You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
371 lines
18 KiB
371 lines
18 KiB
8 months ago
|
#if !BESTHTTP_DISABLE_PROXY
|
||
|
|
using System;
|
||
|
|
using System.IO;
|
||
|
|
using System.Text;
|
||
|
|
using BestHTTP.Authentication;
|
||
|
|
using BestHTTP.Extensions;
|
||
|
|
using BestHTTP.PlatformSupport.Memory;
|
||
|
|
|
||
|
|
namespace BestHTTP
|
||
|
|
{
|
||
|
|
internal enum SOCKSVersions : byte
|
||
|
|
{
|
||
|
|
Unknown = 0x00,
|
||
|
|
V5 = 0x05
|
||
|
|
}
|
||
|
|
|
||
|
|
/// <summary>
|
||
|
|
/// https://tools.ietf.org/html/rfc1928
|
||
|
|
/// The values currently defined for METHOD are:
|
||
|
|
/// o X'00' NO AUTHENTICATION REQUIRED
|
||
|
|
/// o X'01' GSSAPI
|
||
|
|
/// o X'02' USERNAME/PASSWORD
|
||
|
|
/// o X'03' to X'7F' IANA ASSIGNED
|
||
|
|
/// o X'80' to X'FE' RESERVED FOR PRIVATE METHODS
|
||
|
|
/// o X'FF' NO ACCEPTABLE METHODS
|
||
|
|
/// </summary>
|
||
|
|
internal enum SOCKSMethods : byte
|
||
|
|
{
|
||
|
|
NoAuthenticationRequired = 0x00,
|
||
|
|
GSSAPI = 0x01,
|
||
|
|
UsernameAndPassword = 0x02,
|
||
|
|
NoAcceptableMethods = 0xFF
|
||
|
|
}
|
||
|
|
|
||
|
|
internal enum SOCKSReplies : byte
|
||
|
|
{
|
||
|
|
Succeeded = 0x00,
|
||
|
|
GeneralSOCKSServerFailure = 0x01,
|
||
|
|
ConnectionNotAllowedByRuleset = 0x02,
|
||
|
|
NetworkUnreachable = 0x03,
|
||
|
|
HostUnreachable = 0x04,
|
||
|
|
ConnectionRefused = 0x05,
|
||
|
|
TTLExpired = 0x06,
|
||
|
|
CommandNotSupported = 0x07,
|
||
|
|
AddressTypeNotSupported = 0x08
|
||
|
|
}
|
||
|
|
|
||
|
|
internal enum SOCKSAddressTypes
|
||
|
|
{
|
||
|
|
IPV4 = 0x00,
|
||
|
|
DomainName = 0x03,
|
||
|
|
IPv6 = 0x04
|
||
|
|
}
|
||
|
|
|
||
|
|
public sealed class SOCKSProxy : Proxy
|
||
|
|
{
|
||
|
|
public SOCKSProxy(Uri address, Credentials credentials)
|
||
|
|
: base(address, credentials)
|
||
|
|
{ }
|
||
|
|
|
||
|
|
internal override string GetRequestPath(Uri uri)
|
||
|
|
{
|
||
|
|
return uri.GetRequestPathAndQueryURL();
|
||
|
|
}
|
||
|
|
|
||
|
|
internal override bool SetupRequest(HTTPRequest request)
|
||
|
|
{
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
internal override void Connect(Stream stream, HTTPRequest request)
|
||
|
|
{
|
||
|
|
var buffer = BufferPool.Get(1024, true);
|
||
|
|
try
|
||
|
|
{
|
||
|
|
int count = 0;
|
||
|
|
|
||
|
|
// https://tools.ietf.org/html/rfc1928
|
||
|
|
// The client connects to the server, and sends a version
|
||
|
|
// identifier/method selection message:
|
||
|
|
//
|
||
|
|
// +----+----------+----------+
|
||
|
|
// |VER | NMETHODS | METHODS |
|
||
|
|
// +----+----------+----------+
|
||
|
|
// | 1 | 1 | 1 to 255 |
|
||
|
|
// +----+----------+----------+
|
||
|
|
//
|
||
|
|
// The VER field is set to X'05' for this version of the protocol. The
|
||
|
|
// NMETHODS field contains the number of method identifier octets that
|
||
|
|
// appear in the METHODS field.
|
||
|
|
//
|
||
|
|
|
||
|
|
buffer[count++] = (byte)SOCKSVersions.V5;
|
||
|
|
if (this.Credentials != null)
|
||
|
|
{
|
||
|
|
buffer[count++] = 0x02; // method count
|
||
|
|
buffer[count++] = (byte)SOCKSMethods.UsernameAndPassword;
|
||
|
|
buffer[count++] = (byte)SOCKSMethods.NoAuthenticationRequired;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
buffer[count++] = 0x01; // method count
|
||
|
|
buffer[count++] = (byte)SOCKSMethods.NoAuthenticationRequired;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (HTTPManager.Logger.Level == Logger.Loglevels.All)
|
||
|
|
HTTPManager.Logger.Information("SOCKSProxy", string.Format("Sending method negotiation - count: {0} buffer: {1} ", count.ToString(), BufferToHexStr(buffer, count)), request.Context);
|
||
|
|
|
||
|
|
// Write negotiation
|
||
|
|
stream.Write(buffer, 0, count);
|
||
|
|
// Read result
|
||
|
|
count = stream.Read(buffer, 0, buffer.Length);
|
||
|
|
|
||
|
|
if (HTTPManager.Logger.Level == Logger.Loglevels.All)
|
||
|
|
HTTPManager.Logger.Information("SOCKSProxy", string.Format("Negotiation response - count: {0} buffer: {1} ", count.ToString(), BufferToHexStr(buffer, count)), request.Context);
|
||
|
|
|
||
|
|
// The server selects from one of the methods given in METHODS, and
|
||
|
|
// sends a METHOD selection message:
|
||
|
|
//
|
||
|
|
// +----+--------+
|
||
|
|
// |VER | METHOD |
|
||
|
|
// +----+--------+
|
||
|
|
// | 1 | 1 |
|
||
|
|
// +----+--------+
|
||
|
|
//
|
||
|
|
// If the selected METHOD is X'FF', none of the methods listed by the
|
||
|
|
// client are acceptable, and the client MUST close the connection.
|
||
|
|
//
|
||
|
|
// The values currently defined for METHOD are:
|
||
|
|
//
|
||
|
|
// o X'00' NO AUTHENTICATION REQUIRED
|
||
|
|
// o X'01' GSSAPI
|
||
|
|
// o X'02' USERNAME/PASSWORD
|
||
|
|
// o X'03' to X'7F' IANA ASSIGNED
|
||
|
|
// o X'80' to X'FE' RESERVED FOR PRIVATE METHODS
|
||
|
|
// o X'FF' NO ACCEPTABLE METHODS
|
||
|
|
//
|
||
|
|
// The client and server then enter a method-specific sub-negotiation.
|
||
|
|
|
||
|
|
SOCKSVersions version = (SOCKSVersions)buffer[0];
|
||
|
|
SOCKSMethods method = (SOCKSMethods)buffer[1];
|
||
|
|
|
||
|
|
// Expected result:
|
||
|
|
// 1.) Received bytes' count is 2: version + preferred method
|
||
|
|
// 2.) Version must be 5
|
||
|
|
// 3.) Preferred method must NOT be 0xFF
|
||
|
|
if (count != 2)
|
||
|
|
throw new Exception(string.Format("SOCKS Proxy - Expected read count: 2! count: {0} buffer: {1}" + count.ToString(), BufferToHexStr(buffer, count)));
|
||
|
|
else if (version != SOCKSVersions.V5)
|
||
|
|
throw new Exception("SOCKS Proxy - Expected version: 5, received version: " + buffer[0].ToString("X2"));
|
||
|
|
else if (method == SOCKSMethods.NoAcceptableMethods)
|
||
|
|
throw new Exception("SOCKS Proxy - Received 'NO ACCEPTABLE METHODS' (0xFF)");
|
||
|
|
else
|
||
|
|
{
|
||
|
|
HTTPManager.Logger.Information("SOCKSProxy", "Method negotiation over. Method: " + method.ToString(), request.Context);
|
||
|
|
switch (method)
|
||
|
|
{
|
||
|
|
case SOCKSMethods.NoAuthenticationRequired:
|
||
|
|
// nothing to do
|
||
|
|
break;
|
||
|
|
|
||
|
|
case SOCKSMethods.UsernameAndPassword:
|
||
|
|
if (this.Credentials.UserName.Length > 255)
|
||
|
|
throw new Exception(string.Format("SOCKS Proxy - Credentials.UserName too long! {0} > 255", this.Credentials.UserName.Length.ToString()));
|
||
|
|
if (this.Credentials.Password.Length > 255)
|
||
|
|
throw new Exception(string.Format("SOCKS Proxy - Credentials.Password too long! {0} > 255", this.Credentials.Password.Length.ToString()));
|
||
|
|
|
||
|
|
// https://tools.ietf.org/html/rfc1929 : Username/Password Authentication for SOCKS V5
|
||
|
|
// Once the SOCKS V5 server has started, and the client has selected the
|
||
|
|
// Username/Password Authentication protocol, the Username/Password
|
||
|
|
// subnegotiation begins. This begins with the client producing a
|
||
|
|
// Username/Password request:
|
||
|
|
//
|
||
|
|
// +----+------+----------+------+----------+
|
||
|
|
// |VER | ULEN | UNAME | PLEN | PASSWD |
|
||
|
|
// +----+------+----------+------+----------+
|
||
|
|
// | 1 | 1 | 1 to 255 | 1 | 1 to 255 |
|
||
|
|
// +----+------+----------+------+----------+
|
||
|
|
|
||
|
|
HTTPManager.Logger.Information("SOCKSProxy", "starting sub-negotiation", request.Context);
|
||
|
|
count = 0;
|
||
|
|
buffer[count++] = 0x01; // version of sub negotiation
|
||
|
|
|
||
|
|
WriteString(buffer, ref count, this.Credentials.UserName);
|
||
|
|
WriteString(buffer, ref count, this.Credentials.Password);
|
||
|
|
|
||
|
|
if (HTTPManager.Logger.Level == Logger.Loglevels.All)
|
||
|
|
HTTPManager.Logger.Information("SOCKSProxy", string.Format("Sending username and password sub-negotiation - count: {0} buffer: {1} ", count.ToString(), BufferToHexStr(buffer, count)), request.Context);
|
||
|
|
|
||
|
|
// Write negotiation
|
||
|
|
stream.Write(buffer, 0, count);
|
||
|
|
// Read result
|
||
|
|
count = stream.Read(buffer, 0, buffer.Length);
|
||
|
|
|
||
|
|
if (HTTPManager.Logger.Level == Logger.Loglevels.All)
|
||
|
|
HTTPManager.Logger.Information("SOCKSProxy", string.Format("Username and password sub-negotiation response - count: {0} buffer: {1} ", count.ToString(), BufferToHexStr(buffer, count)), request.Context);
|
||
|
|
|
||
|
|
// The server verifies the supplied UNAME and PASSWD, and sends the
|
||
|
|
// following response:
|
||
|
|
//
|
||
|
|
// +----+--------+
|
||
|
|
// |VER | STATUS |
|
||
|
|
// +----+--------+
|
||
|
|
// | 1 | 1 |
|
||
|
|
// +----+--------+
|
||
|
|
|
||
|
|
// A STATUS field of X'00' indicates success. If the server returns a
|
||
|
|
// `failure' (STATUS value other than X'00') status, it MUST close the
|
||
|
|
// connection.
|
||
|
|
bool success = buffer[1] == 0;
|
||
|
|
|
||
|
|
if (count != 2)
|
||
|
|
throw new Exception(string.Format("SOCKS Proxy - Expected read count: 2! count: {0} buffer: {1}" + count.ToString(), BufferToHexStr(buffer, count)));
|
||
|
|
else if (!success)
|
||
|
|
throw new Exception("SOCKS proxy: username+password authentication failed!");
|
||
|
|
|
||
|
|
HTTPManager.Logger.Information("SOCKSProxy", "Authenticated!", request.Context);
|
||
|
|
break;
|
||
|
|
|
||
|
|
case SOCKSMethods.GSSAPI:
|
||
|
|
throw new Exception("SOCKS proxy: GSSAPI not supported!");
|
||
|
|
|
||
|
|
case SOCKSMethods.NoAcceptableMethods:
|
||
|
|
throw new Exception("SOCKS proxy: No acceptable method");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// The SOCKS request is formed as follows:
|
||
|
|
//
|
||
|
|
// +----+-----+-------+------+----------+----------+
|
||
|
|
// |VER | CMD | RSV | ATYP | DST.ADDR | DST.PORT |
|
||
|
|
// +----+-----+-------+------+----------+----------+
|
||
|
|
// | 1 | 1 | X'00' | 1 | Variable | 2 |
|
||
|
|
// +----+-----+-------+------+----------+----------+
|
||
|
|
//
|
||
|
|
// Where:
|
||
|
|
//
|
||
|
|
// o VER protocol version: X'05'
|
||
|
|
// o CMD
|
||
|
|
// o CONNECT X'01'
|
||
|
|
// o BIND X'02'
|
||
|
|
// o UDP ASSOCIATE X'03'
|
||
|
|
// o RSV RESERVED
|
||
|
|
// o ATYP address type of following address
|
||
|
|
// o IP V4 address: X'01'
|
||
|
|
// o DOMAINNAME: X'03'
|
||
|
|
// o IP V6 address: X'04'
|
||
|
|
// o DST.ADDR desired destination address
|
||
|
|
// o DST.PORT desired destination port in network octet
|
||
|
|
// order
|
||
|
|
|
||
|
|
count = 0;
|
||
|
|
buffer[count++] = (byte)SOCKSVersions.V5; // version: 5
|
||
|
|
buffer[count++] = 0x01; // command: connect
|
||
|
|
buffer[count++] = 0x00; // reserved, bust be 0x00
|
||
|
|
|
||
|
|
if (request.CurrentUri.IsHostIsAnIPAddress())
|
||
|
|
{
|
||
|
|
bool isIPV4 = Extensions.Extensions.IsIpV4AddressValid(request.CurrentUri.Host);
|
||
|
|
buffer[count++] = isIPV4 ? (byte)SOCKSAddressTypes.IPV4 : (byte)SOCKSAddressTypes.IPv6;
|
||
|
|
|
||
|
|
var ipAddress = System.Net.IPAddress.Parse(request.CurrentUri.Host);
|
||
|
|
var ipBytes = ipAddress.GetAddressBytes();
|
||
|
|
WriteBytes(buffer, ref count, ipBytes); // destination address
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
buffer[count++] = (byte)SOCKSAddressTypes.DomainName;
|
||
|
|
|
||
|
|
// The first octet of the address field contains the number of octets of name that
|
||
|
|
// follow, there is no terminating NUL octet.
|
||
|
|
WriteString(buffer, ref count, request.CurrentUri.Host);
|
||
|
|
}
|
||
|
|
|
||
|
|
// destination port in network octet order
|
||
|
|
buffer[count++] = (byte)((request.CurrentUri.Port >> 8) & 0xFF);
|
||
|
|
buffer[count++] = (byte)(request.CurrentUri.Port & 0xFF);
|
||
|
|
|
||
|
|
if (HTTPManager.Logger.Level == Logger.Loglevels.All)
|
||
|
|
HTTPManager.Logger.Information("SOCKSProxy", string.Format("Sending connect request - count: {0} buffer: {1} ", count.ToString(), BufferToHexStr(buffer, count)), request.Context);
|
||
|
|
|
||
|
|
stream.Write(buffer, 0, count);
|
||
|
|
count = stream.Read(buffer, 0, buffer.Length);
|
||
|
|
|
||
|
|
if (HTTPManager.Logger.Level == Logger.Loglevels.All)
|
||
|
|
HTTPManager.Logger.Information("SOCKSProxy", string.Format("Connect response - count: {0} buffer: {1} ", count.ToString(), BufferToHexStr(buffer, count)), request.Context);
|
||
|
|
|
||
|
|
// The SOCKS request information is sent by the client as soon as it has
|
||
|
|
// established a connection to the SOCKS server, and completed the
|
||
|
|
// authentication negotiations. The server evaluates the request, and
|
||
|
|
// returns a reply formed as follows:
|
||
|
|
//
|
||
|
|
// +----+-----+-------+------+----------+----------+
|
||
|
|
// |VER | REP | RSV | ATYP | BND.ADDR | BND.PORT |
|
||
|
|
// +----+-----+-------+------+----------+----------+
|
||
|
|
// | 1 | 1 | X'00' | 1 | Variable | 2 |
|
||
|
|
// +----+-----+-------+------+----------+----------+
|
||
|
|
//
|
||
|
|
// Where:
|
||
|
|
// o VER protocol version: X'05'
|
||
|
|
// o REP Reply field:
|
||
|
|
// o X'00' succeeded
|
||
|
|
// o X'01' general SOCKS server failure
|
||
|
|
// o X'02' connection not allowed by ruleset
|
||
|
|
// o X'03' Network unreachable
|
||
|
|
// o X'04' Host unreachable
|
||
|
|
// o X'05' Connection refused
|
||
|
|
// o X'06' TTL expired
|
||
|
|
// o X'07' Command not supported
|
||
|
|
// o X'08' Address type not supported
|
||
|
|
// o X'09' to X'FF' unassigned
|
||
|
|
// o RSV RESERVED
|
||
|
|
// o ATYP address type of following address
|
||
|
|
// o IP V4 address: X'01'
|
||
|
|
// o DOMAINNAME: X'03'
|
||
|
|
// o IP V6 address: X'04'
|
||
|
|
// o BND.ADDR server bound address
|
||
|
|
// o BND.PORT server bound port in network octet order
|
||
|
|
//
|
||
|
|
// Fields marked RESERVED (RSV) must be set to X'00'.
|
||
|
|
|
||
|
|
version = (SOCKSVersions)buffer[0];
|
||
|
|
SOCKSReplies reply = (SOCKSReplies)buffer[1];
|
||
|
|
|
||
|
|
// at least 10 bytes expected as a result
|
||
|
|
if (count < 10)
|
||
|
|
throw new Exception(string.Format("SOCKS proxy: not enough data returned by the server. Expected count is at least 10 bytes, server returned {0} bytes! content: {1}", count.ToString(), BufferToHexStr(buffer, count)));
|
||
|
|
else if (reply != SOCKSReplies.Succeeded)
|
||
|
|
throw new Exception("SOCKS proxy error: " + reply.ToString());
|
||
|
|
|
||
|
|
HTTPManager.Logger.Information("SOCKSProxy", "Connected!", request.Context);
|
||
|
|
}
|
||
|
|
finally
|
||
|
|
{
|
||
|
|
BufferPool.Release(buffer);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
private void WriteString(byte[] buffer, ref int count, string str)
|
||
|
|
{
|
||
|
|
// Get the bytes
|
||
|
|
int byteCount = Encoding.UTF8.GetByteCount(str);
|
||
|
|
if (byteCount > 255)
|
||
|
|
throw new Exception(string.Format("SOCKS Proxy - String is too large ({0}) to fit in 255 bytes!", byteCount.ToString()));
|
||
|
|
|
||
|
|
// number of bytes
|
||
|
|
buffer[count++] = (byte)byteCount;
|
||
|
|
|
||
|
|
// and the bytes itself
|
||
|
|
Encoding.UTF8.GetBytes(str, 0, str.Length, buffer, count);
|
||
|
|
|
||
|
|
count += byteCount;
|
||
|
|
}
|
||
|
|
|
||
|
|
private void WriteBytes(byte[] buffer, ref int count, byte[] bytes)
|
||
|
|
{
|
||
|
|
Array.Copy(bytes, 0, buffer, count, bytes.Length);
|
||
|
|
count += bytes.Length;
|
||
|
|
}
|
||
|
|
|
||
|
|
private string BufferToHexStr(byte[] buffer, int count)
|
||
|
|
{
|
||
|
|
StringBuilder sb = new StringBuilder(count * 2);
|
||
|
|
for (int i = 0; i < count; ++i)
|
||
|
|
sb.AppendFormat("0x{0} ", buffer[i].ToString("X2"));
|
||
|
|
return sb.ToString();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
#endif
|