mtg/example.config.toml

# This is an example of the configuration file for mtg. You actually can
# run mtg with it. It starts a proxy on all interfaces with a secret
# ee367a189aee18fa31c190054efd4a8e9573746f726167652e676f6f676c65617069732e636f6d
#
# It has all possible options with default values. So, a real world
# configuration file should contain only those options you are going to
# use. You do not need to enumerate all of them. In other words, each
# option here has a default value. If you comment a key-value pair, it
# should not make any effect.
#
# stats is the only exception.

# Debug starts application in debug mode. It starts to be quite verbose
# in output. Actually, the idea is that you run it in debug mode only if
# you have any issue.
debug = true

# A secret. Please remember that mtg supports only FakeTLS mode, legacy
# simple and secured mode are prohibited. For you it means that secret
# should either be base64-encoded or starts with ee.
secret = "ee367a189aee18fa31c190054efd4a8e9573746f726167652e676f6f676c65617069732e636f6d"

# Host:port pair to run proxy on.
bind-to = "0.0.0.0:3128"

# Defines how many concurrent connections are allowed to this proxy.
# All other incoming connections are going to be dropped.
concurrency = 8192

# A size of user-space buffer for TCP to use. Since we do 2 connections,
# then we have tcp-buffer * (4 + 2) per each connection: read/write for
# each connection + 2 copy buffers to pump the data between sockets.
tcp-buffer = "4kb"

# Sometimes you want to enforce mtg to use some types of
# IP connectivity to Telegram. We have 4 modes:
#   - prefer-ipv6:
#     We can use both ipv4 and ipv6 but ipv6 has a preference
#   - prefer-ipv4:
#     We can use both ipv4 and ipv6 but ipv4 has a preference
#   - only-ipv6:
#     Only ipv6 connectivity is used
#   - only-ipv4:
#     Only ipv4 connectivity is used
prefer-ip = "prefer-ipv6"

# FakeTLS uses domain fronting protection. So it needs to know a port to
# access.
domain-fronting-port = 443

# FakeTLS can compare timestamps to prevent probes. Each message has
# encrypted timestamp. So, mtg can compare this timestamp and decide if
# we need to proceed with connection or not.
#
# Sometimes time can be skewed so we accept all messages within a
# time range of this parameter.
tolerate-time-skewness = "5s"

# Telegram has a concept of DC. You can think about DC as a number of a cluster
# with a certain purpose. Some clusters serve media, some - messages, some rule
# channels and so on. But sometimes unknown DC number is requested by client.
# It could be a bug or some global reconfiguration of the Telegram.
#
# By default, proxy rejects such requests. But it is also possible to fallback
# this request to any DC. Telegram works in a way that any DC is able to serve
# any request but sacrificing a latency.
#
# If this setting is disabled (default), mtg will reject a connection.
# Otherwise, chose a new DC.
allow-fallback-on-unknown-dc = false

# network defines different network-related settings
[network]
# please be aware that mtg needs to do some external requests. For
# example, if you do not pass public ips, it will request your public ip
# address from some external service.
#
# As for 2.0, if you set a public-ip on your own, mtg won't issue any
# network requests except of those required for Telegram.
#
# so, in order of doing them, it needs to do DNS lookup. mtg ignores DNS
# resolver of the operating system and uses DOH instead. This is a host
# it has to access.
#
# By default we use Quad9.
doh-ip = "9.9.9.9"

# mtg can work via proxies (for now, we support only socks5). Proxy
# configuration is done via list. So, you can specify many proxies
# there.
#
# Actually, if you supply an empty list, then no proxies are going to be
# used. If you supply a single proxy, then mtg will use it exclusively.
# If you supply >= 2, then mtg will load balance between them.
#
# If you add an empty string here, this is an equivalent of 'plain network',
# with no proxy usage.
#
# Proxy configuration is done via ordinary URI schema:
#
#     socks5://user:password@host:port?open_threshold=5&half_open_timeout=1m&reset_failures_timeout=10s
#
# Only socks5 proxy is used. user/password is optional. As you can
# see, you can specify some parameters in GET query. These parameters
# configure circuit breaker.
#
# open_threshold means a number of errors which should happen so we stop
# use a proxy.
#
# half_open_timeout means a time period (in Golang duration notation)
# after which we can retry with this proxy
#
# reset_failures_timeout means a time period when we flush out errors
# when circuit breaker in closed state.
#
# Please see https://docs.microsoft.com/en-us/azure/architecture/patterns/circuit-breaker
# on details about circuit breakers.
proxies = [
    # "socks5://user:password@host:port?open_threshold=5&half_open_timeout=1m&reset_failures_timeout=10s"
]

# network timeouts define different settings for timeouts. tcp timeout
# define a global timeout on establishing of network connections. idle
# means a timeout on pumping data between sockset when nothing is
# happening.
#
# please be noticed that handshakes have no timeouts intentionally. You can
# find a reasoning here:
# https://www.ndss-symposium.org/wp-content/uploads/2020/02/23087-paper.pdf
[network.timeout]
tcp = "5s"
http = "10s"
idle = "1m"

# Some countries do active probing on Telegram connections. This technique
# allows to protect from such effort.
#
# mtg has a cache of some connection fingerprints. Actually, first bytes
# of each connection. So, it stores them in some in-memory LRU+TTL cache.
# You can configure this cache here.
[defense.anti-replay]
# You can enable/disable this feature.
enabled = true
# max size of such a cache. Please be aware that this number is
# approximate we try hard to store data quite dense but it is possible
# that we can go over this limit for 10-20% under some conditions and
# architectures.
max-size = "1mib"
# we use stable bloom filters for anti-replay cache. This helps
# to maintain a desired error ratio.
error-rate = 0.001

# You can protect proxies by using different blocklists. If client has
# ip from the given range, we do not try to do a proper handshake. We
# actually route it to fronting domain. So, this client will never ever
# have a chance to use mtg to access Telegram.
#
# Please remember that blocklists are initialized in async way. So,
# when you start a proxy, blocklists are empty, they are populated and
# processed in backgrounds. An error in any URL is ignored.
[defense.blocklist]
# You can enable/disable this feature.
enabled = true
# This is a limiter for concurrency. In order to protect website
# from overloading, we download files in this number of threads.
download-concurrency = 2
# A list of URLs in FireHOL format (https://iplists.firehol.org/)
# You can provider links here (starts with https:// or http://) or
# path to a local file, but in this case it should be absolute.
urls = [
    # "https://iplists.firehol.org/files/firehol_level1.netset",
    # "/local.file"
]
# How often do we need to update a blocklist set.
update-each = "24h"

# statsd statistics integration.
[stats.statsd]
# enabled/disabled
enabled = false
# host:port for UDP endpoint of statsd
address = "127.0.0.1:8888"
# prefix of metric for statsd
metric-prefix = "mtg"
# tag format to use
# supported values are 'datadog', 'influxdb' and 'graphite'
# default format is graphite.
tag-format = "datadog"

# prometheus metrics integration.
[stats.prometheus]
# enabled/disabled
enabled = true
# host:port where to start http server for endpoint
bind-to = "127.0.0.1:3129"
# prefix of http path
http-path = "/"
# prefix for metrics for prometheus
metric-prefix = "mtg"