t opicos em seguranca˘ da informa˘c~ao aula 4sendin/cursos/tseg/2s2019/aula4.pdf · tseg-4 ivan...
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TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Topicos em Seguranca da Informacao
Aula 4
Ivan Sendin
FACOM - Universidade Federal de Uberlandiaivansendin@yahoo.com,sendin@ufu.br
6 de setembro de 2019
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Aula passada - RSA
Forca bruta
2 ou 3 finalizacoes
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
def expMod(b,e,m):
if e==0:
return 1
if e==1:
return b
if (e%2)==0:
temp = expMod(b,e/2,m)
#print temp*temp
return temp*temp % m
#else
temp = expMod(b,e/2,m)
#print temp*temp*b
return temp*temp*b % m
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Aula passada - RSA
Forca bruta
2 ou 3 finalizacoes
Exponenciacao Modular... deve aumentar,curiosidade.
Fatorar e exponencial: PK + n fatorado == SK
(Curvas Elipticas)
Aniversario: grande diferenca do ingenuo. As PKssao hashes/numeros aleatorios
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Bitcoin’s academic pedigree
Bitcoin foi ”iventado”pelo Satoshi Nakamoto
Sera? Como?
Bitcoin’s academic pedigree Narayanan, ArvindClark, Jeremy.
Timestamping/log seguros: merkle Tree,encadeamento (Haber/Stornetta)
Digital Cash: sempre esbarravamna centralizacao
PoW: compromisso com o sistema. HashCash
Tolerancia a Falhas: Generais Bizantinos
PK como identidades
Smart Contracts: Szabo
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Bitcoin’s academic pedigree
Minhas insercoes
Filtros De Bloom
Merkle Patricia Trie
DHT
Assinaturas Anonimas
Zero-knowledge proof
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Binarios...
bitcoin.org
BitCoin Core
Linux, Windows, Mac OS X, ARM
Open Source/MIT
TCP 8333
Deamon/binarios utilitarios
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Binarios...
Ao iniciar o binario vai conectar na rede P2P
seed.bitcoin.sipa.be,dnsseed.bluematt.me,dnsseed.bitcoin.dashjr.org, seed.bitcoinstats.com,seed.bitcoin.jonasschnelli.ch, seed.btc.petertodd.org
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
darth@kali:/TSeg/2S2019/aulas$ nslookup seed.bitcoin.sipa.be
Server: 179.155.64.31
Address: 179.155.64.31#53
Non-authoritative answer:
Name: seed.bitcoin.sipa.be
Address: 176.254.67.102
Name: seed.bitcoin.sipa.be
Address: 172.105.112.233
Name: seed.bitcoin.sipa.be
Address: 88.130.223.19
Name: seed.bitcoin.sipa.be
Address: 45.48.177.222
Name: seed.bitcoin.sipa.be
Address: 82.74.205.180
Name: seed.bitcoin.sipa.be
Address: 52.52.77.168
...
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Binarios...
O binario ira conectar em algum(ns) dos enderecos
e solicitar mais enderecos
Padrao 125 conexoes (8+117)
Simplified Payment Verification - SPV
Full Node
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Binarios...
Uma vez conectado, o bitcoin iniciara o downloadda blockchain
”Pede”aos pares pelos blocos
Os blocos sao salvosLevelDB : key/valueblk*.dat / rev*.dat
Ate sincronizar...
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Binarios...
Recebe transacoes
Validar as transacoes
assinaturasUTXO
Propagar as transacoes
Receber, validar e propagar novos blocos
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Binarios...
Rodando um no, voce pode consultar a blockchain
interferir nos novos blocos, enviando uma transacoes
binarios ou RPC
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Binarios...
Carteiras Exportar, backup, cifrar, saldo/balanco,...
Rede getpeerinfo, addnode,....
Bloco Consultas diversas
Transacoes Criar transacoes (e.g. multisig, timelock,...)
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Exchanges
Nao e necessario instalar o Bitcoin Core para possuirBitcoins
As ”Exchanges”facilitam as coisas
Funcionam como bancos
Escondem as complexidades do bitcoin do usuariocomum
Interface bitcoin/mundo real
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Exchanges
Cadastro: “Know Your Client (KYC)”, passaporte,motorista, endereA§o, CPF,...
A exchange controla a suas SKs (login)
Provimento de fundos: transferencia bancaria, CC
Compra e venda de criptomoedas (trading)
Recebimento e envio de BTC (e outras)
Saque em moeda fiat
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Exchanges
Compra e venda de criptomoedas nao alteram ablockchain
Taxa ¡1%(?)
A Exchange possui um montante e voce compra evende deste montante
Equivalente a invetimento em ouro
Recebimento e envios sA£o diferentes
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Exchanges
Prova de solvencia (teorica)
Auditoria
Muitos, muitos casos deroubos/estelionato/sequestro
https://edition.cnn.com/2019/02/05/tech/
quadriga-gerald-cotten-cryptocurrency/
index.html
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Blockexplorer
Sao servicos de analise de Blockchain
Resolvem, por exemplo a indirecao do blockcain(blocos e transacoes)
API de acesso
walletexplorer, opreturn
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Blockexplorer
https://www.blockchain.com/explorer
Varias criptomoedas, arafo de transacoes,API/JSON, mineracao servico de carteira
https://blockexplorer.com/,https://live.blockcypher.com/btc/,https://chain.so/
https://etherscan.io/,https://www.etherchain.org/
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Blockexplorer
https://www.walletexplorer.com
Organiza as carteiras: exchanges, Pools, Aposta eServicos. https://www.chainalysis.com/
https://opreturn.org/ ehttps://opreturn.net/
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Altcoins
No rastro do bitcoin, foram criadas inumeras(centenas) de criptomoedas
Marketing/Nicho/governo, stable, anonimato,alternativas ao PoW, recursos,...
EOS,Ethereum,Lite, ripple, zcash
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Ethereum
Vitalik Buterin
Pioneiro do Bitcoin
Proof of Stake
Smart Contract
DAO - decentralized autonomous organization
Problemas recorrentes de seguranca em diversosnıveis....
Jogos e apostas....
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Litecoin
Muito parecida com o bitcoin
Espaco razoavel no mercado
(Numero de moedas X Cotacao)
Mecanismo de consenso: gastamemoria...(GPU/ASIC)
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Outras
Ripple: envio de valores globalmente. Itau,Santander,...
(Algum gradu) Anonimas: Zcash, Monero,...
TSEG-4
Ivan Sendin
Aula Passada
Bicoin Pedigree
Bitcoin
Pedegree
Exchanges
Blockexplorers
Altcoins
Exercicios
Pioneiros
Os pioneiros do Bitcoin devem ser bilionarios?!?
Usando um blockexplorer:
Verificar as carteiras que receberam os primeirosbitcoins mineradosApresentar um resumo financeiro
Atencao para o limite de consulta do site!!
Da para comecar AGORA!!!Nao sai da sala comduvidas!
Entrega: 13/Set (PDF do codigo e resultados)
Valor= 5
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