SigHelper: Fix many issues

This commit is contained in:
Samantaz Fox 2024-07-03 18:20:35 +02:00
parent ec8b7916fa
commit b509aa91d5
No known key found for this signature in database
GPG Key ID: F42821059186176E
2 changed files with 133 additions and 102 deletions

View File

@ -3,6 +3,10 @@ require "socket"
require "socket/tcp_socket"
require "socket/unix_socket"
{% if flag?(:advanced_debug) %}
require "io/hexdump"
{% end %}
private alias NetworkEndian = IO::ByteFormat::NetworkEndian
class Invidious::SigHelper
@ -20,30 +24,34 @@ class Invidious::SigHelper
end
struct StringPayload < Payload
getter value : String
getter string : String
def initialize(str : String)
raise Exception.new("SigHelper: String can't be empty") if str.empty?
@value = str
@string = str
end
def self.from_io(io : IO)
size = io.read_bytes(UInt16, NetworkEndian)
def self.from_bytes(slice : Bytes)
size = IO::ByteFormat::NetworkEndian.decode(UInt16, slice)
if size == 0 # Error code
raise Exception.new("SigHelper: Server encountered an error")
end
if str = io.gets(limit: size)
if (slice.bytesize - 2) != size
raise Exception.new("SigHelper: String size mismatch")
end
if str = String.new(slice[2..])
return self.new(str)
else
raise Exception.new("SigHelper: Can't read string from socket")
end
end
def self.to_io(io : IO)
def to_io(io)
# `.to_u16` raises if there is an overflow during the conversion
io.write_bytes(@value.bytesize.to_u16, NetworkEndian)
io.write(@value.to_slice)
io.write_bytes(@string.bytesize.to_u16, NetworkEndian)
io.write(@string.to_slice)
end
end
@ -55,23 +63,24 @@ class Invidious::SigHelper
GET_PLAYER_STATUS = 4
end
private struct Request
def initialize(@opcode : Opcode, @payload : Payload?)
end
end
private record Request,
opcode : Opcode,
payload : Payload?
# ----------------------
# High-level functions
# ----------------------
module Client
extend self
# Forces the server to re-fetch the YouTube player, and extract the necessary
# components from it (nsig function code, sig function code, signature timestamp).
def force_update : UpdateStatus
request = Request.new(Opcode::FORCE_UPDATE, nil)
value = send_request(request) do |io|
io.read_bytes(UInt16, NetworkEndian)
value = send_request(request) do |bytes|
IO::ByteFormat::NetworkEndian.decode(UInt16, bytes)
end
case value
@ -79,20 +88,18 @@ class Invidious::SigHelper
when 0xFFFF then return UpdateStatus::UpdateNotRequired
when 0xF44F then return UpdateStatus::Updated
else
raise Exception.new("SigHelper: Invalid status code received")
code = value.nil? ? "nil" : value.to_s(base: 16)
raise Exception.new("SigHelper: Invalid status code received #{code}")
end
end
# Decrypt a provided n signature using the server's current nsig function
# code, and return the result (or an error).
def decrypt_n_param(n : String) : String
def decrypt_n_param(n : String) : String?
request = Request.new(Opcode::DECRYPT_N_SIGNATURE, StringPayload.new(n))
n_dec = send_request(request) do |io|
StringPayload.from_io(io).string
rescue ex
LOGGER.debug(ex.message)
nil
n_dec = send_request(request) do |bytes|
StringPayload.from_bytes(bytes).string
end
return n_dec
@ -103,11 +110,8 @@ class Invidious::SigHelper
def decrypt_sig(sig : String) : String?
request = Request.new(Opcode::DECRYPT_SIGNATURE, StringPayload.new(sig))
sig_dec = send_request(request) do |io|
StringPayload.from_io(io).string
rescue ex
LOGGER.debug(ex.message)
nil
sig_dec = send_request(request) do |bytes|
StringPayload.from_bytes(bytes).string
end
return sig_dec
@ -117,29 +121,30 @@ class Invidious::SigHelper
def get_sts : UInt64?
request = Request.new(Opcode::GET_SIGNATURE_TIMESTAMP, nil)
return send_request(request) do |io|
io.read_bytes(UInt64, NetworkEndian)
return send_request(request) do |bytes|
IO::ByteFormat::NetworkEndian.decode(UInt64, bytes)
end
end
# Return the signature timestamp from the server's current player
# Return the current player's version
def get_player : UInt32?
request = Request.new(Opcode::GET_PLAYER_STATUS, nil)
send_request(request) do |io|
has_player = io.read_bytes(UInt8) == 0xFF
player_version = io.read_bytes(UInt32, NetworkEndian)
send_request(request) do |bytes|
has_player = (bytes[0] == 0xFF)
player_version = IO::ByteFormat::NetworkEndian.decode(UInt32, bytes[1..4])
end
return has_player ? player_version : nil
end
private def send_request(request : Request, &block : IO)
channel = Multiplexor.send(request)
data_io = channel.receive
return yield data_io
private def send_request(request : Request, &)
channel = Multiplexor::INSTANCE.send(request)
slice = channel.receive
return yield slice
rescue ex
LOGGER.debug(ex.message)
LOGGER.debug("SigHelper: Error when sending a request")
LOGGER.trace(ex.inspect_with_backtrace)
return nil
end
end
@ -158,12 +163,7 @@ class Invidious::SigHelper
@conn : Connection
INSTANCE = new
def initialize
@conn = Connection.new
listen
end
INSTANCE = new("")
def initialize(url : String)
@conn = Connection.new(url)
@ -173,22 +173,24 @@ class Invidious::SigHelper
def listen : Nil
raise "Socket is closed" if @conn.closed?
LOGGER.debug("SigHelper: Multiplexor listening")
# TODO: reopen socket if unexpectedly closed
spawn do
loop do
receive_data
Fiber.sleep
Fiber.yield
end
end
end
def self.send(request : Request)
def send(request : Request)
transaction = Transaction.new
transaction_id = @prng.rand(TransactionID)
# Add transaction to queue
@mutex.synchronize do
# On a 64-bits random integer, this should never happen. Though, just in case, ...
# On a 32-bits random integer, this should never happen. Though, just in case, ...
if @queue[transaction_id]?
raise Exception.new("SigHelper: Duplicate transaction ID! You got a shiny pokemon!")
end
@ -201,75 +203,92 @@ class Invidious::SigHelper
return transaction.channel
end
def receive_data : Payload
# Read a single packet from socker
transaction_id, data_io = read_packet
def receive_data
transaction_id, slice = read_packet
# Remove transaction from queue
@mutex.synchronize do
transaction = @queue.delete(transaction_id)
if transaction = @queue.delete(transaction_id)
# Remove transaction from queue and send data to the channel
transaction.channel.send(slice)
LOGGER.trace("SigHelper: Transaction unqueued and data sent to channel")
else
raise Exception.new("SigHelper: Received transaction was not in queue")
end
end
# Send data to the channel
transaction.channel.send(data)
end
# Read a single packet from the socket
private def read_packet : {TransactionID, IO}
private def read_packet : {TransactionID, Bytes}
# Header
transaction_id = @conn.read_u32
length = conn.read_u32
transaction_id = @conn.read_bytes(UInt32, NetworkEndian)
length = @conn.read_bytes(UInt32, NetworkEndian)
LOGGER.trace("SigHelper: Recv transaction 0x#{transaction_id.to_s(base: 16)} / length #{length}")
if length > 67_000
raise Exception.new("SigHelper: Packet longer than expected (#{length})")
end
# Payload
data_io = IO::Memory.new(1024)
IO.copy(@conn, data_io, limit: length)
slice = Bytes.new(length)
@conn.read(slice) if length > 0
# data = Bytes.new()
# conn.read(data)
LOGGER.trace("SigHelper: payload = #{slice}")
LOGGER.trace("SigHelper: Recv transaction 0x#{transaction_id.to_s(base: 16)} - Done")
return transaction_id, data_io
return transaction_id, slice
end
# Write a single packet to the socket
private def write_packet(transaction_id : TransactionID, request : Request)
@conn.write_int(request.opcode)
@conn.write_int(transaction_id)
request.payload.to_io(@conn)
LOGGER.trace("SigHelper: Send transaction 0x#{transaction_id.to_s(base: 16)} / opcode #{request.opcode}")
io = IO::Memory.new(1024)
io.write_bytes(request.opcode.to_u8, NetworkEndian)
io.write_bytes(transaction_id, NetworkEndian)
if payload = request.payload
payload.to_io(io)
end
@conn.send(io)
@conn.flush
LOGGER.trace("SigHelper: Send transaction 0x#{transaction_id.to_s(base: 16)} - Done")
end
end
class Connection
@socket : UNIXSocket | TCPSocket
@mutex = Mutex.new
{% if flag?(:advanced_debug) %}
@io : IO::Hexdump
{% end %}
def initialize(host_or_path : String)
if host_or_path.empty?
host_or_path = default_path
host_or_path = "/tmp/inv_sig_helper.sock"
end
begin
case host_or_path
when .starts_with?('/')
@socket = UNIXSocket.new(host_or_path)
when .starts_with?("tcp://")
uri = URI.new(host_or_path)
@socket = TCPSocket.new(uri.host, uri.port)
@socket = TCPSocket.new(uri.host.not_nil!, uri.port.not_nil!)
else
uri = URI.new("tcp://#{host_or_path}")
@socket = TCPSocket.new(uri.host, uri.port)
@socket = TCPSocket.new(uri.host.not_nil!, uri.port.not_nil!)
end
socket.sync = false
rescue ex
raise ConnectionError.new("Connection error", cause: ex)
end
end
LOGGER.debug("SigHelper: Listening on '#{host_or_path}'")
private default_path
return "/tmp/inv_sig_helper.sock"
{% if flag?(:advanced_debug) %}
@io = IO::Hexdump.new(@socket, output: STDERR, read: true, write: true)
{% end %}
@socket.sync = false
@socket.blocking = false
end
def closed? : Bool
@ -284,20 +303,23 @@ class Invidious::SigHelper
end
end
def gets(*args, **options)
@socket.gets(*args, **options)
def flush(*args, **options)
@socket.flush(*args, **options)
end
def read_bytes(*args, **options)
@socket.read_bytes(*args, **options)
def send(*args, **options)
@socket.send(*args, **options)
end
def write(*args, **options)
@socket.write(*args, **options)
end
def write_bytes(*args, **options)
@socket.write_bytes(*args, **options)
# Wrap IO functions, with added debug tooling if needed
{% for function in %w(read read_bytes write write_bytes) %}
def {{function.id}}(*args, **options)
{% if flag?(:advanced_debug) %}
@io.{{function.id}}(*args, **options)
{% else %}
@socket.{{function.id}}(*args, **options)
{% end %}
end
{% end %}
end
end

View File

@ -17,6 +17,15 @@ struct Invidious::DecryptFunction
end
end
def decrypt_nsig(n : String) : String?
self.check_update
return SigHelper::Client.decrypt_n_param(n)
rescue ex
LOGGER.debug(ex.message || "Signature: Unknown error")
LOGGER.trace(ex.inspect_with_backtrace)
return nil
end
def decrypt_signature(str : String) : String?
self.check_update
return SigHelper::Client.decrypt_sig(str)