Update docs

This commit is contained in:
9seconds
2022-08-04 18:39:00 +03:00
parent 008e17cdff
commit 6a19ded78e
26 changed files with 319 additions and 344 deletions
+17 -17
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@@ -29,13 +29,13 @@ type EventStart struct {
RemoteIP net.IP
}
// EventConnectedToDC is emitted when mtg proxy has connected to a
// Telegram server.
// EventConnectedToDC is emitted when mtg proxy has connected to a Telegram
// server.
type EventConnectedToDC struct {
eventBase
// RemoteIP is an IP address of the Telegram server proxy has been
// connected to.
// RemoteIP is an IP address of the Telegram server proxy has been connected
// to.
RemoteIP net.IP
// DC is an index of the datacenter proxy has been connected to.
@@ -49,15 +49,15 @@ type EventTraffic struct {
// Traffic is a count of bytes which were transmitted.
Traffic uint
// IsRead defines if we _read_ or _write_ to connection. A rule of
// thumb is simple: EventTraffic is bound to a remote connection. Not
// to a client one, but either to Telegram or front domain one.
// IsRead defines if we _read_ or _write_ to connection. A rule of thumb is
// simple: EventTraffic is bound to a remote connection. Not to a client one,
// but either to Telegram or front domain one.
//
// In the case of Telegram, isRead means that we've fetched some bytes
// from Telegram to send it to a client.
// In the case of Telegram, isRead means that we've fetched some bytes from
// Telegram to send it to a client.
//
// In the case of the front domain, it means that we've fetched some
// bytes from this domain to send it to a client.
// In the case of the front domain, it means that we've fetched some bytes
// from this domain to send it to a client.
IsRead bool
}
@@ -66,20 +66,20 @@ type EventFinish struct {
eventBase
}
// EventDomainFronting is emitted when we connect to a front domain
// instead of Telegram server.
// EventDomainFronting is emitted when we connect to a front domain instead of
// Telegram server.
type EventDomainFronting struct {
eventBase
}
// EventConcurrencyLimited is emitted when connection was declined
// because of the concurrency limit of the worker pool.
// EventConcurrencyLimited is emitted when connection was declined because of
// the concurrency limit of the worker pool.
type EventConcurrencyLimited struct {
eventBase
}
// EventIPBlocklisted is emitted when connection was declined because
// IP address was found in IP blocklist.
// EventIPBlocklisted is emitted when connection was declined because IP
// address was found in IP blocklist.
type EventIPBlocklisted struct {
eventBase
+124 -139
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@@ -1,20 +1,19 @@
// mtglib defines a package with MTPROTO proxy.
//
// Since mtg itself is build as an example of how to work with mtglib,
// it worth to telling a couple of words about a project organization.
// Since mtg itself is build as an example of how to work with mtglib, it worth
// to telling a couple of words about a project organization.
//
// A core object of the project is mtglib.Proxy. This is a proxy you
// expect: that one which you configure, set to serve on a listener
// and/or shutdown on application termination.
// A core object of the project is [mtglib.Proxy]. This is a proxy you expect:
// that one which you configure, set to serve on a listener and/or shutdown on
// application termination.
//
// But it also has a core logic unrelated to Telegram per se: anti
// replay cache, network connectivity (who knows, maybe you want to have
// a native VMESS integration) and so on.
// But it also has a core logic unrelated to Telegram per se: anti replay
// cache, network connectivity (who knows, maybe you want to have a native
// VMESS integration) and so on.
//
// You can supply such parts to a proxy with interfaces. The rest of
// the packages in mtg define some default implementations of these
// interfaces. But if you want to integrate it with, let say, influxdb,
// you can do it easily.
// You can supply such parts to a proxy with interfaces. The rest of the
// packages in mtg define some default implementations of these interfaces. But
// if you want to integrate it with, let say, influxdb, you can do it easily.
package mtglib
import (
@@ -28,42 +27,42 @@ import (
)
var (
// ErrSecretEmpty is returned if you are trying to create a proxy
// but do not provide a secret.
// ErrSecretEmpty is returned if you are trying to create a proxy but do not
// provide a secret.
ErrSecretEmpty = errors.New("secret is empty")
// ErrSecretInvalid is returned if you are trying to create a proxy
// but secret value is invalid (no host or payload are zeroes).
// ErrSecretInvalid is returned if you are trying to create a proxy but secret
// value is invalid (no host or payload are zeroes).
ErrSecretInvalid = errors.New("secret is invalid")
// ErrNetworkIsNotDefined is returned if you are trying to create a
// proxy but network value is undefined.
// ErrNetworkIsNotDefined is returned if you are trying to create a proxy but
// network value is undefined.
ErrNetworkIsNotDefined = errors.New("network is not defined")
// ErrAntiReplayCacheIsNotDefined is returned if you are trying to
// create a proxy but anti replay cache value is undefined.
// ErrAntiReplayCacheIsNotDefined is returned if you are trying to create a
// proxy but anti replay cache value is undefined.
ErrAntiReplayCacheIsNotDefined = errors.New("anti-replay cache is not defined")
// ErrIPBlocklistIsNotDefined is returned if you are trying to
// create a proxy but ip blocklist instance is not defined.
// ErrIPBlocklistIsNotDefined is returned if you are trying to create a proxy
// but ip blocklist instance is not defined.
ErrIPBlocklistIsNotDefined = errors.New("ip blocklist is not defined")
// ErrIPAllowlistIsNotDefined is returned if you are trying to
// create a proxy but ip allowlist instance is not defined.
// ErrIPAllowlistIsNotDefined is returned if you are trying to create a proxy
// but ip allowlist instance is not defined.
ErrIPAllowlistIsNotDefined = errors.New("ip allowlist is not defined")
// ErrEventStreamIsNotDefined is returned if you are trying to create a
// proxy but event stream instance is not defined.
// ErrEventStreamIsNotDefined is returned if you are trying to create a proxy
// but event stream instance is not defined.
ErrEventStreamIsNotDefined = errors.New("event stream is not defined")
// ErrLoggerIsNotDefined is returned if you are trying to
// create a proxy but logger is not defined.
// ErrLoggerIsNotDefined is returned if you are trying to create a proxy but
// logger is not defined.
ErrLoggerIsNotDefined = errors.New("logger is not defined")
)
const (
// DefaultConcurrency is a default max count of simultaneously
// connected clients.
// DefaultConcurrency is a default max count of simultaneously connected
// clients.
DefaultConcurrency = 4096
// DefaultBufferSize is a default size of a copy buffer.
@@ -71,31 +70,29 @@ const (
// Deprecated: this setting no longer makes any effect.
DefaultBufferSize = 16 * 1024 // 16 kib
// DefaultDomainFrontingPort is a default port (HTTPS) to connect to in
// case of probe-resistance activity.
// DefaultDomainFrontingPort is a default port (HTTPS) to connect to in case
// of probe-resistance activity.
DefaultDomainFrontingPort = 443
// DefaultIdleTimeout is a default timeout for closing a connection
// in case of idling.
// DefaultIdleTimeout is a default timeout for closing a connection in case of
// idling.
//
// Deprecated: no longer in use because of changed TCP relay
// algorithm.
// Deprecated: no longer in use because of changed TCP relay algorithm.
DefaultIdleTimeout = time.Minute
// DefaultTolerateTimeSkewness is a default timeout for time
// skewness on a faketls timeout verification.
// DefaultTolerateTimeSkewness is a default timeout for time skewness on a
// faketls timeout verification.
DefaultTolerateTimeSkewness = 3 * time.Second
// DefaultPreferIP is a default value for Telegram IP connectivity
// preference.
// DefaultPreferIP is a default value for Telegram IP connectivity preference.
DefaultPreferIP = "prefer-ipv6"
// SecretKeyLength defines a length of the secret bytes used
// by Telegram and a proxy.
// SecretKeyLength defines a length of the secret bytes used by Telegram and a
// proxy.
SecretKeyLength = 16
// ConnectionIDBytesLength defines a count of random bytes used to generate
// a stream/connection ids.
// ConnectionIDBytesLength defines a count of random bytes used to generate a
// stream/connection ids.
ConnectionIDBytesLength = 16
// TCPRelayReadTimeout defines a max time period between two consecuitive
@@ -104,81 +101,76 @@ const (
TCPRelayReadTimeout = 20 * time.Second
)
// Network defines a knowledge how to work with a network. It may sound
// fun but it encapsulates all the knowledge how to properly establish
// connections to remote hosts and configure HTTP clients.
// Network defines a knowledge how to work with a network. It may sound fun but
// it encapsulates all the knowledge how to properly establish connections to
// remote hosts and configure HTTP clients.
//
// For example, if you want to use SOCKS5 proxy, you probably want to
// have all traffic routed to this proxy: telegram connections, http
// requests and so on. This knowledge is encapsulated into instances of
// such interface.
// For example, if you want to use SOCKS5 proxy, you probably want to have all
// traffic routed to this proxy: telegram connections, http requests and so on.
// This knowledge is encapsulated into instances of such interface.
//
// mtglib uses Network for:
//
// 1. Dialing to Telegram
//
// 2. Dialing to front domain
//
// 3. Doing HTTP requests (for example, for FireHOL ipblocklist).
// 1. Dialing to Telegram
// 2. Dialing to front domain
// 3. Doing HTTP requests (for example, for FireHOL ipblocklist).
type Network interface {
// Dial establishes context-free TCP connections.
Dial(network, address string) (essentials.Conn, error)
// DialContext dials using a context. This is a preferrable
// way of establishing TCP connections.
// DialContext dials using a context. This is a preferrable way of
// establishing TCP connections.
DialContext(ctx context.Context, network, address string) (essentials.Conn, error)
// MakeHTTPClient build an HTTP client with given dial function. If
// nothing is provided, then DialContext of this interface is going
// to be used.
// MakeHTTPClient build an HTTP client with given dial function. If nothing is
// provided, then DialContext of this interface is going to be used.
MakeHTTPClient(func(ctx context.Context, network, address string) (essentials.Conn, error)) *http.Client
}
// AntiReplayCache is an interface that is used to detect replay attacks
// based on some traffic fingerprints.
// AntiReplayCache is an interface that is used to detect replay attacks based
// on some traffic fingerprints.
//
// Replay attacks are probe attacks whose main goal is to identify if
// server software can be classified in some way. For example, if you
// send some HTTP request to a web server, then you can expect that this
// server will respond with HTTP response back.
// Replay attacks are probe attacks whose main goal is to identify if server
// software can be classified in some way. For example, if you send some HTTP
// request to a web server, then you can expect that this server will respond
// with HTTP response back.
//
// There is a problem though. Let's imagine, that connection is
// encrypted. Let's imagine, that it is encrypted with some static key
// like ShadowSocks (https://shadowsocks.org/assets/whitepaper.pdf).
// In that case, in theory, if you repeat the same bytes, you can get
// the same responses. Let's imagine, that you've cracked the key. then
// if you send the same bytes, you can decrypt a response and see its
// structure. Based on its structure you can identify if this server is
// SOCKS5, MTPROTO proxy etc.
// There is a problem though. Let's imagine, that connection is encrypted.
// Let's imagine, that it is encrypted with some static key like [ShadowSocks].
// In that case, in theory, if you repeat the same bytes, you can get the same
// responses. Let's imagine, that you've cracked the key. then if you send the
// same bytes, you can decrypt a response and see its structure. Based on its
// structure you can identify if this server is SOCKS5, MTPROTO proxy etc.
//
// This is just one example, maybe not the best or not the most
// relevant. In real life, different organizations use such replay
// attacks to perform some reverse engineering of the proxy, do some
// statical analysis to identify server software.
// This is just one example, maybe not the best or not the most relevant. In
// real life, different organizations use such replay attacks to perform some
// reverse engineering of the proxy, do some statical analysis to identify
// server software.
//
// There are many ways how to protect your proxy against them. One
// is domain fronting which is a core part of mtg. Another one is to
// collect some 'handshake fingerprints' and forbid duplication.
// There are many ways how to protect your proxy against them. One is domain
// fronting which is a core part of mtg. Another one is to collect some
// 'handshake fingerprints' and forbid duplication.
//
// So, it one is sending the same byte flow right after you (or a couple
// of hours after), mtg should detect that and reject this connection
// (or redirect to fronting domain).
// So, it one is sending the same byte flow right after you (or a couple of
// hours after), mtg should detect that and reject this connection (or redirect
// to fronting domain).
//
// [ShadowSocks]: https://shadowsocks.org/assets/whitepaper.pdf
type AntiReplayCache interface {
// Seen before checks if this set of bytes was observed before or
// not. If it is required to store this information somewhere else,
// then it has to do that.
// Seen before checks if this set of bytes was observed before or not. If it
// is required to store this information somewhere else, then it has to do
// that.
SeenBefore(data []byte) bool
}
// IPBlocklist filters requests based on IP address.
//
// If this filter has an IP address, then mtg closes a request without
// reading anything from a socket. It also does not give such request to
// a worker pool, so in worst cases you can expect that you invoke this
// object more frequent than defined proxy concurrency.
// If this filter has an IP address, then mtg closes a request without reading
// anything from a socket. It also does not give such request to a worker pool,
// so in worst cases you can expect that you invoke this object more frequent
// than defined proxy concurrency.
type IPBlocklist interface {
// Contains checks if given IP address belongs to this blocklist If.
// it is, a connection is terminated .
// Contains checks if given IP address belongs to this blocklist If. it is, a
// connection is terminated .
Contains(net.IP) bool
// Run starts a background update procedure for a blocklist
@@ -188,40 +180,35 @@ type IPBlocklist interface {
Shutdown()
}
// Event is a data structure which is populated during mtg request
// processing lifecycle. Each request popluates many events:
// Event is a data structure which is populated during mtg request processing
// lifecycle. Each request popluates many events:
// 1. Client connected
// 2. Request is finished
// 3. Connection to Telegram server is established
//
// 1. Client connected
//
// 2. Request is finished
//
// 3. Connection to Telegram server is established
//
// and so on. All these events are data structures but all of them
// must conform the same interface.
// and so on. All these events are data structures but all of them must conform
// the same interface.
type Event interface {
// StreamID returns an identifier of the stream, connection,
// request, you name it. All events within the same stream returns
// the same stream id.
// StreamID returns an identifier of the stream, connection, request, you name
// it. All events within the same stream returns the same stream id.
StreamID() string
// Timestamp returns a timestamp when this event was generated.
Timestamp() time.Time
}
// EventStream is an abstraction that accepts a set of events produced
// by mtg. Its main goal is to inject your logging or monitoring system.
// EventStream is an abstraction that accepts a set of events produced by mtg.
// Its main goal is to inject your logging or monitoring system.
//
// The idea is simple. When mtg works, it emits a set of events during
// a lifecycle of the requestor: EventStart, EventFinish etc. mtg is a
// producer which puts these events into a stream. Responsibility of
// the stream is to deliver this event to consumers/observers. There
// might be many different observers (for example, you want to have both
// statsd and prometheus), mtg should know nothing about them.
// The idea is simple. When mtg works, it emits a set of events during a
// lifecycle of the requestor: EventStart, EventFinish etc. mtg is a producer
// which puts these events into a stream. Responsibility of the stream is to
// deliver this event to consumers/observers. There might be many different
// observers (for example, you want to have both statsd and prometheus), mtg
// should know nothing about them.
type EventStream interface {
// Send delivers an event to observers. Given context has to be
// respected. If the context is closed, all blocking operations should
// be released ASAP.
// Send delivers an event to observers. Given context has to be respected. If
// the context is closed, all blocking operations should be released ASAP.
//
// It is possible that context is closed but the message is delivered.
// EventStream implementations should solve this issue somehow.
@@ -230,27 +217,26 @@ type EventStream interface {
// Logger defines an interface of the logger used by mtglib.
//
// Each logger has a name. It is possible to stack names to organize
// poor-man namespaces. Also, each logger must be able to bind
// parameters to avoid pushing them all the time.
// Each logger has a name. It is possible to stack names to organize poor-man
// namespaces. Also, each logger must be able to bind parameters to avoid
// pushing them all the time.
//
// Example
//
// logger := SomeLogger{}
// logger = logger.BindStr("ip", net.IP{127, 0, 0, 1})
// logger.Info("Hello")
// logger := SomeLogger{} logger = logger.BindStr("ip", net.IP{127, 0, 0, 1})
// logger.Info("Hello")
//
// In that case, ip is bound as a parameter. It is a great idea to
// put this parameter somewhere in a log message.
// In that case, ip is bound as a parameter. It is a great idea to put this
// parameter somewhere in a log message.
//
// logger1 = logger.BindStr("param1", "11")
// logger2 = logger.BindInt("param2", 11)
// logger1 = logger.BindStr("param1", "11") logger2 = logger.BindInt("param2",
// 11)
//
// logger1 should see no param2 and vice versa, logger2 should not see param1
// If you attach a parameter to a logger, parents should not know about that.
type Logger interface {
// Named returns a new logger with a bound name. Name chaining is
// allowed and appreciated.
// Named returns a new logger with a bound name. Name chaining is allowed and
// appreciated.
Named(name string) Logger
// BindInt binds new integer parameter to a new logger instance.
@@ -268,22 +254,21 @@ type Logger interface {
// Info puts a message about some normal situation.
Info(msg string)
// InfoError puts a message about some normal situation but this
// situation is related to a given error.
// InfoError puts a message about some normal situation but this situation is
// related to a given error.
InfoError(msg string, err error)
// Warning puts a message about some extraordinary situation
// worth to look at.
// Warning puts a message about some extraordinary situation worth to look at.
Warning(msg string)
// WarningError puts a message about some extraordinary situation
// worth to look at. This situation is related to a given error.
// WarningError puts a message about some extraordinary situation worth to
// look at. This situation is related to a given error.
WarningError(msg string, err error)
// Debug puts a message useful for debugging only.
Debug(msg string)
// Debug puts a message useful for debugging only. This message is
// related to a given error.
// Debug puts a message useful for debugging only. This message is related to
// a given error.
DebugError(msg string, err error)
}
+4 -4
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@@ -44,8 +44,8 @@ func (p *Proxy) DomainFrontingAddress() string {
return net.JoinHostPort(p.secret.Host, strconv.Itoa(p.domainFrontingPort))
}
// ServeConn serves a connection. We do not check IP blocklist and
// concurrency limit here.
// ServeConn serves a connection. We do not check IP blocklist and concurrency
// limit here.
func (p *Proxy) ServeConn(conn essentials.Conn) {
p.streamWaitGroup.Add(1)
defer p.streamWaitGroup.Done()
@@ -138,8 +138,8 @@ func (p *Proxy) Serve(listener net.Listener) error {
}
}
// Shutdown 'gracefully' shutdowns all connections. Please remember that
// it does not close an underlying listener.
// Shutdown 'gracefully' shutdowns all connections. Please remember that it
// does not close an underlying listener.
func (p *Proxy) Shutdown() {
p.ctxCancel()
p.streamWaitGroup.Wait()
+25 -29
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@@ -4,16 +4,16 @@ import "time"
// ProxyOpts is a structure with settings to mtg proxy.
//
// This is not required per se, but this is to shorten function
// signature and give an ability to conveniently provide default values.
// This is not required per se, but this is to shorten function signature and
// give an ability to conveniently provide default values.
type ProxyOpts struct {
// Secret defines a secret which should be used by a proxy.
//
// This is a mandatory setting.
Secret Secret
// Network defines a network instance which should be used for all
// network communications made by proxies.
// Network defines a network instance which should be used for all network
// communications made by proxies.
//
// This is a mandatory setting.
Network Network
@@ -45,9 +45,8 @@ type ProxyOpts struct {
// BufferSize is a size of the copy buffer in bytes.
//
// Please remember that we multiply this number in 2, because when
// we relay between proxies, we have to create 2 intermediate
// buffers: to and from.
// Please remember that we multiply this number in 2, because when we relay
// between proxies, we have to create 2 intermediate buffers: to and from.
//
// This is an optional setting.
//
@@ -62,22 +61,20 @@ type ProxyOpts struct {
// This is an optional setting.
Concurrency uint
// IdleTimeout is a timeout for relay when we have to break a
// stream.
// IdleTimeout is a timeout for relay when we have to break a stream.
//
// This is a timeout for any activity. So, if we have any message
// which will pass to either direction, a timer is reset. If we have
// no any reads or writes for this timeout, a connection will be
// aborted.
// This is a timeout for any activity. So, if we have any message which will
// pass to either direction, a timer is reset. If we have no any reads or
// writes for this timeout, a connection will be aborted.
//
// This is an optional setting.
IdleTimeout time.Duration
// TolerateTimeSkewness is a time boundary that defines a time
// range where faketls timestamp is acceptable.
// TolerateTimeSkewness is a time boundary that defines a time range where
// faketls timestamp is acceptable.
//
// This means that if if you got a timestamp X, now is Y, then
// if |X-Y| < TolerateTimeSkewness, then you accept a packet.
// This means that if if you got a timestamp X, now is Y, then if |X-Y| <
// TolerateTimeSkewness, then you accept a packet.
//
// This is an optional setting.
TolerateTimeSkewness time.Duration
@@ -88,30 +85,29 @@ type ProxyOpts struct {
// This is an optional setting.
PreferIP string
// DomainFrontingPort is a port we use to connect to a fronting
// domain.
// DomainFrontingPort is a port we use to connect to a fronting domain.
//
// This is required because secret does not specify a port. It
// specifies a hostname only.
// This is required because secret does not specify a port. It specifies a
// hostname only.
//
// This is an optional setting.
DomainFrontingPort uint
// AllowFallbackOnUnknownDC defines how proxy behaves if unknown DC was
// requested. If this setting is set to false, then such connection
// will be rejected. Otherwise, proxy will chose any DC.
// requested. If this setting is set to false, then such connection will be
// rejected. Otherwise, proxy will chose any DC.
//
// Telegram is designed in a way that any DC can serve any request,
// the problem is a latency.
// Telegram is designed in a way that any DC can serve any request, the
// problem is a latency.
//
// This is an optional setting.
AllowFallbackOnUnknownDC bool
// UseTestDCs defines if we have to connect to production or to staging
// DCs of Telegram.
// UseTestDCs defines if we have to connect to production or to staging DCs of
// Telegram.
//
// This is required if you use mtglib as an integration library for
// your Telegram-related projects.
// This is required if you use mtglib as an integration library for your
// Telegram-related projects.
//
// This is an optional setting.
UseTestDCs bool
+17 -18
View File
@@ -17,28 +17,27 @@ var secretEmptyKey [SecretKeyLength]byte
// "ee367a189aee18fa31c190054efd4a8e9573746f726167652e676f6f676c65617069732e636f6d".
// Actually, this is a serialized datastructure of 2 parts: key and host.
//
// ee367a189aee18fa31c190054efd4a8e9573746f726167652e676f6f676c65617069732e636f6d
// |-|-------------------------------|-------------------------------------------
// p key hostname
// ee367a189aee18fa31c190054efd4a8e9573746f726167652e676f6f676c65617069732e636f6d
// |-|-------------------------------|-------------------------------------------
// p key hostname
//
// Serialized secret starts with 'ee'. Actually, in the past we also had
// 'dd' secrets and prefixless ones. But this is history. Currently,
// we do have only 'ee' secrets which mean faketls + protection from
// statistical attacks on a length. 'ee' is a byte 238 (0xee).
// Serialized secret starts with 'ee'. Actually, in the past we also had 'dd'
// secrets and prefixless ones. But this is history. Currently, we do have only
// 'ee' secrets which mean faketls + protection from statistical attacks on a
// length. 'ee' is a byte 238 (0xee).
//
// After that, we have 16 bytes of the key. This is a random generated
// secret data of the proxy and this data is used to derive
// authentication schemas. These secrets are mixed into hmacs and sha256
// checksums which are used to build AEAD ciphers for obfuscated2
// protocol and ensure faketls handshake.
// After that, we have 16 bytes of the key. This is a random generated secret
// data of the proxy and this data is used to derive authentication schemas.
// These secrets are mixed into hmacs and sha256 checksums which are used to
// build AEAD ciphers for obfuscated2 protocol and ensure faketls handshake.
//
// Host is a domain fronting hostname in latin1 (ASCII) encoding. This
// hostname should be used for SNI in faketls and MTG verifies it. Also,
// this is when mtg gets about a domain fronting hostname.
// Host is a domain fronting hostname in latin1 (ASCII) encoding. This hostname
// should be used for SNI in faketls and MTG verifies it. Also, this is when
// mtg gets about a domain fronting hostname.
//
// Secrets can be serialized into 2 forms: hex and base64. If
// you decode both forms into bytes, you'll get the same byte array.
// Telegram clients nowadays accept all forms.
// Secrets can be serialized into 2 forms: hex and base64. If you decode both
// forms into bytes, you'll get the same byte array. Telegram clients nowadays
// accept all forms.
type Secret struct {
// Key is a set of bytes used for traffic authentication.
Key [SecretKeyLength]byte