''' Onionr - P2P Microblogging Platform & Social network. This class 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 . ''' import core as onionrcore, logger, config, onionrexceptions, nacl.exceptions import json, os, sys, datetime, base64 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): # take from arguments # sometimes people input a bytes object instead of str in `hash` try: hash = hash.decode() except AttributeError: pass self.hash = hash self.core = core self.btype = type self.bcontent = content # 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 # handle arguments if self.getCore() is None: self.core = onionrcore.Core() # update the blocks' contents if it exists if not self.getHash() is None: if not self.core._utils.validateHash(self.hash): logger.debug('Block hash %s is invalid.' % self.getHash()) raise onionrexceptions.InvalidHexHash('Block hash is invalid.') elif not self.update(): logger.debug('Failed to open block %s.' % self.getHash()) else: pass #logger.debug('Did not update block.') # logic def decrypt(self, anonymous=True, 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, anonymous=anonymous, encodedData=encodedData) bmeta = core._crypto.pubKeyDecrypt(self.bmetadata, anonymous=anonymous, 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, anonymous=anonymous, encodedData=encodedData) self.signer = core._crypto.pubKeyDecrypt(self.signer, anonymous=anonymous, encodedData=encodedData) self.signedData = json.dumps(self.bmetadata) + self.bcontent.decode() except nacl.exceptions.CryptoError: pass #logger.debug('Could not decrypt block. Either invalid key or corrupted data') 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: filelocation = file readfile = True if filelocation is None: if self.getHash() is None: return False elif self.getHash() in Block.getCache(): # get the block from cache, if it's in it blockdata = Block.getCache(self.getHash()) readfile = False # read from file if it's still None if blockdata is None: filelocation = 'data/blocks/%s.dat' % self.getHash() if readfile: with open(filelocation, 'rb') as f: blockdata = f.read().decode() self.blockFile = filelocation 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 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()) 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() return True except Exception as e: logger.error('Failed to update block data.', error = e, 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()) 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): with open(self.getBlockFile(), 'wb') as blockFile: blockFile.write(self.getRaw().encode()) self.update() else: self.hash = self.getCore().insertBlock(self.getContent(), header = self.getType(), sign = sign) 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 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, reverse = False, 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()) 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 relevant: 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 = 32, 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 = '' # combine block contents for hash in blocks: block = Block(hash, core = core) contents = block.getContent() contents = base64.b64decode(contents.encode()) if file is None: buffer += contents.decode() else: file.write(contents) return (None if not file is None else buffer) def createChain(data = None, chunksize = 99800, file = None, type = 'chunk', sign = True, encrypt = False, verbose = False): ''' Creates a chain of blocks to store larger amounts of data The chunksize is set to 99800 because it provides the least amount of PoW for the most amount of data. Inputs: - data (*): if `file` is None, the data to be stored in blocks - file (file/str): the filename or file object to read from (or None to read `data` instead) - chunksize (int): the number of bytes per block chunk - type (str): the type header for each of the blocks - sign (bool): whether or not to sign each block - encrypt (str): the public key to encrypt to, or False to disable encryption - verbose (bool): whether or not to return a tuple containing more info Outputs: - if `verbose`: - (tuple): - (str): the child block hash - (list): all block hashes associated with storing the file - if not `verbose`: - (str): the child block hash ''' blocks = list() # initial datatype checks if data is None and file is None: return blocks elif not (file is None or (isinstance(file, str) and os.path.exists(file))): return blocks elif isinstance(file, str): file = open(file, 'rb') if not isinstance(data, str): data = str(data) if not file is None: filesize = os.stat(file.name).st_size offset = filesize % chunksize maxtimes = int(filesize / chunksize) for times in range(0, maxtimes + 1): # read chunksize bytes from the file (end -> beginning) if times < maxtimes: file.seek(- ((times + 1) * chunksize), 2) content = file.read(chunksize) else: file.seek(0, 0) content = file.read(offset) # encode it- python is really bad at handling certain bytes that # are often present in binaries. content = base64.b64encode(content).decode() # if it is the end of the file, exit if not content: break # create block block = Block() block.setType(type) block.setContent(content) block.setParent((blocks[-1] if len(blocks) != 0 else None)) hash = block.save(sign = sign) # remember the hash in cache blocks.append(hash) elif not data is None: for content in reversed([data[n:n + chunksize] for n in range(0, len(data), chunksize)]): # encode chunk with base64 content = base64.b64encode(content.encode()).decode() # create block block = Block() block.setType(type) block.setContent(content) block.setParent((blocks[-1] if len(blocks) != 0 else None)) hash = block.save(sign = sign) # remember the hash in cache blocks.append(hash) # return different things depending on verbosity if verbose: return (blocks[-1], blocks) return blocks[-1] def exists(hash): ''' 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 hash is None: return False if type(hash) == Block: blockfile = hash.getBlockFile() else: blockfile = 'data/blocks/%s.dat' % hash return os.path.exists(blockfile) and os.path.isfile(blockfile) 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 exeeds the maximum if sys.getsizeof(Block.blockCacheOrder) >= config.get('allocations.blockCacheTotal', 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