[收藏]穿透代理服务器编程

天云上人

  作者 allfresh
文章原始出处 www.allfresh.net/program/proxy.htm
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2 A* \# |' h: v1 N) ]3 T正文
% y7 ^6 Y+ n8 K6 f: _8 G0 m在网络程序设计过程中，我们经常要与各种类型的代理服务器打交道，比如在企业内部网通过代理去访问Internet网上的服务器等等，一般代理服务器支持几种常见的代理协议标准，如Socks4,Socks5,Http代理，其中Socks5需要用户验证，代理相对复杂。我在查阅RFC文档和相关资料后，特总结一些TCP协议穿透代理服务器的程序片断，希望对大家有所帮助。
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4 {$ [& f9 b; T" J/ M4 a/ K//使用到的结构
) X/ I$ e$ m( O( z  V* astruct sock4req1
  |- l3 b( {  D9 W8 w{
char VN;
; m5 ?% i# j9 a7 t( T9 R' fchar CD;
- ?9 @7 W: n. I/ iunsigned short Port;
9 ?# ^+ O' l  I$ d+ U  Zunsigned long IPAddr;
4 s# c* o, P& a4 }. Rchar other[1];
3 d, [2 O1 @3 R  w, k};
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struct sock4ans1
{
char VN;
; n, U  c7 r  t8 Kchar CD;
};
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' {: |: [1 Z* ?& f6 U0 Pstruct sock5req1
{
# @3 E, V7 }# ], A! x, U  `6 l' Uchar Ver;
) C  y& b& H9 A, b6 o3 X, F* Uchar nMethods;
char Methods[255];
: u; Z7 a  d. a};
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struct sock5ans1
0 _0 V  }0 N, L+ k) \- W' U+ m2 u{
char Ver;
char Method;
6 {& f2 J- a3 a' r% y: R7 e};
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. c5 f- X  c' a& I' Z+ v- |& Lstruct sock5req2
, j1 L" F* p9 z9 F, q5 X* h4 V{
0 @7 r: G# j' _char Ver;
char Cmd;
char Rsv;
9 |: h* x- X% U# D( S- p% gchar Atyp;
char other[1];
};
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8 a2 @3 {: t& i6 mstruct sock5ans2
; ]9 Q: \* ]( u7 _# h; }+ T) Y& R{
, P. e* J- h% N0 k2 }2 k  zchar Ver;
1 x- W$ G2 `5 b+ @+ ^. K2 Q4 R; Zchar Rep;
% d; ~+ @3 X# M0 r; M; `9 [char Rsv;
char Atyp;
5 h& }# g5 W) Y9 f, P$ T4 m& Echar other[1];
};
+ j9 G, D8 w- s' F# R1 Z/ _5 cwwww.chin aitpower.comJZM2iofLWRmFIxU68q4I3qxHU
struct authreq
/ G# i* Y0 j! a% k9 L, P  o{
char Ver;
1 H$ o* m# i) R% n' K) b; V0 F4 d7 echar Ulen;
' M& ^3 B8 x$ P. G$ Dchar Name[255];
char PLen;
char Pass[255];
  n6 \" I, P7 S. n};
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struct authans
' O- c$ @! D: T0 k; ?& S0 D+ Z{
1 o, G3 k/ Z' ]5 w/ F* kchar Ver;
char Status;
% F% R' G4 L. E5 R* T0 v; r  P) c};
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//通过Socks4方式代理
if( !ClientSock.Connect( g_ProxyInfo.m_strProxyIP,g_ProxyInfo.m_nProxyPort) )
. R: x/ `5 H  Q# o. T+ W% P{
* C+ c5 I& G; x0 `  Ym_sError = _T("不能连接到代理服务器!");
% L' H0 S# |4 {: D" H$ MClientSock.Close();
return FALSE;
( o) }5 u! B6 [7 q+ D* K}
. H6 s! p$ |- y6 dchar buff[100];
memset(buff,0,100);
struct sock4req1 *m_proxyreq;
m_proxyreq = (struct sock4req1 *)buff;
" }5 G7 k+ Z3 l. @4 jm_proxyreq->VN = 4;
9 |1 f9 h4 @# K; N0 U% Dm_proxyreq->CD = 1;
m_proxyreq-&gtort = ntohs(GetPort());
m_proxyreq->IPAddr = inet_addr(GetServerHostName());
ClientSock.Send(buff,9);
struct sock4ans1 *m_proxyans;
8 Y2 C' y/ n" x: r# |+ p1 K6 p- Em_proxyans = (struct sock4ans1 *)buff;
memset(buff,0,100);
ClientSock.Receive(buff,100);
: m( @3 V( N" lif(m_proxyans->VN != 0 || m_proxyans->CD != 90)
{
m_sError = _T("通过代理连接主站不成功!");
% Q  D; N: R9 R& F0 EClientSock.Close();
: u9 m8 v* P/ f. I/ u5 b' m% g3 jreturn FALSE;
5 Q' O" @4 d  t, z/ ?}
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6 t4 Q- q* @' u% C- I
* D, B4 N9 |; G; r//通过Socks5方式代理
  z4 G# _8 c3 mif( !ClientSock.Connect( g_ProxyInfo.m_strProxyIP,g_ProxyInfo.m_nProxyPort) )
! b+ p8 {! V/ v9 K/ B! W, ^{
m_sError = _T("不能连接到代理服务器!");
ClientSock.Close();
- M+ B3 g( C; w( E* k- i" Ereturn FALSE;
* ^4 t' @6 g" s; h) I+ @0 X0 F}
char buff[600];
$ Q% K2 `& x" D+ f% Q/ H0 \struct sock5req1 *m_proxyreq1;
m_proxyreq1 = (struct sock5req1 *)buff;
, F+ y% c5 g1 c9 _m_proxyreq1->Ver = 5;
8 p7 p; [+ v  i' y6 gm_proxyreq1->nMethods = 2;
m_proxyreq1->Methods[0] = 0;
7 y5 h$ a/ R" Q4 e# Y0 cm_proxyreq1->Methods[1] = 2;
ClientSock.Send(buff,4);
- w$ \8 S" E5 Y- H$ p3 v6 Bstruct sock5ans1 *m_proxyans1;
; Y$ z. T  a7 i7 \2 a" A$ R' b6 h% jm_proxyans1 = (struct sock5ans1 *)buff;
1 l7 M# J2 ]- ^- ~: `% omemset(buff,0,600);
ClientSock.Receive(buff,600);
if(m_proxyans1->Ver != 5 || (m_proxyans1->Method!=0 && m_proxyans1->Method!=2))
6 ^3 }. ?% R0 x- q3 `{
1 i  _$ i( r1 ?5 W6 S- ^m_sError = _T("通过代理连接主站不成功!");
ClientSock.Close();
9 s3 `1 J0 B% n% O5 u2 p8 ^return FALSE;
}
if(m_proxyans1->Method == 2)
# V( |* w+ U3 }4 F% C6 b{
/ r  X; m/ Q6 k& F! {int nUserLen = strlen(g_ProxyInfo.m_strProxyUser);
int nPassLen = strlen(g_ProxyInfo.m_strProxyPass);
# ~- ~" \+ K- W" V% a* N2 b- v. K# Gstruct authreq *m_authreq;
m_authreq = (struct authreq *)buff;
) M) O0 F. y, H+ Qm_authreq->Ver = 1;
0 D3 v5 m8 c. @, x$ U% t9 sm_authreq->Ulen = nUserLen;
strcpy(m_authreq->Name,g_ProxyInfo.m_strProxyUser);
m_authreq-&gtLen = nPassLen;
6 I8 V% m; X4 Y  L$ O% o9 qstrcpy(m_authreq-&gtass,g_ProxyInfo.m_strProxyPass);
" r$ ]* H+ ]0 PClientSock.Send(buff,513);
struct authans *m_authans;
m_authans = (struct authans *)buff;
. C# G7 u4 s7 I8 ]! |- E, ymemset(buff,0,600);
, ^' q) y' G9 {& E+ y' j2 B) {ClientSock.Receive(buff,600);
6 r. F1 V9 A  v+ s) N* H. \9 S$ hif(m_authans->Ver != 1 || m_authans->Status != 0)
* q- D& e  t& O  u% O6 {{
m_sError = _T("代理服务器用户验证不成功!");
2 e; |7 e* |  g# F5 }. bClientSock.Close();
& C! F: `* c  V* ^' Lreturn FALSE;
/ t0 j* l7 z2 ?* Y  K; W}
}
' A+ b1 a& `; @$ f* N+ ~& k* {struct sock5req2 *m_proxyreq2;
- G3 ~5 \, i( f; Mm_proxyreq2 = (struct sock5req2 *)buff;
: w" Q; V& [1 c  i/ C6 Y& H3 Qm_proxyreq2->Ver = 5;
m_proxyreq2->Cmd = 1;
m_proxyreq2->Rsv = 0;
6 c4 \" Z- W. w* _7 Nm_proxyreq2->Atyp = 1;
9 N9 X- S% a; W3 Iunsigned long tmpLong = inet_addr(GetServerHostName());
7 ^5 \/ i( _4 E, W1 |unsigned short port = ntohs(GetPort());
memcpy(m_proxyreq2->other,&tmpLong,4);
5 ?7 u, L5 ]% k/ C' u- ~2 ]4 Mmemcpy(m_proxyreq2->other+4,&port,2);
$ F% M& l7 R6 y- @' z: {( s  i& AClientSock.Send(buff,sizeof(struct sock5req2)+5);
struct sock5ans2 *m_proxyans2;
2 R5 E1 j. G5 ~4 g0 ^# qmemset(buff,0,600);
3 d4 `( n, i4 u' s0 I# Dm_proxyans2 = (struct sock5ans2 *)buff;
+ k7 P- ^) X/ `3 ]3 R; sClientSock.Receive(buff,600);
; c! b! M8 i- _& h0 U8 \, nif(m_proxyans2->Ver != 5 || m_proxyans2->Rep != 0)
+ r+ X& x, s4 w* a' c{
) V8 ?3 Z( Y1 E6 E" x1 Z8 Am_sError = _T("通过代理连接主站不成功!");
ClientSock.Close();
+ y) E4 s3 o$ C. o8 k* @# U+ Zreturn FALSE;
}
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: n/ D% q& r6 ^9 K5 \
& J: Z# Q+ _; i//通过HTTP方式代理
3 r1 ~" _- o, v, k, r, Y' q, kif( !ClientSock.Connect( g_ProxyInfo.m_strProxyIP,g_ProxyInfo.m_nProxyPort) )
{
m_sError = _T("不能连接到代理服务器!");
! P- J1 w& F0 c, n# A) p" xClientSock.Close();
# b* v1 H! d+ ^" Sreturn FALSE;
}
char buff[600];
9 y2 ~( L4 W6 V( x7 {% I" j( ~. g5 ~sprintf( buff, "%s%s:%d%s","CONNECT ",GetServerHostName(),GetPort()," HTTP/1.1\r\nUser-Agent: MyApp/0.1\r\n\r\n");
& ~. d6 q& u# F$ }ClientSock.Send(buff,strlen(buff)); //发送请求
memset(buff,0,600);
8 o6 F( g, e' J* d$ w8 Q( V( eClientSock.Receive(buff,600);
if(strstr(buff, "HTTP/1.0 200 Connection established") == NULL) //连接不成功
0 {- b6 f, C" z# y# W5 [{
m_sError = _T("通过代理连接主站不成功!");
ClientSock.Close();
, S3 c5 }6 y) I: C6 o* Q, L/ ^return FALSE;
}
我们一般先与代理服务器连通，然后向代理服务器发送代理验证的用户名和密码(如果需要,如Socks5代理)，验证成功后，再向代理服务器发送需要连接的目的地址和端口。以上代码仅用于TCP连接，如果在内部网侦听或通过UDP协议发送信息，可查阅RFC1829等文档资料。