.KEY_INVERT = False # ABCD -> ZYXW
self.KEY_SHIFT = 0 # ABCD -> DABC
self.KEY_ROTATE = 0 # ABCD -> ZABC
self.KEY_OFFSET = 0 # ABCD -> __ABCD
self.KEY_POST_PAD = 0 # ABCD -> ABCD__
def run(self, data=None):
self.current_key_pos = 0
self.k_current_pos = 0
self.k_len = len(self.KEY_DATA)
self.k_full_len = self.KEY_OFFSET + self.k_len + self.KEY_POST_PAD
super().run(data=data)
def rotate_key(self):
self.current_key_pos = (self.current_key_pos + 1) % len(self.KEY_DATA)
def mark_char_at(self, position):
return self.active_key_pos() != -1
def active_key_pos(self):
i = self.k_current_pos - self.KEY_OFFSET
if i >= 0 and i < self.k_len:
if self.KEY_DATA[i] != 29: # placeholder for unknown
return i
return -1
def cipher(self, rune, context):
r_idx = rune.index
if self.KEY_INVERT:
r_idx = 28 - r_idx
r_idx = LIB.affine_decrypt(r_idx, self.KEY_DATA[self.current_key_pos])
self.rotate_key()
pos = self.active_key_pos()
if pos != -1:
i = (pos + self.KEY_SHIFT) % self.k_len
r_idx = (self.decrypt(r_idx, i) - self.KEY_ROTATE) % 29
# rotate_key
if self.k_full_len > 0: # e.g., for key invert without a key
self.k_current_pos = (self.k_current_pos + 1) % self.k_full_len
return Rune(i=r_idx)
def decrypt(self, rune_index, key_index):
raise NotImplementedError # must subclass
def key__str__(self):
return self.KEY_DATA # you should override this
def key__str__basic_runes(self):
return RuneText(self.KEY_DATA).description(indexWhitespace=True)
def __str__(self):
return super().__str__() + \
f'\nkey: {self.KEY_DATA}\nkey invert: {self.KEY_INVERT}'
txt = super().__str__()
txt += f'\nkey: {self.key__str__()}'
txt += f'\nkey invert: {self.KEY_INVERT}'
txt += f'\nkey offset: {self.KEY_OFFSET} runes'
txt += f'\nkey post pad: {self.KEY_POST_PAD} runes'
txt += f'\nkey shift: {self.KEY_SHIFT} indices'
txt += f'\nkey rotate: {self.KEY_ROTATE} indices'
return txt
#########################################
# VigenereSolver : Decrypt runes with an array of indices
#########################################
class VigenereSolver(RunningKeySolver):
def decrypt(self, rune_index, key_index):
return rune_index - self.KEY_DATA[key_index]
def key__str__(self):
return self.key__str__basic_runes()
#########################################
# AffineSolver : Decrypt runes with an array of (s, t) affine keys
#########################################
class AffineSolver(RunningKeySolver):
def decrypt(self, rune_index, key_index):
return LIB.affine_decrypt(rune_index, self.KEY_DATA[key_index])
#########################################
# AutokeySolver : Decrypts runes by using previously decrypted ones as input
#########################################
class AutokeySolver(RunningKeySolver):
def run(self, data=None):
self.running_key = self.KEY_DATA[:]
super().run(data=data)
def decrypt(self, rune_index, key_index):
rune_index = (rune_index - self.running_key.pop(0)) % 29
self.running_key.append(rune_index)
return rune_index
def key__str__(self):
return self.key__str__basic_runes()