ooni-probe-cli/internal/cmd/jafar/iptables/iptables_linux.go
Simone Basso 6924d1ad81
refactor: only use shaping dialer for ndt7 and dash (#754)
See https://github.com/ooni/probe/issues/2112 for context.

While there, run `go fix -fix buildtag ./...`
2022-05-24 18:23:42 +02:00

120 lines
4.4 KiB
Go

//go:build linux
package iptables
import (
"github.com/apex/log"
"github.com/ooni/probe-cli/v3/internal/runtimex"
"github.com/ooni/probe-cli/v3/internal/shellx"
)
type linuxShell struct{}
func (s *linuxShell) createChains() (err error) {
defer func() {
if recover() != nil {
// JUST KNOW WE'VE BEEN HERE
}
}()
err = shellx.Run(log.Log, "sudo", "iptables", "-N", "JAFAR_INPUT")
runtimex.PanicOnError(err, "cannot create JAFAR_INPUT chain")
err = shellx.Run(log.Log, "sudo", "iptables", "-N", "JAFAR_OUTPUT")
runtimex.PanicOnError(err, "cannot create JAFAR_OUTPUT chain")
err = shellx.Run(log.Log, "sudo", "iptables", "-t", "nat", "-N", "JAFAR_NAT_OUTPUT")
runtimex.PanicOnError(err, "cannot create JAFAR_NAT_OUTPUT chain")
err = shellx.Run(log.Log, "sudo", "iptables", "-I", "OUTPUT", "-j", "JAFAR_OUTPUT")
runtimex.PanicOnError(err, "cannot insert jump to JAFAR_OUTPUT")
err = shellx.Run(log.Log, "sudo", "iptables", "-I", "INPUT", "-j", "JAFAR_INPUT")
runtimex.PanicOnError(err, "cannot insert jump to JAFAR_INPUT")
err = shellx.Run(log.Log, "sudo", "iptables", "-t", "nat", "-I", "OUTPUT", "-j", "JAFAR_NAT_OUTPUT")
runtimex.PanicOnError(err, "cannot insert jump to JAFAR_NAT_OUTPUT")
return nil
}
func (s *linuxShell) dropIfDestinationEquals(ip string) error {
return shellx.Run(log.Log,
"sudo", "iptables", "-A", "JAFAR_OUTPUT", "-d", ip, "-j", "DROP")
}
func (s *linuxShell) rstIfDestinationEqualsAndIsTCP(ip string) error {
return shellx.Run(log.Log,
"sudo", "iptables", "-A", "JAFAR_OUTPUT", "--proto", "tcp", "-d", ip,
"-j", "REJECT", "--reject-with", "tcp-reset",
)
}
func (s *linuxShell) dropIfContainsKeywordHex(keyword string) error {
return shellx.Run(log.Log,
"sudo", "iptables", "-A", "JAFAR_OUTPUT", "-m", "string", "--algo", "kmp",
"--hex-string", keyword, "-j", "DROP",
)
}
func (s *linuxShell) dropIfContainsKeyword(keyword string) error {
return shellx.Run(log.Log,
"sudo", "iptables", "-A", "JAFAR_OUTPUT", "-m", "string", "--algo", "kmp",
"--string", keyword, "-j", "DROP",
)
}
func (s *linuxShell) rstIfContainsKeywordHexAndIsTCP(keyword string) error {
return shellx.Run(log.Log,
"sudo", "iptables", "-A", "JAFAR_OUTPUT", "-m", "string", "--proto", "tcp", "--algo",
"kmp", "--hex-string", keyword, "-j", "REJECT", "--reject-with", "tcp-reset",
)
}
func (s *linuxShell) rstIfContainsKeywordAndIsTCP(keyword string) error {
return shellx.Run(log.Log,
"sudo", "iptables", "-A", "JAFAR_OUTPUT", "-m", "string", "--proto", "tcp", "--algo",
"kmp", "--string", keyword, "-j", "REJECT", "--reject-with", "tcp-reset",
)
}
func (s *linuxShell) hijackDNS(address string) error {
// Hijack any DNS query, like the Vodafone station does when using the
// secure network feature. Our transparent proxies will use DoT, in order
// to bypass this restriction and avoid routing loop.
return shellx.Run(log.Log,
"sudo", "iptables", "-t", "nat", "-A", "JAFAR_NAT_OUTPUT", "-p", "udp",
"--dport", "53", "-j", "DNAT", "--to", address,
)
}
func (s *linuxShell) hijackHTTPS(address string) error {
// We need to whitelist root otherwise the traffic sent by Jafar
// itself will match the rule and loop.
return shellx.Run(log.Log,
"sudo", "iptables", "-t", "nat", "-A", "JAFAR_NAT_OUTPUT", "-p", "tcp",
"--dport", "443", "-m", "owner", "!", "--uid-owner", "0",
"-j", "DNAT", "--to", address,
)
}
func (s *linuxShell) hijackHTTP(address string) error {
// We need to whitelist root otherwise the traffic sent by Jafar
// itself will match the rule and loop.
return shellx.Run(log.Log,
"sudo", "iptables", "-t", "nat", "-A", "JAFAR_NAT_OUTPUT", "-p", "tcp",
"--dport", "80", "-m", "owner", "!", "--uid-owner", "0",
"-j", "DNAT", "--to", address,
)
}
func (s *linuxShell) waive() error {
shellx.RunQuiet("sudo", "iptables", "-D", "OUTPUT", "-j", "JAFAR_OUTPUT")
shellx.RunQuiet("sudo", "iptables", "-D", "INPUT", "-j", "JAFAR_INPUT")
shellx.RunQuiet("sudo", "iptables", "-t", "nat", "-D", "OUTPUT", "-j", "JAFAR_NAT_OUTPUT")
shellx.RunQuiet("sudo", "iptables", "-F", "JAFAR_INPUT")
shellx.RunQuiet("sudo", "iptables", "-X", "JAFAR_INPUT")
shellx.RunQuiet("sudo", "iptables", "-F", "JAFAR_OUTPUT")
shellx.RunQuiet("sudo", "iptables", "-X", "JAFAR_OUTPUT")
shellx.RunQuiet("sudo", "iptables", "-t", "nat", "-F", "JAFAR_NAT_OUTPUT")
shellx.RunQuiet("sudo", "iptables", "-t", "nat", "-X", "JAFAR_NAT_OUTPUT")
return nil
}
func newShell() *linuxShell {
return &linuxShell{}
}