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SoftEtherVPN/src/Cedar/IPsec_IPC.c

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2014-01-04 17:00:08 +04:00
// SoftEther VPN Source Code
// Cedar Communication Module
//
// SoftEther VPN Server, Client and Bridge are free software under GPLv2.
//
// Copyright (c) 2012-2014 Daiyuu Nobori.
// Copyright (c) 2012-2014 SoftEther VPN Project, University of Tsukuba, Japan.
// Copyright (c) 2012-2014 SoftEther Corporation.
//
// All Rights Reserved.
//
// http://www.softether.org/
//
// Author: Daiyuu Nobori
// Comments: Tetsuo Sugiyama, Ph.D.
//
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// version 2 as published by the Free Software Foundation.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License version 2
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
// IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
// CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
// TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
// SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
// THE LICENSE AGREEMENT IS ATTACHED ON THE SOURCE-CODE PACKAGE
// AS "LICENSE.TXT" FILE. READ THE TEXT FILE IN ADVANCE TO USE THE SOFTWARE.
//
//
// THIS SOFTWARE IS DEVELOPED IN JAPAN, AND DISTRIBUTED FROM JAPAN,
// UNDER JAPANESE LAWS. YOU MUST AGREE IN ADVANCE TO USE, COPY, MODIFY,
// MERGE, PUBLISH, DISTRIBUTE, SUBLICENSE, AND/OR SELL COPIES OF THIS
// SOFTWARE, THAT ANY JURIDICAL DISPUTES WHICH ARE CONCERNED TO THIS
// SOFTWARE OR ITS CONTENTS, AGAINST US (SOFTETHER PROJECT, SOFTETHER
// CORPORATION, DAIYUU NOBORI OR OTHER SUPPLIERS), OR ANY JURIDICAL
// DISPUTES AGAINST US WHICH ARE CAUSED BY ANY KIND OF USING, COPYING,
// MODIFYING, MERGING, PUBLISHING, DISTRIBUTING, SUBLICENSING, AND/OR
// SELLING COPIES OF THIS SOFTWARE SHALL BE REGARDED AS BE CONSTRUED AND
// CONTROLLED BY JAPANESE LAWS, AND YOU MUST FURTHER CONSENT TO
// EXCLUSIVE JURISDICTION AND VENUE IN THE COURTS SITTING IN TOKYO,
// JAPAN. YOU MUST WAIVE ALL DEFENSES OF LACK OF PERSONAL JURISDICTION
// AND FORUM NON CONVENIENS. PROCESS MAY BE SERVED ON EITHER PARTY IN
// THE MANNER AUTHORIZED BY APPLICABLE LAW OR COURT RULE.
//
// USE ONLY IN JAPAN. DO NOT USE IT IN OTHER COUNTRIES. IMPORTING THIS
// SOFTWARE INTO OTHER COUNTRIES IS AT YOUR OWN RISK. SOME COUNTRIES
// PROHIBIT ENCRYPTED COMMUNICATIONS. USING THIS SOFTWARE IN OTHER
// COUNTRIES MIGHT BE RESTRICTED.
//
//
2014-01-15 13:01:42 +04:00
// SOURCE CODE CONTRIBUTION
// ------------------------
//
// Your contribution to SoftEther VPN Project is much appreciated.
// Please send patches to us through GitHub.
// Read the SoftEther VPN Patch Acceptance Policy in advance:
// http://www.softether.org/5-download/src/9.patch
//
//
2014-01-04 17:00:08 +04:00
// DEAR SECURITY EXPERTS
// ---------------------
//
// If you find a bug or a security vulnerability please kindly inform us
// about the problem immediately so that we can fix the security problem
// to protect a lot of users around the world as soon as possible.
//
// Our e-mail address for security reports is:
// softether-vpn-security [at] softether.org
//
// Please note that the above e-mail address is not a technical support
// inquiry address. If you need technical assistance, please visit
// http://www.softether.org/ and ask your question on the users forum.
//
// Thank you for your cooperation.
// IPsec_IPC.c
// In-process VPN client module
#include "CedarPch.h"
// Extract the MS-CHAP v2 authentication information by parsing the password string
bool ParseAndExtractMsChapV2InfoFromPassword(IPC_MSCHAP_V2_AUTHINFO *d, char *password)
{
TOKEN_LIST *t;
bool ret = false;
// Validate arguments
if (d == NULL || password == NULL)
{
return false;
}
Zero(d, sizeof(IPC_MSCHAP_V2_AUTHINFO));
if (StartWith(password, IPC_PASSWORD_MSCHAPV2_TAG) == false)
{
return false;
}
t = ParseTokenWithNullStr(password, ":");
if (t->NumTokens == 5)
{
BUF *b1, *b2, *b3;
b1 = StrToBin(t->Token[2]);
b2 = StrToBin(t->Token[3]);
b3 = StrToBin(t->Token[4]);
if (IsEmptyStr(t->Token[1]) == false && b1->Size == 16 && b2->Size == 16 && b3->Size == 24)
{
StrCpy(d->MsChapV2_PPPUsername, sizeof(d->MsChapV2_PPPUsername), t->Token[1]);
Copy(d->MsChapV2_ServerChallenge, b1->Buf, 16);
Copy(d->MsChapV2_ClientChallenge, b2->Buf, 16);
Copy(d->MsChapV2_ClientResponse, b3->Buf, 24);
ret = true;
}
FreeBuf(b1);
FreeBuf(b2);
FreeBuf(b3);
}
FreeToken(t);
return ret;
}
// Start an IPC connection asynchronously
IPC_ASYNC *NewIPCAsync(CEDAR *cedar, IPC_PARAM *param, SOCK_EVENT *sock_event)
{
IPC_ASYNC *a;
// Validate arguments
if (cedar == NULL || param == NULL)
{
return NULL;
}
a = ZeroMalloc(sizeof(IPC_ASYNC));
a->TubeForDisconnect = NewTube(0);
a->Cedar = cedar;
AddRef(a->Cedar->ref);
Copy(&a->Param, param, sizeof(IPC_PARAM));
if (sock_event != NULL)
{
a->SockEvent = sock_event;
AddRef(a->SockEvent->ref);
}
a->Thread = NewThread(IPCAsyncThreadProc, a);
return a;
}
// asynchronous IPC connection creation thread
void IPCAsyncThreadProc(THREAD *thread, void *param)
{
IPC_ASYNC *a;
// Validate arguments
if (thread == NULL || param == NULL)
{
return;
}
a = (IPC_ASYNC *)param;
// Attempt to connect
a->Ipc = NewIPCByParam(a->Cedar, &a->Param, &a->ErrorCode);
if (a->Ipc != NULL)
{
if (a->Param.IsL3Mode)
{
DHCP_OPTION_LIST cao;
Zero(&cao, sizeof(cao));
// Get an IP address from the DHCP server in the case of L3 mode
Debug("IPCDhcpAllocateIPEx() start...\n");
if (IPCDhcpAllocateIPEx(a->Ipc, &cao, a->TubeForDisconnect, a->Param.IsOpenVPN))
{
UINT t;
IP ip, subnet, gw;
Debug("IPCDhcpAllocateIPEx() Ok.\n");
// Calculate the DHCP update interval
t = cao.LeaseTime;
if (t == 0)
{
t = 600;
}
t = t / 3;
if (t == 0)
{
t = 1;
}
// Save the options list
Copy(&a->L3ClientAddressOption, &cao, sizeof(DHCP_OPTION_LIST));
a->L3DhcpRenewInterval = t * 1000;
// Set the obtained IP address parameters to the IPC virtual host
UINTToIP(&ip, cao.ClientAddress);
UINTToIP(&subnet, cao.SubnetMask);
UINTToIP(&gw, cao.Gateway);
IPCSetIPv4Parameters(a->Ipc, &ip, &subnet, &gw);
a->L3NextDhcpRenewTick = Tick64() + a->L3DhcpRenewInterval;
}
else
{
Debug("IPCDhcpAllocateIPEx() Error.\n");
a->DhcpAllocFailed = true;
FreeIPC(a->Ipc);
a->Ipc = NULL;
}
}
}
// Procedure complete
a->Done = true;
if (a->SockEvent != NULL)
{
SetSockEvent(a->SockEvent);
}
}
// Release the IPC asynchronous connection object
void FreeIPCAsync(IPC_ASYNC *a)
{
// Validate arguments
if (a == NULL)
{
return;
}
TubeDisconnect(a->TubeForDisconnect);
WaitThread(a->Thread, INFINITE);
ReleaseThread(a->Thread);
if (a->Ipc != NULL)
{
FreeIPC(a->Ipc);
a->Ipc = NULL;
}
if (a->SockEvent != NULL)
{
ReleaseSockEvent(a->SockEvent);
}
ReleaseCedar(a->Cedar);
ReleaseTube(a->TubeForDisconnect);
Free(a);
}
// Start a new IPC connection by specifying the parameter structure
IPC *NewIPCByParam(CEDAR *cedar, IPC_PARAM *param, UINT *error_code)
{
IPC *ipc;
// Validate arguments
if (cedar == NULL || param == NULL)
{
return NULL;
}
ipc = NewIPC(cedar, param->ClientName, param->Postfix, param->HubName,
param->UserName, param->Password, error_code, &param->ClientIp,
param->ClientPort, &param->ServerIp, param->ServerPort,
param->ClientHostname, param->CryptName,
param->BridgeMode, param->Mss);
return ipc;
}
// Start a new IPC connection
IPC *NewIPC(CEDAR *cedar, char *client_name, char *postfix, char *hubname, char *username, char *password,
UINT *error_code, IP *client_ip, UINT client_port, IP *server_ip, UINT server_port,
char *client_hostname, char *crypt_name,
bool bridge_mode, UINT mss)
{
IPC *ipc;
UINT dummy_int = 0;
SOCK *a;
SOCK *s;
PACK *p;
UINT err = ERR_INTERNAL_ERROR;
char server_str[MAX_SIZE];
char macstr[30];
UINT server_ver, server_build;
UCHAR unique[SHA1_SIZE];
NODE_INFO info;
BUF *b;
UCHAR mschap_v2_server_response_20[20];
// Validate arguments
if (cedar == NULL || username == NULL || password == NULL || client_hostname == NULL)
{
return NULL;
}
if (IsEmptyStr(client_name))
{
client_name = "InProc VPN Connection";
}
if (IsEmptyStr(crypt_name))
{
crypt_name = "";
}
if (error_code == NULL)
{
error_code = &dummy_int;
}
Zero(mschap_v2_server_response_20, sizeof(mschap_v2_server_response_20));
err = *error_code = ERR_INTERNAL_ERROR;
a = GetInProcListeningSock(cedar);
if (a == NULL)
{
return NULL;
}
ipc = ZeroMalloc(sizeof(IPC));
ipc->Cedar = cedar;
AddRef(cedar->ref);
ipc->FlushList = NewTubeFlushList();
StrCpy(ipc->ClientHostname, sizeof(ipc->ClientHostname), client_hostname);
StrCpy(ipc->HubName, sizeof(ipc->HubName), hubname);
StrCpy(ipc->UserName, sizeof(ipc->UserName), username);
StrCpy(ipc->Password, sizeof(ipc->Password), password);
// Connect the in-process socket
s = ConnectInProc(a, client_ip, client_port, server_ip, server_port);
if (s == NULL)
{
goto LABEL_ERROR;
}
// Protocol initialization process
if (ClientUploadSignature(s) == false)
{
err = ERR_DISCONNECTED;
goto LABEL_ERROR;
}
p = HttpClientRecv(s);
if (p == NULL)
{
err = ERR_DISCONNECTED;
goto LABEL_ERROR;
}
err = GetErrorFromPack(p);
if (err != ERR_NO_ERROR)
{
FreePack(p);
goto LABEL_ERROR;
}
if (GetHello(p, ipc->random, &server_ver, &server_build, server_str, sizeof(server_str)) == false)
{
FreePack(p);
err = ERR_DISCONNECTED;
goto LABEL_ERROR;
}
FreePack(p);
// Upload the authentication data
p = PackLoginWithPlainPassword(hubname, username, password);
PackAddInt64(p, "timestamp", SystemTime64());
PackAddStr(p, "hello", client_name);
PackAddInt(p, "client_ver", cedar->Version);
PackAddInt(p, "client_build", cedar->Build);
PackAddInt(p, "max_connection", 1);
PackAddInt(p, "use_encrypt", 0);
PackAddInt(p, "use_compress", 0);
PackAddInt(p, "half_connection", 0);
PackAddInt(p, "adjust_mss", mss);
PackAddBool(p, "require_bridge_routing_mode", bridge_mode);
PackAddBool(p, "require_monitor_mode", false);
PackAddBool(p, "qos", false);
// Unique ID is determined by the sum of the connecting client IP address and the client_name
b = NewBuf();
WriteBuf(b, client_ip, sizeof(IP));
WriteBufStr(b, client_name);
WriteBufStr(b, crypt_name);
HashSha1(unique, b->Buf, b->Size);
FreeBuf(b);
PackAddData(p, "unique_id", unique, SHA1_SIZE);
PackAddStr(p, "inproc_postfix", postfix);
PackAddStr(p, "inproc_cryptname", crypt_name);
// Node information
Zero(&info, sizeof(info));
StrCpy(info.ClientProductName, sizeof(info.ClientProductName), client_name);
info.ClientProductVer = Endian32(cedar->Version);
info.ClientProductBuild = Endian32(cedar->Build);
StrCpy(info.ServerProductName, sizeof(info.ServerProductName), server_str);
info.ServerProductVer = Endian32(server_ver);
info.ServerProductBuild = Endian32(server_build);
StrCpy(info.ClientOsName, sizeof(info.ClientOsName), client_name);
StrCpy(info.ClientOsVer, sizeof(info.ClientOsVer), "-");
StrCpy(info.ClientOsProductId, sizeof(info.ClientOsProductId), "-");
info.ClientIpAddress = IPToUINT(&s->LocalIP);
info.ClientPort = Endian32(s->LocalPort);
StrCpy(info.ClientHostname, sizeof(info.ClientHostname), ipc->ClientHostname);
IPToStr(info.ServerHostname, sizeof(info.ServerHostname), &s->RemoteIP);
info.ServerIpAddress = IPToUINT(&s->RemoteIP);
info.ServerPort = Endian32(s->RemotePort);
StrCpy(info.HubName, sizeof(info.HubName), hubname);
Copy(info.UniqueId, unique, 16);
if (IsIP6(&s->LocalIP))
{
Copy(info.ClientIpAddress6, s->LocalIP.ipv6_addr, 16);
}
if (IsIP6(&s->RemoteIP))
{
Copy(info.ServerIpAddress6, s->RemoteIP.ipv6_addr, 16);
}
OutRpcNodeInfo(p, &info);
if (HttpClientSend(s, p) == false)
{
FreePack(p);
err = ERR_DISCONNECTED;
goto LABEL_ERROR;
}
FreePack(p);
// Receive a Welcome packet
p = HttpClientRecv(s);
if (p == NULL)
{
err = ERR_DISCONNECTED;
goto LABEL_ERROR;
}
err = GetErrorFromPack(p);
if (err != ERR_NO_ERROR)
{
FreePack(p);
goto LABEL_ERROR;
}
if (ParseWelcomeFromPack(p, ipc->SessionName, sizeof(ipc->SessionName),
ipc->ConnectionName, sizeof(ipc->ConnectionName), &ipc->Policy) == false)
{
err = ERR_PROTOCOL_ERROR;
FreePack(p);
goto LABEL_ERROR;
}
if (PackGetData2(p, "IpcMacAddress", ipc->MacAddress, 6) == false || IsZero(ipc->MacAddress, 6))
{
err = ERR_PROTOCOL_ERROR;
FreePack(p);
goto LABEL_ERROR;
}
if (PackGetData2(p, "IpcMsChapV2ServerResponse", mschap_v2_server_response_20, sizeof(mschap_v2_server_response_20)))
{
Copy(ipc->MsChapV2_ServerResponse, mschap_v2_server_response_20, sizeof(mschap_v2_server_response_20));
}
PackGetStr(p, "IpcHubName", ipc->HubName, sizeof(ipc->HubName));
Debug("IPC Hub Name: %s\n", ipc->HubName);
MacToStr(macstr, sizeof(macstr), ipc->MacAddress);
Debug("IPC: Session = %s, Connection = %s, Mac = %s\n", ipc->SessionName, ipc->ConnectionName, macstr);
FreePack(p);
ReleaseSock(a);
ipc->Sock = s;
Debug("NewIPC() Succeed.\n");
ipc->Interrupt = NewInterruptManager();
// Create an ARP table
ipc->ArpTable = NewList(IPCCmpArpTable);
// Create an IPv4 reception queue
ipc->IPv4RecviedQueue = NewQueue();
return ipc;
LABEL_ERROR:
Debug("NewIPC() Failed: Err = %u\n", err);
Disconnect(s);
ReleaseSock(s);
ReleaseSock(a);
FreeIPC(ipc);
*error_code = err;
return NULL;
}
// Create a new IPC based on SOCK
IPC *NewIPCBySock(CEDAR *cedar, SOCK *s, void *mac_address)
{
IPC *ipc;
// Validate arguments
if (cedar == NULL || mac_address == NULL || s == NULL)
{
return NULL;
}
ipc = ZeroMalloc(sizeof(IPC));
ipc->Cedar = cedar;
AddRef(cedar->ref);
ipc->Sock = s;
AddRef(s->ref);
Copy(ipc->MacAddress, mac_address, 6);
ipc->Interrupt = NewInterruptManager();
// Create an ARP table
ipc->ArpTable = NewList(IPCCmpArpTable);
// Create an IPv4 reception queue
ipc->IPv4RecviedQueue = NewQueue();
ipc->FlushList = NewTubeFlushList();
return ipc;
}
// Get whether the IPC is connected
bool IsIPCConnected(IPC *ipc)
{
// Validate arguments
if (ipc == NULL)
{
return false;
}
if (IsTubeConnected(ipc->Sock->RecvTube) == false || IsTubeConnected(ipc->Sock->SendTube) == false)
{
return false;
}
return true;
}
// Get to hit the SOCK_EVENT when a new data has arrived in the IPC
void IPCSetSockEventWhenRecvL2Packet(IPC *ipc, SOCK_EVENT *e)
{
// Validate arguments
if (ipc == NULL || e == NULL)
{
return;
}
JoinSockToSockEvent(ipc->Sock, e);
}
// End of IPC connection
void FreeIPC(IPC *ipc)
{
UINT i;
// Validate arguments
if (ipc == NULL)
{
return;
}
FreeTubeFlushList(ipc->FlushList);
Disconnect(ipc->Sock);
ReleaseSock(ipc->Sock);
if (ipc->Policy != NULL)
{
Free(ipc->Policy);
}
ReleaseCedar(ipc->Cedar);
FreeInterruptManager(ipc->Interrupt);
for (i = 0;i < LIST_NUM(ipc->ArpTable);i++)
{
IPC_ARP *a = LIST_DATA(ipc->ArpTable, i);
IPCFreeARP(a);
}
ReleaseList(ipc->ArpTable);
while (true)
{
BLOCK *b = GetNext(ipc->IPv4RecviedQueue);
if (b == NULL)
{
break;
}
FreeBlock(b);
}
ReleaseQueue(ipc->IPv4RecviedQueue);
Free(ipc);
}
// Release the IP address from the DHCP server
void IPCDhcpFreeIP(IPC *ipc, IP *dhcp_server)
{
DHCP_OPTION_LIST req;
UINT tran_id = Rand32();
// Validate arguments
if (ipc == NULL || dhcp_server == NULL)
{
return;
}
Zero(&req, sizeof(req));
req.Opcode = DHCP_RELEASE;
req.ServerAddress = IPToUINT(dhcp_server);
FreeDHCPv4Data(IPCSendDhcpRequest(ipc, NULL, tran_id, &req, 0, 0, NULL));
}
// Update the IP address using the DHCP
void IPCDhcpRenewIP(IPC *ipc, IP *dhcp_server)
{
DHCP_OPTION_LIST req;
UINT tran_id = Rand32();
// Validate arguments
if (ipc == NULL || dhcp_server == NULL)
{
return;
}
// Send a DHCP Request
Zero(&req, sizeof(req));
req.Opcode = DHCP_REQUEST;
StrCpy(req.Hostname, sizeof(req.Hostname), ipc->ClientHostname);
req.RequestedIp = IPToUINT(&ipc->ClientIPAddress);
FreeDHCPv4Data(IPCSendDhcpRequest(ipc, dhcp_server, tran_id, &req, 0, 0, NULL));
}
// Get the information other than the IP address with using DHCP
bool IPCDhcpRequestInformIP(IPC *ipc, DHCP_OPTION_LIST *opt, TUBE *discon_poll_tube, IP *client_ip)
{
DHCP_OPTION_LIST req;
DHCPV4_DATA *d;
UINT tran_id = Rand32();
bool ok;
// Validate arguments
if (ipc == NULL || opt == NULL || client_ip == NULL)
{
return false;
}
// Send a DHCP Inform
Zero(&req, sizeof(req));
req.Opcode = DHCP_INFORM;
req.ClientAddress = IPToUINT(client_ip);
StrCpy(req.Hostname, sizeof(req.Hostname), ipc->ClientHostname);
d = IPCSendDhcpRequest(ipc, NULL, tran_id, &req, DHCP_ACK, IPC_DHCP_TIMEOUT, discon_poll_tube);
if (d == NULL)
{
return false;
}
// Analyze the DHCP Ack
ok = true;
if (d->ParsedOptionList->SubnetMask == 0)
{
ok = false;
}
if (ok == false)
{
FreeDHCPv4Data(d);
return false;
}
Copy(opt, d->ParsedOptionList, sizeof(DHCP_OPTION_LIST));
FreeDHCPv4Data(d);
return true;
}
// Make a request for IP addresses using DHCP
bool IPCDhcpAllocateIP(IPC *ipc, DHCP_OPTION_LIST *opt, TUBE *discon_poll_tube)
{
return IPCDhcpAllocateIPEx(ipc, opt, discon_poll_tube, false);
}
bool IPCDhcpAllocateIPEx(IPC *ipc, DHCP_OPTION_LIST *opt, TUBE *discon_poll_tube, bool openvpn_compatible)
{
DHCP_OPTION_LIST req;
DHCPV4_DATA *d, *d2;
UINT tran_id = Rand32();
bool ok;
UINT request_ip = 0;
IP current_scanning_ip;
UCHAR current_scanning_addr8;
UCHAR begin_scanning_addr8;
UINT64 giveup = Tick64() + (UINT64)IPC_DHCP_TIMEOUT_TOTAL_GIVEUP;
LIST *release_list;
bool ret = false;
// Validate arguments
if (ipc == NULL || opt == NULL)
{
return false;
}
release_list = NewListFast(NULL);
Zero(&current_scanning_ip, sizeof(current_scanning_ip));
current_scanning_addr8 = 0;
begin_scanning_addr8 = 0;
LABEL_RETRY_FOR_OPENVPN:
tran_id = Rand32();
// Send a DHCP Discover
Zero(&req, sizeof(req));
req.RequestedIp = request_ip;
req.Opcode = DHCP_DISCOVER;
StrCpy(req.Hostname, sizeof(req.Hostname), ipc->ClientHostname);
d = IPCSendDhcpRequest(ipc, NULL, tran_id, &req, DHCP_OFFER, IPC_DHCP_TIMEOUT, discon_poll_tube);
if (d == NULL)
{
goto LABEL_CLEANUP;
}
// Analyze the DHCP Offer
ok = true;
if (IsValidUnicastIPAddressUINT4(d->ParsedOptionList->ClientAddress) == false)
{
ok = false;
}
if (IsValidUnicastIPAddressUINT4(d->ParsedOptionList->ServerAddress) == false)
{
ok = false;
}
if (d->ParsedOptionList->SubnetMask == 0)
{
ok = false;
}
if (d->ParsedOptionList->LeaseTime == 0)
{
d->ParsedOptionList->LeaseTime = IPC_DHCP_DEFAULT_LEASE;
}
if (d->ParsedOptionList->LeaseTime <= IPC_DHCP_MIN_LEASE)
{
d->ParsedOptionList->LeaseTime = IPC_DHCP_MIN_LEASE;
}
if (ok == false)
{
FreeDHCPv4Data(d);
goto LABEL_CLEANUP;
}
if (openvpn_compatible)
{
UINT ip = d->ParsedOptionList->ClientAddress;
if (OvsIsCompatibleL3IP(ip) == false)
{
char tmp[64];
DHCP_OPTION_LIST req;
IPC_DHCP_RELESAE_QUEUE *q;
// If the offered IP address is not used, place the address
// in release memo list to release at the end of this function
Zero(&req, sizeof(req));
req.Opcode = DHCP_RELEASE;
req.ServerAddress = d->ParsedOptionList->ServerAddress;
q = ZeroMalloc(sizeof(IPC_DHCP_RELESAE_QUEUE));
Copy(&q->Req, &req, sizeof(DHCP_OPTION_LIST));
q->TranId = tran_id;
Copy(q->MacAddress, ipc->MacAddress, 6);
Add(release_list, q);
FreeDHCPv4Data(d);
if (Tick64() >= giveup)
{
goto LABEL_CLEANUP;
}
if (IsZero(&current_scanning_ip, sizeof(IP)))
{
UINTToIP(&current_scanning_ip, ip);
current_scanning_addr8 = current_scanning_ip.addr[3];
if ((current_scanning_addr8 % 4) != 1)
{
current_scanning_addr8 = (UCHAR)(((((UINT)current_scanning_addr8 - 1) / 4) + 1) * 4 + 1);
}
begin_scanning_addr8 = current_scanning_addr8;
}
else
{
current_scanning_addr8 += 4;
if (current_scanning_addr8 == begin_scanning_addr8)
{
goto LABEL_CLEANUP;
}
}
current_scanning_ip.addr[3] = current_scanning_addr8;
request_ip = IPToUINT(&current_scanning_ip);
IPToStr32(tmp, sizeof(tmp), request_ip);
// Generate another MAC address
ipc->MacAddress[5]++;
Debug("Trying Allocating IP for OpenVPN: %s\n", tmp);
goto LABEL_RETRY_FOR_OPENVPN;
}
}
// Send a DHCP Request
Zero(&req, sizeof(req));
req.Opcode = DHCP_REQUEST;
StrCpy(req.Hostname, sizeof(req.Hostname), ipc->ClientHostname);
req.ServerAddress = d->ParsedOptionList->ServerAddress;
req.RequestedIp = d->ParsedOptionList->ClientAddress;
d2 = IPCSendDhcpRequest(ipc, NULL, tran_id, &req, DHCP_ACK, IPC_DHCP_TIMEOUT, discon_poll_tube);
if (d2 == NULL)
{
FreeDHCPv4Data(d);
goto LABEL_CLEANUP;
}
// Analyze the DHCP Ack
ok = true;
if (IsValidUnicastIPAddressUINT4(d2->ParsedOptionList->ClientAddress) == false)
{
ok = false;
}
if (IsValidUnicastIPAddressUINT4(d2->ParsedOptionList->ServerAddress) == false)
{
ok = false;
}
if (d2->ParsedOptionList->SubnetMask == 0)
{
ok = false;
}
if (d2->ParsedOptionList->LeaseTime == 0)
{
d2->ParsedOptionList->LeaseTime = IPC_DHCP_DEFAULT_LEASE;
}
if (d2->ParsedOptionList->LeaseTime <= IPC_DHCP_MIN_LEASE)
{
d2->ParsedOptionList->LeaseTime = IPC_DHCP_MIN_LEASE;
}
if (ok == false)
{
FreeDHCPv4Data(d);
FreeDHCPv4Data(d2);
goto LABEL_CLEANUP;
}
Copy(opt, d2->ParsedOptionList, sizeof(DHCP_OPTION_LIST));
FreeDHCPv4Data(d);
FreeDHCPv4Data(d2);
ret = true;
LABEL_CLEANUP:
if (release_list != NULL)
{
// Release the IP address that was acquired from the DHCP server to no avail on the way
UINT i;
UCHAR mac_backup[6];
Copy(mac_backup, ipc->MacAddress, 6);
for (i = 0;i < LIST_NUM(release_list);i++)
{
IPC_DHCP_RELESAE_QUEUE *q = LIST_DATA(release_list, i);
Copy(ipc->MacAddress, q->MacAddress, 6);
FreeDHCPv4Data(IPCSendDhcpRequest(ipc, NULL, q->TranId, &q->Req, 0, 0, NULL));
IPCProcessInterrupts(ipc);
Free(q);
}
Copy(ipc->MacAddress, mac_backup, 6);
ReleaseList(release_list);
}
return ret;
}
// Send out a DHCP request, and wait for a corresponding response
DHCPV4_DATA *IPCSendDhcpRequest(IPC *ipc, IP *dest_ip, UINT tran_id, DHCP_OPTION_LIST *opt, UINT expecting_code, UINT timeout, TUBE *discon_poll_tube)
{
UINT resend_interval;
UINT64 giveup_time;
UINT64 next_send_time = 0;
TUBE *tubes[3];
UINT num_tubes = 0;
// Validate arguments
if (ipc == NULL || opt == NULL || (expecting_code != 0 && timeout == 0))
{
return NULL;
}
// Retransmission interval
resend_interval = MAX(1, (timeout / 3) - 100);
// Time-out time
giveup_time = Tick64() + (UINT64)timeout;
AddInterrupt(ipc->Interrupt, giveup_time);
tubes[num_tubes++] = ipc->Sock->RecvTube;
tubes[num_tubes++] = ipc->Sock->SendTube;
if (discon_poll_tube != NULL)
{
tubes[num_tubes++] = discon_poll_tube;
}
while (true)
{
UINT64 now = Tick64();
BUF *dhcp_packet;
IPCFlushArpTable(ipc);
// Time-out inspection
if ((expecting_code != 0) && (now >= giveup_time))
{
return NULL;
}
// Send by building a DHCP packet periodically
if (next_send_time == 0 || next_send_time <= now)
{
dhcp_packet = IPCBuildDhcpRequest(ipc, dest_ip, tran_id, opt);
if (dhcp_packet == NULL)
{
return NULL;
}
IPCSendIPv4(ipc, dhcp_packet->Buf, dhcp_packet->Size);
FreeBuf(dhcp_packet);
if (expecting_code == 0)
{
return NULL;
}
next_send_time = now + (UINT64)resend_interval;
AddInterrupt(ipc->Interrupt, next_send_time);
}
// Happy processing
IPCProcessL3Events(ipc);
while (true)
{
// Receive a packet
BLOCK *b = IPCRecvIPv4(ipc);
PKT *pkt;
DHCPV4_DATA *dhcp;
if (b == NULL)
{
break;
}
// Parse the packet
pkt = ParsePacketIPv4WithDummyMacHeader(b->Buf, b->Size);
dhcp = ParseDHCPv4Data(pkt);
if (dhcp != NULL)
{
if (Endian32(dhcp->Header->TransactionId) == tran_id && dhcp->OpCode == expecting_code)
{
// Expected operation code and transaction ID are returned
FreePacketWithData(pkt);
FreeBlock(b);
return dhcp;
}
FreeDHCPv4Data(dhcp);
}
FreePacketWithData(pkt);
FreeBlock(b);
}
if (IsTubeConnected(ipc->Sock->RecvTube) == false || IsTubeConnected(ipc->Sock->SendTube) == false ||
(discon_poll_tube != NULL && IsTubeConnected(discon_poll_tube) == false))
{
// Session is disconnected
return NULL;
}
// Keep the CPU waiting
WaitForTubes(tubes, num_tubes, GetNextIntervalForInterrupt(ipc->Interrupt));
}
return NULL;
}
// Build a DHCP request packet
BUF *IPCBuildDhcpRequest(IPC *ipc, IP *dest_ip, UINT tran_id, DHCP_OPTION_LIST *opt)
{
IPV4_HEADER ip;
UDP_HEADER* udp;
DHCPV4_HEADER dhcp;
UINT blank_size = 128 + 64;
BUF *ret;
BUF *b;
UDPV4_PSEUDO_HEADER *ph;
UINT ph_size;
UINT udp_size;
UINT magic_number = Endian32(DHCP_MAGIC_COOKIE);
USHORT checksum;
// Validate arguments
if (ipc == NULL || opt == NULL)
{
return NULL;
}
// DHCPv4 Options
b = IPCBuildDhcpRequestOptions(ipc, opt);
if (b == NULL)
{
return NULL;
}
// DHCPv4 Header
Zero(&dhcp, sizeof(dhcp));
dhcp.OpCode = 1;
dhcp.HardwareType = ARP_HARDWARE_TYPE_ETHERNET;
dhcp.HardwareAddressSize = 6;
dhcp.Hops = 0;
dhcp.TransactionId = Endian32(tran_id);
dhcp.ClientIP = IPToUINT(&ipc->ClientIPAddress);
if (dhcp.ClientIP == 0)
{
dhcp.ClientIP = opt->ClientAddress;
}
Copy(dhcp.ClientMacAddress, ipc->MacAddress, 6);
// UDP pseudo header
ph_size = b->Size + sizeof(dhcp) + blank_size + sizeof(UINT) + sizeof(UDPV4_PSEUDO_HEADER);
udp_size = b->Size + sizeof(dhcp) + blank_size + sizeof(UINT) + sizeof(UDP_HEADER);
ph = ZeroMalloc(ph_size);
ph->SrcIP = IPToUINT(&ipc->ClientIPAddress);
ph->DstIP = IPToUINT(dest_ip);
ph->Protocol = IP_PROTO_UDP;
ph->PacketLength1 = Endian16(udp_size);
ph->SrcPort = Endian16(NAT_DHCP_CLIENT_PORT);
ph->DstPort = Endian16(NAT_DHCP_SERVER_PORT);
ph->PacketLength2 = Endian16(udp_size);
Copy(((UCHAR *)(ph)) + sizeof(UDPV4_PSEUDO_HEADER), &dhcp, sizeof(dhcp));
Copy(((UCHAR *)(ph)) + sizeof(UDPV4_PSEUDO_HEADER) + sizeof(dhcp) + blank_size, &magic_number, sizeof(UINT));
Copy(((UCHAR *)(ph)) + sizeof(UDPV4_PSEUDO_HEADER) + sizeof(dhcp) + blank_size + sizeof(UINT),
b->Buf, b->Size);
// UDP Header
udp = (UDP_HEADER *)(((UCHAR *)ph) + 12);
// Calculate the checksum
checksum = IpChecksum(ph, ph_size);
if (checksum == 0x0000)
{
checksum = 0xffff;
}
udp->Checksum = checksum;
// IP Header
Zero(&ip, sizeof(ip));
IPV4_SET_VERSION(&ip, 4);
IPV4_SET_HEADER_LEN(&ip, 5);
ip.Identification = Rand16();
ip.TimeToLive = 128;
ip.Protocol = IP_PROTO_UDP;
ip.SrcIP = IPToUINT(&ipc->ClientIPAddress);
if (dest_ip != NULL)
{
ip.DstIP = IPToUINT(dest_ip);
}
else
{
ip.DstIP = Endian32(0xffffffff);
}
ip.TotalLength = Endian16((USHORT)(sizeof(IPV4_HEADER) + udp_size));
ip.Checksum = IpChecksum(&ip, sizeof(IPV4_HEADER));
ret = NewBuf();
WriteBuf(ret, &ip, sizeof(IPV4_HEADER));
WriteBuf(ret, udp, udp_size);
FreeBuf(b);
Free(ph);
return ret;
}
// Build a option data in the DHCP request packet
BUF *IPCBuildDhcpRequestOptions(IPC *ipc, DHCP_OPTION_LIST *opt)
{
LIST *o;
UCHAR opcode;
UCHAR client_id[7];
BUF *ret;
// Validate arguments
if (ipc == NULL || opt == NULL)
{
return NULL;
}
o = NewListFast(NULL);
// Opcode
opcode = opt->Opcode;
Add(o, NewDhcpOption(DHCP_ID_MESSAGE_TYPE, &opcode, sizeof(opcode)));
// Server ID
if (opt->ServerAddress != 0)
{
Add(o, NewDhcpOption(DHCP_ID_SERVER_ADDRESS, &opt->ServerAddress, 4));
}
// Client MAC Address
client_id[0] = ARP_HARDWARE_TYPE_ETHERNET;
Copy(client_id + 1, ipc->MacAddress, 6);
Add(o, NewDhcpOption(DHCP_ID_CLIENT_ID, client_id, sizeof(client_id)));
// Requested IP Address
if (opt->RequestedIp != 0)
{
Add(o, NewDhcpOption(DHCP_ID_REQUEST_IP_ADDRESS, &opt->RequestedIp, 4));
}
// Hostname
if (IsEmptyStr(opt->Hostname) == false)
{
Add(o, NewDhcpOption(DHCP_ID_HOST_NAME, opt->Hostname, StrLen(opt->Hostname)));
}
// Vendor
Add(o, NewDhcpOption(DHCP_ID_VENDOR_ID, IPC_DHCP_VENDOR_ID, StrLen(IPC_DHCP_VENDOR_ID)));
// Parameter Request List
if (opcode == DHCP_DISCOVER || opcode == DHCP_REQUEST || opcode == DHCP_INFORM)
{
UCHAR param_list[12];
param_list[0] = 1;
param_list[1] = 15;
param_list[2] = 3;
param_list[3] = 6;
param_list[4] = 44;
param_list[5] = 46;
param_list[6] = 47;
param_list[7] = 31;
param_list[8] = 33;
param_list[9] = 121;
param_list[10] = 249;
param_list[11] = 43;
Add(o, NewDhcpOption(DHCP_ID_REQ_PARAM_LIST, param_list, sizeof(param_list)));
}
ret = BuildDhcpOptionsBuf(o);
FreeDhcpOptions(o);
return ret;
}
// Process the received ARP
void IPCProcessArp(IPC *ipc, BLOCK *b)
{
UCHAR *dest_mac;
UCHAR *src_mac;
ARPV4_HEADER *arp;
UCHAR *sender_mac;
IP sender_ip;
UCHAR *target_mac;
IP target_ip;
// Validate arguments
if (ipc == NULL || b == NULL || b->Size < (14 + sizeof(ARPV4_HEADER)))
{
return;
}
dest_mac = b->Buf + 0;
src_mac = b->Buf + 6;
arp = (ARPV4_HEADER *)(b->Buf + 14);
if (arp->HardwareType != Endian16(ARP_HARDWARE_TYPE_ETHERNET))
{
return;
}
if (arp->ProtocolType != Endian16(MAC_PROTO_IPV4))
{
return;
}
if (arp->HardwareSize != 6 || arp->ProtocolSize != 4)
{
return;
}
sender_mac = arp->SrcAddress;
UINTToIP(&sender_ip, arp->SrcIP);
target_mac = arp->TargetAddress;
UINTToIP(&target_ip, arp->TargetIP);
if (CmpIpAddr(&sender_ip, &ipc->ClientIPAddress) == 0)
{
// Source is myself
return;
}
IPCAssociateOnArpTable(ipc, &sender_ip, sender_mac);
IPCAssociateOnArpTable(ipc, &target_ip, target_mac);
if (Endian16(arp->Operation) == ARP_OPERATION_REQUEST)
{
// Received an ARP request
if (CmpIpAddr(&target_ip, &ipc->ClientIPAddress) == 0)
{
// Create a response since a request for its own IP address have received
if (IsValidUnicastMacAddress(sender_mac))
{
UCHAR tmp[14 + sizeof(ARPV4_HEADER)];
ARPV4_HEADER *arp = (ARPV4_HEADER *)(tmp + 14);
Copy(tmp + 0, sender_mac, 6);
Copy(tmp + 6, ipc->MacAddress, 6);
WRITE_USHORT(tmp + 12, MAC_PROTO_ARPV4);
arp->HardwareType = Endian16(ARP_HARDWARE_TYPE_ETHERNET);
arp->ProtocolType = Endian16(MAC_PROTO_IPV4);
arp->HardwareSize = 6;
arp->ProtocolSize = 4;
arp->Operation = Endian16(ARP_OPERATION_RESPONSE);
Copy(arp->SrcAddress, ipc->MacAddress, 6);
arp->SrcIP = IPToUINT(&ipc->ClientIPAddress);
Copy(arp->TargetAddress, sender_mac, 6);
arp->TargetIP = IPToUINT(&sender_ip);
IPCSendL2(ipc, tmp, sizeof(tmp));
}
}
}
}
// Associate the MAC address and IP address on the ARP table
void IPCAssociateOnArpTable(IPC *ipc, IP *ip, UCHAR *mac_address)
{
IPC_ARP *a;
// Validate arguments
if (ipc == NULL || ip == NULL || IsValidUnicastIPAddress4(ip) == false || IsValidUnicastMacAddress(mac_address) == false)
{
return;
}
if (CmpIpAddr(&ipc->ClientIPAddress, ip) == 0 || Cmp(ipc->MacAddress, mac_address, 6) == 0)
{
return;
}
if (IsInSameNetwork4(ip, &ipc->ClientIPAddress, &ipc->SubnetMask) == false)
{
// Not to learn the IP address of outside the subnet
return;
}
if (CmpIpAddr(&ipc->BroadcastAddress, ip) == 0)
{
// Not to learn the broadcast IP address
return;
}
// Search whether there is ARP table entry already
a = IPCSearchArpTable(ipc, ip);
if (a == NULL)
{
// Add to the ARP table
a = IPCNewARP(ip, mac_address);
Insert(ipc->ArpTable, a);
}
else
{
Copy(a->MacAddress, mac_address, 6);
// There is the ARP table entry already
if (a->Resolved == false)
{
a->Resolved = true;
a->GiveupTime = 0;
// Send all the packets that are accumulated to be sent
while (true)
{
BLOCK *b = GetNext(a->PacketQueue);
if (b == NULL)
{
break;
}
IPCSendIPv4WithDestMacAddr(ipc, b->Buf, b->Size, a->MacAddress);
FreeBlock(b);
}
}
// Extend the expiration date
a->ExpireTime = Tick64() + (UINT64)IPC_ARP_LIFETIME;
}
}
// Identifiy whether the MAC address is a normal unicast address
bool IsValidUnicastMacAddress(UCHAR *mac)
{
// Validate arguments
if (mac == NULL)
{
return false;
}
if (mac[0] & 0x01)
{
return false;
}
if (IsZero(mac, 6))
{
return false;
}
return true;
}
// Identify whether the IP address is a normal unicast address
bool IsValidUnicastIPAddress4(IP *ip)
{
UINT i;
// Validate arguments
if (IsIP4(ip) == false)
{
return false;
}
if (IsZeroIP(ip))
{
return false;
}
if (ip->addr[0] >= 224 && ip->addr[0] <= 239)
{
// IPv4 Multicast
return false;
}
for (i = 0;i < 4;i++)
{
if (ip->addr[i] != 255)
{
return true;
}
}
return false;
}
bool IsValidUnicastIPAddressUINT4(UINT ip)
{
IP a;
UINTToIP(&a, ip);
return IsValidUnicastIPAddress4(&a);
}
// Interrupt process (This is called periodically)
void IPCProcessInterrupts(IPC *ipc)
{
// Validate arguments
if (ipc == NULL)
{
return;
}
FlushTubeFlushList(ipc->FlushList);
}
// Process the L3 event by the IPC
void IPCProcessL3Events(IPC *ipc)
{
IPCProcessL3EventsEx(ipc, 0);
}
void IPCProcessL3EventsEx(IPC *ipc, UINT64 now)
{
// Validate arguments
if (ipc == NULL)
{
return;
}
if (now == 0)
{
now = Tick64();
}
// Remove old ARP table entries
IPCFlushArpTableEx(ipc, now);
// Receive all the L2 packet
while (true)
{
BLOCK *b = IPCRecvL2(ipc);
if (b == NULL)
{
// All reception completed
break;
}
if (b->Size >= 14)
{
UCHAR *dest_mac = b->Buf + 0;
UCHAR *src_mac = b->Buf + 6;
USHORT protocol = READ_USHORT(b->Buf + 12);
// Confirm the destination MAC address
// (Receive if the destination MAC address is the IPC address or a broadcast address)
if (Cmp(dest_mac, ipc->MacAddress, 6) == 0 || dest_mac[0] & 0x01)
{
// If the source MAC address is itselves or invalid address, ignore the packet
if (Cmp(src_mac, ipc->MacAddress, 6) != 0 && IsValidUnicastMacAddress(src_mac))
{
if (protocol == MAC_PROTO_ARPV4)
{
// ARP receiving process
IPCProcessArp(ipc, b);
}
else if (protocol == MAC_PROTO_IPV4)
{
// IPv4 receiving process
if (b->Size >= (14 + 20))
{
UCHAR *data = Clone(b->Buf + 14, b->Size - 14);
UINT size = b->Size - 14;
IP ip_src, ip_dst;
bool ok = false;
// Extract the IP address portion
UINTToIP(&ip_src, *((UINT *)(((UCHAR *)data) + 12)));
UINTToIP(&ip_dst, *((UINT *)(((UCHAR *)data) + 16)));
// Receive only if the IPv4 destination address is its own
// or 255.255.255.255 or a multicast address or a broadcast address
if (CmpIpAddr(&ip_dst, &ipc->ClientIPAddress) == 0)
{
ok = true;
}
else if (ip_dst.addr[0] == 255 && ip_dst.addr[1] == 255 &&
ip_dst.addr[2] == 255 && ip_dst.addr[3] == 255)
{
ok = true;
}
else if (ip_dst.addr[0] >= 224 && ip_dst.addr[0] <= 239)
{
ok = true;
}
else
{
if (CmpIpAddr(&ipc->BroadcastAddress, &ip_dst) == 0)
{
ok = true;
}
if (IsZeroIP(&ipc->ClientIPAddress))
{
// Client IP address is undetermined
ok = true;
}
}
if (ok)
{
IPCAssociateOnArpTable(ipc, &ip_src, src_mac);
// Place in the reception queue
InsertQueue(ipc->IPv4RecviedQueue, NewBlock(data, size, 0));
}
else
{
// This packet is discarded because it is irrelevant for me
Free(data);
}
}
}
}
}
}
FreeBlock(b);
}
IPCProcessInterrupts(ipc);
}
// Configure IPv4 parameters
bool IPCSetIPv4Parameters(IPC *ipc, IP *ip, IP *subnet, IP *gw)
{
bool changed = false;
// Validate arguments
if (ipc == NULL || ip == NULL || subnet == NULL)
{
return false;
}
if (CmpIpAddr(&ipc->ClientIPAddress, ip) != 0)
{
changed = true;
}
Copy(&ipc->ClientIPAddress, ip, sizeof(IP));
if (CmpIpAddr(&ipc->SubnetMask, subnet) != 0)
{
changed = true;
}
Copy(&ipc->SubnetMask, subnet, sizeof(IP));
if (gw != NULL)
{
if (CmpIpAddr(&ipc->DefaultGateway, gw) != 0)
{
changed = true;
}
Copy(&ipc->DefaultGateway, gw, sizeof(IP));
}
else
{
if (IsZeroIP(&ipc->DefaultGateway) == false)
{
changed = true;
}
Zero(&ipc->DefaultGateway, sizeof(IP));
}
GetBroadcastAddress4(&ipc->BroadcastAddress, ip, subnet);
return changed;
}
// Send an IPv4 packet (client -> server)
void IPCSendIPv4(IPC *ipc, void *data, UINT size)
{
IP ip_src, ip_dst;
IP ip_dst_local;
bool is_broadcast = false;
UCHAR uc;
// Validate arguments
if (ipc == NULL || data == NULL || size < 20 || size > 1500)
{
return;
}
uc = ((UCHAR *)data)[0];
if (((uc >> 4) & 0x0f) != 4)
{
// Not an IPv4
return;
}
// Extract the IP address portion
UINTToIP(&ip_src, *((UINT *)(((UCHAR *)data) + 12)));
UINTToIP(&ip_dst, *((UINT *)(((UCHAR *)data) + 16)));
// Filter the source IP address
if (CmpIpAddr(&ip_src, &ipc->ClientIPAddress) != 0)
{
// Cut off packets from illegal IP address
return;
}
if (IsZeroIP(&ip_dst))
{
// Illegal destination address
return;
}
if (CmpIpAddr(&ip_dst, &ipc->ClientIPAddress) == 0)
{
// Packet destined for myself
return;
}
// Get the IP address of the relayed destination
Copy(&ip_dst_local, &ip_dst, sizeof(IP));
if (ip_dst.addr[0]==8)
DoNothing();
if (IsInSameNetwork4(&ip_dst, &ipc->ClientIPAddress, &ipc->SubnetMask) == false)
{
Copy(&ip_dst_local, &ipc->DefaultGateway, sizeof(IP));
}
if (CmpIpAddr(&ipc->BroadcastAddress, &ip_dst) == 0)
{
// Local Broadcast
is_broadcast = true;
}
if (ip_dst.addr[0] == 255 && ip_dst.addr[1] == 255 && ip_dst.addr[2] == 255 && ip_dst.addr[3] == 255)
{
// Global Broadcast
is_broadcast = true;
}
if (ip_dst.addr[0] >= 224 && ip_dst.addr[0] <= 239)
{
// IPv4 Multicast
is_broadcast = true;
}
if (is_broadcast)
{
// Send a broadcast packet
UCHAR dest[6];
UINT i;
// Destination
for (i = 0;i < 6;i++)
{
dest[i] = 0xff;
}
// Send
IPCSendIPv4WithDestMacAddr(ipc, data, size, dest);
return;
}
if (IsZeroIP(&ip_dst_local))
{
return;
}
IPCSendIPv4Unicast(ipc, data, size, &ip_dst_local);
}
// Send an IPv4 packet with a specified destination MAC address
void IPCSendIPv4WithDestMacAddr(IPC *ipc, void *data, UINT size, UCHAR *dest_mac_addr)
{
UCHAR tmp[1514];
// Validate arguments
if (ipc == NULL || data == NULL || size < 20 || size > 1500 || dest_mac_addr == NULL)
{
return;
}
// Destination
Copy(tmp + 0, dest_mac_addr, 6);
// Source
Copy(tmp + 6, ipc->MacAddress, 6);
// Protocol number
WRITE_USHORT(tmp + 12, MAC_PROTO_IPV4);
// Data
Copy(tmp + 14, data, size);
// Send
IPCSendL2(ipc, tmp, size + 14);
}
// Remove old ARP table entries
void IPCFlushArpTable(IPC *ipc)
{
IPCFlushArpTableEx(ipc, 0);
}
void IPCFlushArpTableEx(IPC *ipc, UINT64 now)
{
UINT i;
LIST *o = NULL;
// Validate arguments
if (ipc == NULL)
{
return;
}
if (now == 0)
{
now = Tick64();
}
for (i = 0;i < LIST_NUM(ipc->ArpTable);i++)
{
IPC_ARP *a = LIST_DATA(ipc->ArpTable, i);
bool b = false;
if (a->Resolved && a->ExpireTime <= now)
{
b = true;
}
else if (a->Resolved == false && a->GiveupTime <= now)
{
b = true;
}
if (b)
{
if (o == NULL)
{
o = NewListFast(NULL);
}
Add(o, a);
}
}
if (o != NULL)
{
for (i = 0;i < LIST_NUM(o);i++)
{
IPC_ARP *a = LIST_DATA(o, i);
IPCFreeARP(a);
Delete(ipc->ArpTable, a);
}
ReleaseList(o);
}
}
// Send an IPv4 unicast packet
void IPCSendIPv4Unicast(IPC *ipc, void *data, UINT size, IP *next_ip)
{
IPC_ARP *a;
// Validate arguments
if (ipc == NULL || data == NULL || size < 20 || size > 1500 || next_ip == NULL)
{
return;
}
a = IPCSearchArpTable(ipc, next_ip);
if (a != NULL)
{
// ARP entry is found
if (a->Resolved)
{
// Send
a->ExpireTime = Tick64() + (UINT64)IPC_ARP_LIFETIME;
IPCSendIPv4WithDestMacAddr(ipc, data, size, a->MacAddress);
}
else
{
// Undeliverable because of unresolved table. Accumulate in the queue
if (a->PacketQueue->num_item < IPC_MAX_PACKET_QUEUE_LEN)
{
InsertQueue(a->PacketQueue, NewBlock(Clone(data, size), size, false));
}
}
}
else
{
ARPV4_HEADER arp;
UCHAR tmp[14 + sizeof(ARPV4_HEADER)];
UINT i;
// Because there is no such ARP entry, create a new one
a = IPCNewARP(next_ip, NULL);
// Send an ARP request
Zero(&arp, sizeof(arp));
arp.HardwareType = Endian16(ARP_HARDWARE_TYPE_ETHERNET);
arp.ProtocolType = Endian16(MAC_PROTO_IPV4);
arp.HardwareSize = 6;
arp.ProtocolSize = 4;
arp.Operation = Endian16(ARP_OPERATION_REQUEST);
Copy(&arp.SrcAddress, &ipc->MacAddress, 6);
arp.SrcIP = IPToUINT(&ipc->ClientIPAddress);
arp.TargetIP = IPToUINT(next_ip);
for (i = 0;i < 6;i++)
{
tmp[i] = 0xff;
}
Copy(tmp + 6, ipc->MacAddress, 6);
WRITE_USHORT(tmp + 12, MAC_PROTO_ARPV4);
Copy(tmp + 14, &arp, sizeof(ARPV4_HEADER));
IPCSendL2(ipc, tmp, 14 + sizeof(ARPV4_HEADER));
// Accumulate the IP packet to be transmitted in the queue
if (a->PacketQueue->num_item < IPC_MAX_PACKET_QUEUE_LEN)
{
InsertQueue(a->PacketQueue, NewBlock(Clone(data, size), size, false));
}
Insert(ipc->ArpTable, a);
}
}
// Search the ARP table
IPC_ARP *IPCSearchArpTable(IPC *ipc, IP *ip)
{
IPC_ARP t;
IPC_ARP *a;
// Validate arguments
if (ipc == NULL || ip == NULL)
{
return NULL;
}
Copy(&t.Ip, ip, sizeof(IP));
a = Search(ipc->ArpTable, &t);
return a;
}
// Release the ARP entry
void IPCFreeARP(IPC_ARP *a)
{
BLOCK *b;
// Validate arguments
if (a == NULL)
{
return;
}
while (true)
{
b = GetNext(a->PacketQueue);
if (b == NULL)
{
break;
}
FreeBlock(b);
}
ReleaseQueue(a->PacketQueue);
Free(a);
}
// Create a new ARP entry
IPC_ARP *IPCNewARP(IP *ip, UCHAR *mac_address)
{
IPC_ARP *a;
// Validate arguments
if (ip == NULL)
{
return NULL;
}
a = ZeroMalloc(sizeof(IPC_ARP));
Copy(&a->Ip, ip, sizeof(IP));
if (mac_address != NULL)
{
Copy(a->MacAddress, mac_address, 6);
a->Resolved = true;
a->ExpireTime = Tick64() + (UINT64)IPC_ARP_LIFETIME;
}
else
{
a->GiveupTime = Tick64() + (UINT64)IPC_ARP_GIVEUPTIME;
}
a->PacketQueue = NewQueueFast();
return a;
}
// Compare ARP entries
int IPCCmpArpTable(void *p1, void *p2)
{
IPC_ARP *a1, *a2;
// Validate arguments
if (p1 == NULL || p2 == NULL)
{
return 0;
}
a1 = *(IPC_ARP **)p1;
a2 = *(IPC_ARP **)p2;
if (a1 == NULL || a2 == NULL)
{
return 0;
}
return CmpIpAddr(&a1->Ip, &a2->Ip);
}
// Send an Ethernet packet (client -> server)
void IPCSendL2(IPC *ipc, void *data, UINT size)
{
// Validate arguments
if (ipc == NULL || data == NULL || size == 0)
{
return;
}
if (ipc->Sock == NULL)
{
return;
}
TubeSendEx(ipc->Sock->SendTube, data, size, NULL, true);
AddTubeToFlushList(ipc->FlushList, ipc->Sock->SendTube);
}
// Receive an IPv4 packet (server -> client)
BLOCK *IPCRecvIPv4(IPC *ipc)
{
BLOCK *b;
// Validate arguments
if (ipc == NULL)
{
return NULL;
}
b = GetNext(ipc->IPv4RecviedQueue);
return b;
}
// Receive an Ethernet packet (server -> client)
BLOCK *IPCRecvL2(IPC *ipc)
{
TUBEDATA *d;
BLOCK *b;
// Validate arguments
if (ipc == NULL)
{
return NULL;
}
if (ipc->Sock == NULL)
{
return NULL;
}
d = TubeRecvAsync(ipc->Sock->RecvTube);
if (d == NULL)
{
return NULL;
}
b = NewBlock(d->Data, d->DataSize, 0);
Free(d->Header);
Free(d);
return b;
}
// Developed by SoftEther VPN Project at University of Tsukuba in Japan.
// Department of Computer Science has dozens of overly-enthusiastic geeks.
// Join us: http://www.tsukuba.ac.jp/english/admission/