johndoe31415/ratchedRatched é um proxy TLS transparente Man-in-the-Middle destinado a testes de penetração.
ratched é um proxy Man-in-the-Middle (MitM) que intercepta especificamente conexões TLS. Destina-se a ser usado em conjunto com o alvo REDIRECT do iptables do Linux; todas as conexões que devem ser interceptadas podem ser redirecionadas para a porta local do ratched. Através do sockopt SO_ORIGINAL_DST, o ratched pode determinar o destino pretendido (antes da manipulação de pacotes do iptables) e tenta estabelecer uma conexão com o destino original.
O que o diferencia de outros softwares MitM é o seguinte:
O ratched não intercepta tráfego indiscriminadamente. Em particular, ele primeiro aguarda o cliente TLS enviar seu ClientHello para que o ratched possa analisá-lo e decidir pela extensão TLS Server Name Indication (SNI) se o destino deve ser interceptado ou não. Isso é particularmente útil quando você tem hospedagem virtual, mas só deseja interceptar conexões para um hostname específico.
O ratched não se destina apenas a capturar senhas, mas principalmente a despejar o tráfego em um arquivo PCAPNG. O formato de arquivo PCAPNG foi escolhido porque permite a anotação de conexões com comentários (em particular, qual hostname foi indicado na extensão SNI) e também permite que informações de resolução de nomes sejam incorporadas no arquivo de captura (novamente, para mapear o endereço IP de destino para o hostname da extensão SNI)
O ratched tem configuração individual para cada SNI interceptado, incluindo grupos suportados (anteriormente conhecidos como "curvas elípticas suportadas"), conjuntos de cifras e versões TLS específicas no lado do cliente e servidor, e permite especificar certificados/chaves personalizados para diferentes hosts interceptados.
O ratched fornece suporte extensivo para certificados de cliente e também oferece forjamento automático para certificados de cliente (semelhante a certificados de servidor forjados na outra direção).
O ratched suporta OCSP stapling e pode forjar automaticamente respostas OCSP positivas quando um cliente envia uma extensão TLS de solicitação de status.
Uma vez que o ratched esteja ouvindo na máquina de roteamento (no exemplo, na porta 9999), basta adicionar uma entrada no iptables que especifique qual tráfego você deseja capturar. Por exemplo, para interceptar tudo de 192.168.1.7 que tenta alcançar a porta 443, use:
# iptables -t nat -A PREROUTING -p tcp -s 192.168.1.7 --dport 443 -j REDIRECT --to-ports 9999
Para interceptar tudo que vai para a porta 443, simplesmente faça:
# iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-ports 9999
Se você está atuando como roteador e deseja interceptar tráfego local de entrada, use o alvo DNAT em vez de REDIRECT, como:
# iptables -t nat -A PREROUTING -i eth1 -p tcp --dport 443 -j DNAT --to 192.168.123.1:9999
Aqui, eth1 é a interface onde você está interceptando o tráfego e 192.168.123.1 é o endereço IP da interface local.
A página de ajuda deve ser bastante autoexplicativa:
usage: ratched [-c path] [-f hostname:port] [--single-shot] [--dump-certs]
[--keyspec keyspec] [--initial-read-timeout secs]
[--mark-forged-certificates] [--no-recalculate-keyids]
[--daemonize] [--logfile file] [--flush-logs] [--crl-uri uri]
[--ocsp-uri uri] [--write-memdumps-into-files]
[--use-ipv6-encapsulation] [-l hostname:port]
[-d key=value[,key=value,...]] [-i hostname[,key=value,...]]
[--pcap-comment comment] [-o filename] [-v]
ratched - TLS connection router that performs a man-in-the-middle attack
optional arguments:
-c path, --config-dir path
Configuration directory where the default root CA
certificate, CA keypair and server keypair are stored.
Defaults to ~/.config/ratched
-f hostname:port, --local-fwd hostname:port
When local connection to listening port is made, the
connection is discarded by default. Specifying this
option makes ratched forward to the given
hostname/port combination instead. Useful for testing
the proxy without the iptables REDIRECT.
--single-shot Only handle a single connection and terminate directly
after. Useful for debugging purposes.
--dump-certs Print created certificates for each intercepted
connection in the log file. Note that in many cases
you will also need to increase the log level to at
least DEBUG in order to see certificates.
--keyspec keyspec Specification for the private keys that should be
used. Can be either in the form "rsa:bitlen" or
"ecc:curvename". Valid choices, therefore, would be,
for example, "rsa:1024" or "ecc:secp256r1". Defaults
to rsa:2048
--initial-read-timeout secs
Specifies the amount of time in seconds (as a floating
point number) that ratched waits for the client to
provide its ClientHello before giving up. The default
is 1.0 secs.
--mark-forged-certificates
Include an OU=ratched entry to the subjects of all
created certificates (including dynamically forged
client certificates) for easy debugging.
--no-recalculate-keyids
When forging client certificates, by default the
subject and authority key identifiers are removed and
recreated to fit the actually used key ids. With this
option, they're used as-is (i.e., the key identifier
metadata will not fit the actually used keys). This
option might expose bugs in certain frameworks which
regard these identifiers as trusted information.
--daemonize Do not run in foreground mode, but in the background
as a daemon.
--logfile file Instead of logging to stderr, redirect logs to given
file.
--flush-logs Flush logfile after each call to logmsg(). Decreases
performance, but gives line-buffered logs.
--crl-uri uri Encode the given URI into the CRL Distribution Point
X.509 extension of server certificates.
--ocsp-uri uri Encode the given URI into the Authority Info Access
X.509 extension of server certificates as the OCSP
responder URI.
--write-memdumps-into-files
When dumping a piece of memory in the log, also output
its binary equivalent into a file called
hexdump_####.bin, where #### is an ascending number.
Useful for debugging of internal data structures.
--use-ipv6-encapsulation
For writing the PCAPNG file format, usually IPv4 is
emulated. This has the drawback that when one IPv4
endpoint serves multiple servers via the TLS Server
Name Indication extension, they cannot be
differentiated by their hostname. With this parameter,
ratched wraps the packets in IPv4-in-IPv6 emulation
and assigns different IPv6 addresses for different
server names, thus enabling accurate name resolution.
-l hostname:port, --listen hostname:port
Specify the address and port that ratched is listening
on. Defaults to 127.0.0.1:9999.
-d key=value[,key=value,...], --defaults key=value[,key=value,...]
Specify the server and client connection parameters
for all hosts that are not explicitly listed via a
--intercept option. Arguments are given in a key=value
fashion; valid arguments are shown below.
-i hostname[,key=value,...], --intercept hostname[,key=value,...]
Intercept only a specific host name, as indicated by
the Server Name Indication inside the ClientHello. Can
be specified multiple times to include interception or
more than one host. Additional arguments can be
specified in a key=value fashion to further define
interception parameters for that particular host.
--pcap-comment comment
Store a particular piece of information inside the
PCAPNG header as a comment.
-o filename, --outfile filename
Specifies the PCAPNG file that the intercepted traffic
is written to. Mandatory argument.
-v, --verbose Increase logging verbosity.
The arguments which are valid for the --intercept argument are as follows:
intercept=[opportunistic|mandatory|forward|reject]
Specifies the mode that ratched should act in for
this particular connection. Opportunistic TLS
interception is the default; it means that TLS
interception is tried first. Should it fail, however
(because someone tries to send non-TLS traffic), it
falls back to 'forward' mode (i.e., forwarding all
data unmodified). Mandatory TLS interception means
that if no TLS interception is possible, the
connection is terminated. 'forward', as explained,
simply forwards everything unmodified. 'reject'
closes the connection altogether, regardless of the
type of seen traffic.
s_tlsversions=versions
Colon-separated string that specifies the acceptable
TLS version for the ratched server component. Valid
elements are ssl2, ssl3, tls10, tls11, tls12, tls13.
Defaults to tls10:tls11:tls12.
s_reqclientcert=bool Ask all connecting clients to the server side of the
TLS proxy for a client certificate. If not
replacement certificate (at least certfile and
keyfile) is given, forge all metadata of the incoming
certificate. If a certfile/keyfile is given, this
option is implied.
s_send_rot=bool By default, the ratched TLS server does not include
its own root of trust (RoT) CA certificate in the
server certificates list. With this option, it is
added to the certificates sent to its peer.
s_certfile=filename Specifies an X.509 certificate in PEM format that
should be used by ratched as the server certificate.
By default, this certificate is automatically
generated. Must be used in conjunction with
s_keyfile.
s_keyfile=filename Specifies the private key for the given server
certificate, in PEM format.
s_chainfile=filename Specifies the X.509 certificate chain that is to be
sent to the client, in PEM format.
s_cacert=filename The X.509 CA certificate that issues server
certificates, in PEM format.
s_cakey=filename The X.509 CA certificate key that signs server
certificates, in PEM format.
s_ciphers=ciphers The cipher suite string that the ratched TLS server
uses.
s_groups=groups The key agreement 'supported groups' string (formerly
known as 'elliptic curves') that the ratched TLS
server uses.
s_sigalgs=algs The key agreement 'signature algorithms' string which
the ratched TLS server uses.
s_ocsp=bool Respond to clients requesting an OCSP status request
by sending an OCSP ticket as a response. Enabled by
default.
c_tlsversions=versions
Colon-separated string that specifies the acceptable
TLS version for the ratched client component. Valid
elements are ssl2, ssl3, tls10, tls11, tls12, tls13.
Defaults to tls10:tls11:tls12.
c_certfile=filename Specifies an X.509 certificate in PEM format that
should be used by ratched as a client certificate. It
will only be used when the connecting client also
provided a client certificate. Must be used in
conjunction with c_keyfile.
c_keyfile=filename The private key for the given client certificate, in
PEM format.
c_chainfile=filename The X.509 certificate chain that is to be sent to the
server, in PEM format.
c_ciphers=ciphers The cipher suite string that the ratched TLS client
uses.
c_groups=groups The key agreement 'supported groups' string (formerly
known as 'elliptic curves') that the ratched TLS
client uses.
c_sigalgs=algs The key agreement 'signature algorithms' string which
the ratched TLS client uses.
examples:
$ ratched -o output.pcapng
Open up local port 9999 and listen for incoming connections, intercept
all TLS traffic and write output into given capture file.
$ ratched -f google.com:443 -o output.pcapng
Same as before, but redirect all traffic of which the destination cannot
be determined (e.g., local connections to port 9999) to google.com on
port 443.
$ ratched -vvv --dump-certs -o output.pcapng
Be much more verbose during interception and also print out forged
certificates in the log.
$ ratched --defaults intercept=forward -intercept --intercept www.johannes-bauer.com -o output.pcapng
Do not generally intercept connections (but rather forward all traffic
unmodified) except for connections with Server Name Indication
www.johannes-bauer.com, on which interception is performed.
$ ratched --intercept www.johannes-bauer.com,s_reqclientcert=true -o output.pcapng
Generally do not request client certificates from connecting peers
except for connections with Server Name Indication www.johannes-
bauer.com, where clients are sent a CertificateRequest TLS message. If
clients do not provide a client certificate, just use regular TLS
interception. If they do provide a client certificate, forge all client
certificate metadata and use the forged client certificate in the
connection against the real server.
$ ratched --intercept www.johannes-bauer.com,c_certfile=joe.crt,c_keyfile=joe.key -o output.pcapng
Same as before, but for connections to johannes-bauer.com, do not forge
client certificates, but always use the given client certificate and key
(joe.crt / joe.key) for authentication against the server.
$ ratched --keyspec ecc:secp256r1 --ocsp-uri http://www.ocsp-server.com -o output.pcapng
Choose secp256r1 instead of RSA-2048 for all used certificates and
encode an OCSP Responder URI into those forged certificates as well.
$ ratched --initial-read-timeout 5.0 --default intercept=mandatory -o output.pcapng
Wait five seconds for connecting clients to send a valid ClientHello
message. If after five seconds nothing is received or if unknown (non-
TLS) traffic is received, terminate the connection instead of performing
unmodified forwarding.
O nome "ratched" alude à enfermeira Ratched de "Um Estranho no Ninho". Se você usar a ferramenta para espionar pessoas, você é um completo idiota e está abusando do seu poder. Você deveria assistir ao filme. Por favor, use o ratched de forma responsável para aumentar a segurança da nossa infraestrutura, não para prejudicá-la. A interceptação TLS para fins de espionagem é desprezível e perigosa.
O ratched requer pelo menos OpenSSL v1.1.
O ratched é licenciado sob a GNU GPL-3.