onionr/onionr/onionrblockapi.py

721 lines
23 KiB
Python
Executable File

'''
Onionr - P2P Anonymous Storage Network
This file contains the OnionrBlocks class which is a class for working with Onionr blocks
'''
'''
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
'''
import core as onionrcore, logger, config, onionrexceptions, nacl.exceptions
import json, os, sys, datetime, base64, onionrstorage
from onionrusers import onionrusers
class Block:
blockCacheOrder = list() # NEVER write your own code that writes to this!
blockCache = dict() # should never be accessed directly, look at Block.getCache()
def __init__(self, hash = None, core = None, type = None, content = None, expire=None, decrypt=False, bypassReplayCheck=False):
# take from arguments
# sometimes people input a bytes object instead of str in `hash`
if (not hash is None) and isinstance(hash, bytes):
hash = hash.decode()
self.hash = hash
self.core = core
self.btype = type
self.bcontent = content
self.expire = expire
self.bypassReplayCheck = bypassReplayCheck
# initialize variables
self.valid = True
self.raw = None
self.signed = False
self.signature = None
self.signedData = None
self.blockFile = None
self.parent = None
self.bheader = {}
self.bmetadata = {}
self.isEncrypted = False
self.decrypted = False
self.signer = None
self.validSig = False
self.autoDecrypt = decrypt
# handle arguments
if self.getCore() is None:
self.core = onionrcore.Core()
self.update()
def decrypt(self, encodedData = True):
'''
Decrypt a block, loading decrypted data into their vars
'''
if self.decrypted:
return True
retData = False
core = self.getCore()
# decrypt data
if self.getHeader('encryptType') == 'asym':
try:
self.bcontent = core._crypto.pubKeyDecrypt(self.bcontent, encodedData=encodedData)
bmeta = core._crypto.pubKeyDecrypt(self.bmetadata, encodedData=encodedData)
try:
bmeta = bmeta.decode()
except AttributeError:
# yet another bytes fix
pass
self.bmetadata = json.loads(bmeta)
self.signature = core._crypto.pubKeyDecrypt(self.signature, encodedData=encodedData)
self.signer = core._crypto.pubKeyDecrypt(self.signer, encodedData=encodedData)
self.bheader['signer'] = self.signer.decode()
self.signedData = json.dumps(self.bmetadata) + self.bcontent.decode()
# Check for replay attacks
try:
if self.core._utils.getEpoch() - self.core.getBlockDate(self.hash) < 60:
assert self.core._crypto.replayTimestampValidation(self.bmetadata['rply'])
except (AssertionError, KeyError) as e:
if not self.bypassReplayCheck:
# Zero out variables to prevent reading of replays
self.bmetadata = {}
self.signer = ''
self.bheader['signer'] = ''
self.signedData = ''
self.signature = ''
raise onionrexceptions.ReplayAttack('Signature is too old. possible replay attack')
try:
assert self.bmetadata['forwardEnc'] is True
except (AssertionError, KeyError) as e:
pass
else:
try:
self.bcontent = onionrusers.OnionrUser(self.getCore(), self.signer).forwardDecrypt(self.bcontent)
except (onionrexceptions.DecryptionError, nacl.exceptions.CryptoError) as e:
logger.error(str(e))
pass
except nacl.exceptions.CryptoError:
pass
#logger.debug('Could not decrypt block. Either invalid key or corrupted data')
except onionrexceptions.ReplayAttack:
logger.warn('%s is possibly a replay attack' % (self.hash,))
else:
retData = True
self.decrypted = True
else:
logger.warn('symmetric decryption is not yet supported by this API')
return retData
def verifySig(self):
'''
Verify if a block's signature is signed by its claimed signer
'''
core = self.getCore()
if core._crypto.edVerify(data=self.signedData, key=self.signer, sig=self.signature, encodedData=True):
self.validSig = True
else:
self.validSig = False
return self.validSig
def update(self, data = None, file = None):
'''
Loads data from a block in to the current object.
Inputs:
- data (str):
- if None: will load from file by hash
- else: will load from `data` string
- file (str):
- if None: will load from file specified in this parameter
- else: will load from wherever block is stored by hash
Outputs:
- (bool): indicates whether or not the operation was successful
'''
try:
# import from string
blockdata = data
# import from file
if blockdata is None:
try:
blockdata = onionrstorage.getData(self.core, self.getHash()).decode()
except AttributeError:
raise onionrexceptions.NoDataAvailable('Block does not exist')
else:
self.blockFile = None
# parse block
self.raw = str(blockdata)
self.bheader = json.loads(self.getRaw()[:self.getRaw().index('\n')])
self.bcontent = self.getRaw()[self.getRaw().index('\n') + 1:]
if ('encryptType' in self.bheader) and (self.bheader['encryptType'] in ('asym', 'sym')):
self.bmetadata = self.getHeader('meta', None)
self.isEncrypted = True
else:
self.bmetadata = json.loads(self.getHeader('meta', None))
self.parent = self.getMetadata('parent', None)
self.btype = self.getMetadata('type', None)
self.signed = ('sig' in self.getHeader() and self.getHeader('sig') != '')
# TODO: detect if signer is hash of pubkey or not
self.signer = self.getHeader('signer', None)
self.signature = self.getHeader('sig', None)
# signed data is jsonMeta + block content (no linebreak)
self.signedData = (None if not self.isSigned() else self.getHeader('meta') + self.getContent())
self.date = self.getCore().getBlockDate(self.getHash())
self.claimedTime = self.getHeader('time', None)
if not self.getDate() is None:
self.date = datetime.datetime.fromtimestamp(self.getDate())
self.valid = True
if len(self.getRaw()) <= config.get('allocations.blockCache', 500000):
self.cache()
if self.autoDecrypt:
self.decrypt()
return True
except Exception as e:
logger.warn('Failed to parse block %s.' % self.getHash(), error = e, timestamp = False)
# if block can't be parsed, it's a waste of precious space. Throw it away.
if not self.delete():
logger.warn('Failed to delete invalid block %s.' % self.getHash(), error = e)
else:
logger.debug('Deleted invalid block %s.' % self.getHash(), timestamp = False)
self.valid = False
return False
def delete(self):
'''
Deletes the block's file and records, if they exist
Outputs:
- (bool): whether or not the operation was successful
'''
if self.exists():
os.remove(self.getBlockFile())
self.getCore().removeBlock(self.getHash())
return True
return False
def save(self, sign = False, recreate = True):
'''
Saves a block to file and imports it into Onionr
Inputs:
- sign (bool): whether or not to sign the block before saving
- recreate (bool): if the block already exists, whether or not to recreate the block and save under a new hash
Outputs:
- (bool): whether or not the operation was successful
'''
try:
if self.isValid() is True:
'''
if (not self.getBlockFile() is None) and (recreate is True):
onionrstorage.store(self.core, self.getRaw().encode())
#with open(self.getBlockFile(), 'wb') as blockFile:
# blockFile.write(self.getRaw().encode())
else:
'''
self.hash = self.getCore().insertBlock(self.getRaw(), header = self.getType(), sign = sign, meta = self.getMetadata(), expire = self.getExpire())
if self.hash != False:
self.update()
return self.getHash()
else:
logger.warn('Not writing block; it is invalid.')
except Exception as e:
logger.error('Failed to save block.', error = e, timestamp = False)
return False
# getters
def getExpire(self):
'''
Returns the expire time for a block
Outputs:
- (int): the expire time for a block, or None
'''
return self.expire
def getHash(self):
'''
Returns the hash of the block if saved to file
Outputs:
- (str): the hash of the block, or None
'''
return self.hash
def getCore(self):
'''
Returns the Core instance being used by the Block
Outputs:
- (Core): the Core instance
'''
return self.core
def getType(self):
'''
Returns the type of the block
Outputs:
- (str): the type of the block
'''
return self.btype
def getRaw(self):
'''
Returns the raw contents of the block, if saved to file
Outputs:
- (str): the raw contents of the block, or None
'''
return str(self.raw)
def getHeader(self, key = None, default = None):
'''
Returns the header information
Inputs:
- key (str): only returns the value of the key in the header
Outputs:
- (dict/str): either the whole header as a dict, or one value
'''
if not key is None:
if key in self.getHeader():
return self.getHeader()[key]
return default
return self.bheader
def getMetadata(self, key = None, default = None):
'''
Returns the metadata information
Inputs:
- key (str): only returns the value of the key in the metadata
Outputs:
- (dict/str): either the whole metadata as a dict, or one value
'''
if not key is None:
if key in self.getMetadata():
return self.getMetadata()[key]
return default
return self.bmetadata
def getContent(self):
'''
Returns the contents of the block
Outputs:
- (str): the contents of the block
'''
return str(self.bcontent)
def getParent(self):
'''
Returns the Block's parent Block, or None
Outputs:
- (Block): the Block's parent
'''
if type(self.parent) == str:
if self.parent == self.getHash():
self.parent = self
elif Block.exists(self.parent):
self.parent = Block(self.getMetadata('parent'), core = self.getCore())
else:
self.parent = None
return self.parent
def getDate(self):
'''
Returns the date that the block was received, if loaded from file
Outputs:
- (datetime): the date that the block was received
'''
return self.date
def getBlockFile(self):
'''
Returns the location of the block file if it is saved
Outputs:
- (str): the location of the block file, or None
'''
return self.blockFile
def isValid(self):
'''
Checks if the block is valid
Outputs:
- (bool): whether or not the block is valid
'''
return self.valid
def isSigned(self):
'''
Checks if the block was signed
Outputs:
- (bool): whether or not the block is signed
'''
return self.signed
def getSignature(self):
'''
Returns the base64-encoded signature
Outputs:
- (str): the signature, or None
'''
return self.signature
def getSignedData(self):
'''
Returns the data that was signed
Outputs:
- (str): the data that was signed, or None
'''
return self.signedData
def isSigner(self, signer, encodedData = True):
'''
Checks if the block was signed by the signer inputted
Inputs:
- signer (str): the public key of the signer to check against
- encodedData (bool): whether or not the `signer` argument is base64 encoded
Outputs:
- (bool): whether or not the signer of the block is the signer inputted
'''
try:
if (not self.isSigned()) or (not self.getCore()._utils.validatePubKey(signer)):
return False
return bool(self.getCore()._crypto.edVerify(self.getSignedData(), signer, self.getSignature(), encodedData = encodedData))
except:
return False
# setters
def setType(self, btype):
'''
Sets the type of the block
Inputs:
- btype (str): the type of block to be set to
Outputs:
- (Block): the Block instance
'''
self.btype = btype
return self
def setMetadata(self, key, val):
'''
Sets a custom metadata value
Metadata should not store block-specific data structures.
Inputs:
- key (str): the key
- val: the value (type is irrelevant)
Outputs:
- (Block): the Block instance
'''
if key == 'parent' and (not val is None) and (not val == self.getParent().getHash()):
self.setParent(val)
else:
self.bmetadata[key] = val
return self
def setContent(self, bcontent):
'''
Sets the contents of the block
Inputs:
- bcontent (str): the contents to be set to
Outputs:
- (Block): the Block instance
'''
self.bcontent = str(bcontent)
return self
def setParent(self, parent):
'''
Sets the Block's parent
Inputs:
- parent (Block/str): the Block's parent, to be stored in metadata
Outputs:
- (Block): the Block instance
'''
if type(parent) == str:
parent = Block(parent, core = self.getCore())
self.parent = parent
self.setMetadata('parent', (None if parent is None else self.getParent().getHash()))
return self
# static functions
def getBlocks(type = None, signer = None, signed = None, parent = None, reverse = False, limit = None, core = None):
'''
Returns a list of Block objects based on supplied filters
Inputs:
- type (str): filters by block type
- signer (str/list): filters by signer (one in the list has to be a signer)
- signed (bool): filters out by whether or not the block is signed
- reverse (bool): reverses the list if True
- core (Core): lets you optionally supply a core instance so one doesn't need to be started
Outputs:
- (list): a list of Block objects that match the input
'''
try:
core = (core if not core is None else onionrcore.Core())
if (not parent is None) and (not isinstance(parent, Block)):
parent = Block(hash = parent, core = core)
relevant_blocks = list()
blocks = (core.getBlockList() if type is None else core.getBlocksByType(type))
for block in blocks:
if Block.exists(block):
block = Block(block, core = core)
relevant = True
if (not signed is None) and (block.isSigned() != bool(signed)):
relevant = False
if not signer is None:
if isinstance(signer, (str,)):
signer = [signer]
if isinstance(signer, (bytes,)):
signer = [signer.decode()]
isSigner = False
for key in signer:
if block.isSigner(key):
isSigner = True
break
if not isSigner:
relevant = False
if not parent is None:
blockParent = block.getParent()
if blockParent is None:
relevant = False
else:
relevant = parent.getHash() == blockParent.getHash()
if relevant and (limit is None or len(relevant_Blocks) <= int(limit)):
relevant_blocks.append(block)
if bool(reverse):
relevant_blocks.reverse()
return relevant_blocks
except Exception as e:
logger.debug('Failed to get blocks.', error = e)
return list()
def mergeChain(child, file = None, maximumFollows = 1000, core = None):
'''
Follows a child Block to its root parent Block, merging content
Inputs:
- child (str/Block): the child Block to be followed
- file (str/file): the file to write the content to, instead of returning it
- maximumFollows (int): the maximum number of Blocks to follow
'''
# validate data and instantiate Core
core = (core if not core is None else onionrcore.Core())
maximumFollows = max(0, maximumFollows)
# type conversions
if type(child) == list:
child = child[-1]
if type(child) == str:
child = Block(child)
if (not file is None) and (type(file) == str):
file = open(file, 'ab')
# only store hashes to avoid intensive memory usage
blocks = [child.getHash()]
# generate a list of parent Blocks
while True:
# end if the maximum number of follows has been exceeded
if len(blocks) - 1 >= maximumFollows:
break
block = Block(blocks[-1], core = core).getParent()
# end if there is no parent Block
if block is None:
break
# end if the Block is pointing to a previously parsed Block
if block.getHash() in blocks:
break
# end if the block is not valid
if not block.isValid():
break
blocks.append(block.getHash())
buffer = b''
# combine block contents
for hash in blocks:
block = Block(hash, core = core)
contents = block.getContent()
contents = base64.b64decode(contents.encode())
if file is None:
try:
buffer += contents.encode()
except AttributeError:
buffer += contents
else:
file.write(contents)
if file is not None:
file.close()
return (None if not file is None else buffer)
def exists(bHash):
'''
Checks if a block is saved to file or not
Inputs:
- hash (str/Block):
- if (Block): check if this block is saved to file
- if (str): check if a block by this hash is in file
Outputs:
- (bool): whether or not the block file exists
'''
# no input data? scrap it.
if bHash is None:
return False
'''
if type(hash) == Block:
blockfile = hash.getBlockFile()
else:
blockfile = onionrcore.Core().dataDir + 'blocks/%s.dat' % hash
'''
if isinstance(bHash, Block):
bHash = bHash.getHash()
ret = isinstance(onionrstorage.getData(onionrcore.Core(), bHash), type(None))
return not ret
def getCache(hash = None):
# give a list of the hashes of the cached blocks
if hash is None:
return list(Block.blockCache.keys())
# if they inputted self or a Block, convert to hash
if type(hash) == Block:
hash = hash.getHash()
# just to make sure someone didn't put in a bool or something lol
hash = str(hash)
# if it exists, return its content
if hash in Block.getCache():
return Block.blockCache[hash]
return None
def cache(block, override = False):
# why even bother if they're giving bad data?
if not type(block) == Block:
return False
# only cache if written to file
if block.getHash() is None:
return False
# if it's already cached, what are we here for?
if block.getHash() in Block.getCache() and not override:
return False
# dump old cached blocks if the size exceeds the maximum
if sys.getsizeof(Block.blockCacheOrder) >= config.get('allocations.block_cache_total', 50000000): # 50MB default cache size
del Block.blockCache[blockCacheOrder.pop(0)]
# cache block content
Block.blockCache[block.getHash()] = block.getRaw()
Block.blockCacheOrder.append(block.getHash())
return True