开通博客赚积分
发布资源赚积分
分类

源码开发语言/平台
当前位置：首页 > 源码/资料 > Internet/网络编程 > TCP/IP协议栈 > 查看源码
Packet.cpp
资源名称：PPP0208.rar　[点击查看]
上传用户：karykuang
上传日期：2010-02-26
资源大小：103k
文件大小：21k
源码类别：

TCP/IP协议栈

开发平台：

Visual C++

Packet.cpp：源码内容
  1. // Packet.cpp: implementation of the CPacket class.
  2. //
  3. //////////////////////////////////////////////////////////////////////
  5. #include "stdafx.h"
  6. #include "demo.h"
  7. #include "Packet.h"
  10. #ifdef _DEBUG
  11. #undef THIS_FILE
  12. static char THIS_FILE[]=__FILE__;
  13. #define new DEBUG_NEW
  14. #endif
  16. //////////////////////////////////////////////////////////////////////
  17. // Construction/Destruction
  18. //////////////////////////////////////////////////////////////////////
  20. CPacket::CPacket()
  21. {
  23. TxLen=0;
  24. reject=FALSE;
  25. map=FALSE;
  26. recPacketS=0;
  27. IPCP_s=0;
  28. bID=1;
  29. bState=INITIAL;
  30. compress=0;
  31. PF_compress=0;
  32. for(int i=0;i<8;i++)
  33. {
  34. option[i].reject=TRUE;
  35. memset(option[i].bData,0x0,64);
  36. }
  37. memset(bPacketTx,0x0,256);
  38. memset(bIpaddress,0x00,4);
  39. iHeadcheckpos=0;
  41. iLenpos=0;
  42. }
  46. CPacket::~CPacket()
  47. {
  49. }
  52. bool CPacket::checkpacket(BYTE* pPacketstr)
  53. {
  54. BYTE bCode;
  55. CCRC m_crc;
  56. memset(bPacketTx,0x00,256);
  57. memset(bPacketTx1,0x00,256);
  58. TxLen=0;
  60. if ( (pPacketstr[3-compress]&1) && (pPacketstr[3-compress]!=0xff) )
  61. {
  62. wType=pPacketstr[3-compress];
  64. }
  65. else wType=pPacketstr[3-compress]*256+pPacketstr[4-compress];
  67. switch(wType){
  68. case LCP:
  69. {
  70. bCode=pPacketstr[5-compress];
  71. bID=pPacketstr[6-compress];
  72. switch(bCode){
  73. case REQ:
  74. /*if (bState==LCPOPEN) 
  75. {
  76. bState=INITIAL;
  77. reject=FALSE;
  78. testoption(wType,bCode,pPacketstr);
  79. makepacket(wType,bCode,pPacketstr);
  80. }
  81. else
  82. */
  83. {
  84. testoption(wType,bCode,pPacketstr);
  85. makepacket(wType,bCode,pPacketstr);
  86. }
  87. break;//end REQ
  88. case ACK:
  89. //if (pPacketstr[6]!=bID) break;
  91. testoption(wType,bCode,pPacketstr);
  92. memset(bPacketTx,0x00,256);
  93. bState=PAPOPEN;
  94. makepacket(PAP,REQ,bPacketTx);
  95. break;//end ACK
  96. case NAK:
  98. break;//end NAK
  99. case REJ:
  101. break;//end REJ
  102. case ECHO_REQ:
  103. testoption(wType,bCode,pPacketstr);
  104. memset(bPacketTx,0x00,256);
  105. makepacket(wType,bCode,bPacketTx);
  108. break;//end TERM
  109. default:
  110. break;
  111. }//end code
  113. break;
  114. }//end LCP
  115. case PAP:
  116. bCode=pPacketstr[5-compress];
  117. bID=pPacketstr[6-compress];
  118. switch(bCode){
  119. case REQ:
  120. break;
  121. case ACK:
  123. bState=PAPPASS;
  124. memset(bPacketTx,0x00,256);
  125. makepacket(IPCP,REQ,bPacketTx);
  126. break;
  127. case NAK:
  128. break;
  129. default:
  130. break;
  131. }//end switch
  132. break;//end PAP
  133. case IPCP:
  134. bCode=pPacketstr[5-compress];
  135. bID=pPacketstr[6-compress];
  136. switch(bCode){
  137. case REQ:
  138. testoption(wType,bCode,pPacketstr);
  139. if (bState<IPCPOPEN && reject==false) bState=IPCPOPEN;
  140. if (bState==IPCPOK)
  141. {
  142. IPCP_s=IPCPREOPEN;
  143. //makepacket(wType,NAK,pPacketstr);
  144. }
  145. //else 
  146. makepacket(wType,ACK,pPacketstr);
  147. break;
  148. case ACK:
  149. if (bState<IPCPOK) bState=IPCPOK;
  150. break;
  151. case NAK:
  152. testoption(wType,bCode,pPacketstr);
  153. if (bState<IPCPNAK && reject==false) bState=IPCPNAK;
  154. makepacket(wType,REQ,pPacketstr);
  155. break;
  156. default:
  157. break;
  158. }//end switch
  159. break;//end IPCP
  160. case IP:
  161. IP_header.protocol=pPacketstr[14-compress-PF_compress];
  162. int k;
  163. k=16-compress-PF_compress+1;
  164. IP_header.SrcIP[0]=pPacketstr[k++];
  165. IP_header.SrcIP[1]=pPacketstr[k++];
  166. IP_header.SrcIP[2]=pPacketstr[k++];
  167. IP_header.SrcIP[3]=pPacketstr[k++];
  168. IP_header.DesIP[0]=pPacketstr[k++];
  169. IP_header.DesIP[1]=pPacketstr[k++];
  170. IP_header.DesIP[2]=pPacketstr[k++];
  171. IP_header.DesIP[3]=pPacketstr[k++];
  173. switch(IP_header.protocol)
  174. {
  175. case IP_ICMP:
  176. ICMP_header.type=pPacketstr[25-compress-PF_compress];
  177. switch (ICMP_header.type)
  178. {
  179. case ICMP_PING:
  180. makeIPpacket(IP_ICMP,ICMP_PINGREPLY,pPacketstr-compress-PF_compress+5);
  181. break;
  182. case ICMP_PINGREPLY:
  183. recPacketS=1;
  184. break;
  185. default:
  186. break;
  187. }
  188. //bCode=PING;
  189. //testoption(wType,bCode,pPacketstr);
  190. //makepacket(wType,bCode,pPacketstr);
  191. break;//end IP
  192. case IP_UDP:
  193. //format of temp for udp:
  194. //destination address
  195. //source port
  196. //destination port
  197. //udp data length
  198. //udp check sum 2bytes msb +lsb
  199. //udp data
  201. //m_packet.makeIPpacket(IP_UDP,NULL,temp);
  203. break;
  204. default:
  205. break;
  206. }
  207. break;
  208. case CCP:
  209. break;//end CCP
  210. default:
  211. break;
  212. }//end case
  213. return true;
  214. }
  216. void CPacket::testoption(WORD wType,BYTE bCode,BYTE* pOptionstr)
  217. {
  218. WORD wSize,wStart;
  219. int i=0,j=0,k;
  220. DWORD dwMagic;
  222. reject=FALSE;
  223. srand((unsigned)time(NULL));
  224. dwMagic=rand();
  225. wStart=9-compress;
  226. wSize=pOptionstr[7-compress]*256+pOptionstr[8-compress]+8-compress;//length+framebegin(3)+protocol(2)+checksum(2)+frameend(1)
  227. if (wSize>MAXRX-8) wSize=MAXRX-8-compress; //truncate packet if larger than buffer
  229. for(k=0;k<8;k++)
  230. {
  231. option[k].reject=TRUE;
  232. memset(option[k].bData,0x0,64);
  233. }
  235. while(wStart<wSize-3)
  236. {
  237. option[j].bType=pOptionstr[wStart++];
  238. option[j].bLength=pOptionstr[wStart++];
  239. for (i=0;i<option[j].bLength-2;i++)
  240. {
  241. option[j].bData[i]=pOptionstr[i+wStart];
  242. }//end for
  243. option[j].bData[i]='';
  244. wStart=i+wStart;
  245. j++;
  246. }//end while
  247. iOptionnum=j;
  249. switch(wType)
  250. {
  251. case LCP:
  252. {
  253. for(i=0;i<j;i++)
  254. {
  255. if (option[i].bType>0 && option[i].bType<=29)
  256. {
  257. switch(option[i].bType)
  258. {
  259. case 1: //Maximum Receive Unit
  260. option[i].reject=FALSE;
  261. //option[i].bData[0]=0x00;
  262. //option[i].bData[1]=0xff;
  263. //option[i].bLength=0x04;
  264. break;
  266. case 2: //Async-Control-Character-Map
  267. option[i].reject=FALSE;
  268. map=TRUE;
  269. break;
  271. case 3: //Authentication-protocol
  272. option[i].reject=TRUE;
  273. reject=TRUE;
  274. break;
  276. case 5: //Magic-number
  277. option[i].reject=TRUE;
  278. reject=TRUE;
  279. //option[i].reject=FALSE;
  280. //option[i].bData[3]=dwMagic & 0x00ff;
  281. //option[i].bData[2]=(dwMagic>>8) & 0x00ff;
  282. //option[i].bData[1]=(dwMagic>>16) & 0x00ff;
  283. //option[i].bData[0]=(dwMagic>>24) & 0x00ff;;
  284. //option[i].bLength=0x06;
  285. break;
  287. case 7: //Protocol-Field-Compression
  288. option[i].reject=FALSE;
  289. PF_compress=1;
  290. break;
  292. case 8: //Address-and-Control-Field-Compression
  293. option[i].reject=FALSE;
  294. if(bCode==ACK)
  295. compress=2;
  296. break;
  297. /*
  298. case 0x11: //Numbered-Mode
  299. option[i].reject=FALSE;
  300. break;
  302. case 0x13: //Callback
  303. option[i].reject=FALSE;
  304. break;
  305. */
  307. default://reject the rest
  308. option[i].reject=TRUE;
  309. reject=TRUE;
  310. break;
  311. }//end switch
  312. }else
  313. {
  314. //wrong options
  315. }//end if ...option type
  317. }//end for
  318. break;
  319. }//end case LCP
  321. case IPCP:
  322. for(i=0;i<j;i++)
  323. {
  324. if ((option[i].bType>0 && option[i].bType<5)||(option[i].bType>=129 && option[i].bType<=132) )
  325. {
  326. switch(option[i].bType)
  327. {
  328. case 1: //ip addresses
  329. option[i].reject=TRUE;
  330. reject=TRUE;
  331. break;
  332. case 2: //ip compression protocol
  333. option[i].reject=TRUE;
  334. reject=TRUE;
  335. // option[i].reject=FALSE;
  336. break;
  337. case 3: //ip address
  338. option[i].reject=FALSE;
  339.      //if (bCode==ACK)
  340. if (bCode==NAK)
  341. {
  342. for (k=0;k<option[i].bLength-2;k++)
  343. {
  344. bIpaddress[k]=option[i].bData[k];
  345. }//end for
  346. }//end if
  347. break;
  348. default://reject the rest
  349. option[i].reject=TRUE;
  350. reject=TRUE;
  351. break;
  352. }//end switch
  353. }//end if 
  354. }//end for
  355. break;
  356. }
  357. }
  359. void CPacket::makepacket(WORD wType,BYTE bCode,BYTE* pPacketRx)
  360. {
  362. int i,j,k;
  363. WORD wLen,whigh=0,wlow=0;//header checksum;
  364. int iHeadpos;
  365. WORD wChecksum;
  368. memset(bPacketTx,0x00,256);
  369. memset(bPacketTx1,0x00,256);
  371. i=0;
  372. bPacketTx[i++]=0x7e;//frame header
  373. switch(wType)
  374. {
  375. case LCP:
  376. switch(bCode)
  377. {
  378. case REQ:
  379. for(i=1;i<5;i++)
  380. {
  381. bPacketTx[i]=pPacketRx[i];//frame head and protocol
  383. }
  384. if(reject)
  385. {
  386. bCode=REJ;
  387. }
  388. else//ack
  389. {
  390. bCode=ACK;
  391. }//end if(reject)
  393. bPacketTx[i++]=bCode;//code
  394. bPacketTx[i++]=bID;//id
  395. iLenpos=i;//get the length postion
  396. i+=2;
  398. for(k=0;k<iOptionnum;k++)
  399. {
  400. if(bCode==REJ && option[k].reject)
  401. {
  402. bPacketTx[i++]=option[k].bType;
  403. bPacketTx[i++]=option[k].bLength;
  404. for(j=0;j<option[k].bLength-2;j++)
  405. bPacketTx[i++]=option[k].bData[j];
  406. }//end if(option[i].reject&& szCode==REJ)
  407. if(bCode==ACK && !option[k].reject)
  408. {
  410. bState=LCPOPEN;//ZJ 0619
  411. bPacketTx[i++]=option[k].bType;
  412. bPacketTx[i++]=option[k].bLength;
  413. for(j=0;j<option[k].bLength-2;j++)
  414. bPacketTx[i++]=option[k].bData[j];
  415. }//end if(!option[i].reject&& szCode==ACK)
  416. }//end for
  418. break;//REQ
  419. case ACK:
  420. for(i=1;i<5;i++)
  421. {
  422. bPacketTx[i]=pPacketRx[i];//frame head and protocol
  423. }
  424. bPacketTx[i++]=REQ;//code
  425. bPacketTx[i++]=bID;//id
  426. iLenpos=i;//get the length postion
  427. i+=2;
  428. while(pPacketRx[i]!=0x7e)
  429. {
  430. bPacketTx[i]=pPacketRx[i];
  431. i++;
  432. }
  433. i-=2;
  434. bPacketTx[i]='';
  435. bPacketTx[i+1]='';
  436. break;//end ACK
  437. case ECHO_REQ:
  438. for(i=1;i<5;i++)
  439. {
  440. bPacketTx[i]=pPacketRx[i];//frame head and protocol
  441. }
  442. bPacketTx[i++]=ECHO_REP;//code
  443. bPacketTx[i++]=bID;//id
  444. iLenpos=i;//get the length postion
  445. i+=2;
  446. while(pPacketRx[i]!=0x7e)
  447. {
  448. bPacketTx[i]=pPacketRx[i];
  449. i++;
  450. }
  451. i-=2;
  452. bPacketTx[i]='';
  453. bPacketTx[i+1]='';
  454. break;//ECHO_REQ
  456. }//end switch code
  457. break;//end LCP
  458. case PAP:
  459. bPacketTx[i++]=0xff;
  460. bPacketTx[i++]=0x03;
  461. bPacketTx[i++]=0xc0;
  462. bPacketTx[i++]=0x23;
  463. bPacketTx[i++]=bCode;
  464. bPacketTx[i++]=bID;
  465. iLenpos=i;
  466. i+=2;
  467. bPacketTx[i++]=0x06;
  468. bPacketTx[i++]='1';
  469. bPacketTx[i++]='6';
  470. bPacketTx[i++]='3';
  471. bPacketTx[i++]=0x08;
  472. bPacketTx[i++]='1';
  473. bPacketTx[i++]='6';
  474. bPacketTx[i++]='3';
  475. break;//end PAP
  476. case IPCP:
  477. for(i=1;i<5-compress;i++)
  478. {
  479. bPacketTx[i]=pPacketRx[i];//frame head and protocol
  480. }
  481. if(reject) bCode=REJ;
  482. /*
  483. else
  484. {
  485. if( bState < IPCPOPEN ) //WCY
  486. bCode=REQ;
  487. else
  488. bCode=ACK;
  489. }
  490. */
  492. //end if(reject)
  493. bPacketTx[i++]=bCode;//code
  494. bPacketTx[i++]=bID;//id
  495. iLenpos=i;//get the length postion
  496. i+=2;
  498. for(k=0;k<iOptionnum;k++)
  499. {
  500. if(bCode==REJ && option[k].reject)
  501. {
  502. bPacketTx[i++]=option[k].bType;
  503. bPacketTx[i++]=option[k].bLength;
  504. for(j=0;j<option[k].bLength-2;j++)
  505. bPacketTx[i++]=option[k].bData[j];
  506. }//end if(option[i].reject&& bCode==REJ)
  507. else if((bCode==REQ) || (bCode==ACK) || (bCode==NAK) && (!option[k].reject))
  508. {
  509. //switch(bCode){
  510. //case REQ:
  511. // bState=IPCPOPEN;
  512. // break;
  513. //case ACK:
  514. // bState=IPCPACK;
  515. // break;
  516. //}
  517. if (bCode==REQ  && bState==IPCPOPEN) 
  518. {
  519. bPacketTx[i++]=3;
  520. bPacketTx[i++]=6;
  521. for(j=0;j<option[k].bLength-2;j++)
  522. bPacketTx[i++]=0;
  523. }else if (bCode==NAK)
  524. {
  525. bPacketTx[i++]=3;
  526. bPacketTx[i++]=6;
  527. for(j=0;j<option[k].bLength-2;j++)
  528. bPacketTx[i++]=bIpaddress[j];
  529. }
  530. else 
  531. {
  532. bPacketTx[i++]=option[k].bType;
  533. bPacketTx[i++]=option[k].bLength;
  534. for(j=0;j<option[k].bLength-2;j++)
  535. bPacketTx[i++]=option[k].bData[j];
  536. }
  537. }//end if(!option[i].reject&& bCode==ACK || bCode==REQ))
  538. }//end for
  539. break;//end IPCP
  540. /*
  541. case IP:
  542. if(compress==0)
  543. {
  544. bPacketTx[i++]=0xff;
  545. bPacketTx[i++]=0x03;
  546. }
  547. if (PF_compress!=1)
  548. bPacketTx[i++]=0x00;
  549. bPacketTx[i++]=0x21;
  550. switch(bCode)
  551. {
  552. case PING:
  553. iHeadpos=i;
  554. i=ipheader(i);
  555. for(j=0;j<4;j++)
  556. {
  557. bPacketTx[i++]=bIpaddress[j];//source ip address
  558. }
  559. for(j=0;j<4;j++)
  560. {
  561. bPacketTx[i++]=pPacketRx[j];//destination ip address
  562. }
  563. bPacketTx[i++]=0x08;//ICMP type 请求回显
  564. bPacketTx[i++]=bCode;//ICMP code
  565. iIcmpcheckpos=i;
  566. bPacketTx[i++]=0x00;//icmp checksum set 0
  567. bPacketTx[i++]=0x00;//icmp checksum set 0
  568. bPacketTx[i++]=0x00;
  569. bPacketTx[i++]=0x01;
  570. bPacketTx[i++]=0x00;
  571. bPacketTx[i++]=bID;
  572. wlow=0;
  573. whigh=0;
  574. for(j=iIcmpcheckpos-2;j<i;j+=2)
  575. {
  576. whigh+=bPacketTx[j];
  577. }
  578. for(j=iIcmpcheckpos-1;j<i;j+=2)
  579. {
  580. wlow+=bPacketTx[j];
  581. }
  582. wlow+=whigh/256;
  583. whigh=(whigh & 255)+wlow/256;
  584. wlow=(wlow & 255)+whigh/256;
  585. whigh=~whigh;
  586. wlow=~wlow;
  587. bPacketTx[iIcmpcheckpos++]=(whigh & 0x00ff);
  588. bPacketTx[iIcmpcheckpos]=(wlow & 0x00ff);
  589. break;//end case ping
  590. default:
  591. memset(bPacketTx,0x00,256);
  592. break;
  593. }
  594. break;//end IP
  595. */
  596. case CCP:
  597. break;//end CCP
  598. default:
  599. break;
  600. }//end switch type
  601. if (wType==IP)
  602. {
  603. wLen=i-5+compress+PF_compress;
  604. bPacketTx[iLenpos++]=wLen/256;
  605. bPacketTx[iLenpos]=wLen%256;
  606. wlow=0;
  607. whigh=0;
  608. for(j=iHeadpos;j<20+iHeadpos;j+=2)
  609. {
  610. whigh+=bPacketTx[j];
  611. }
  612. for(j=iHeadpos+1;j<=20+iHeadpos;j+=2)
  613. {
  614. wlow+=bPacketTx[j];
  615. }
  616. wlow+=whigh/256;
  617. whigh=(whigh & 255)+wlow/256;
  618. wlow=(wlow & 255)+whigh/256;
  619. whigh=~whigh;
  620. wlow=~wlow;
  621. bPacketTx[iHeadcheckpos++]=(whigh & 0x00ff);
  622. bPacketTx[iHeadcheckpos]=(wlow & 0x00ff);
  623. }
  624. else 
  625. {
  626. wLen=i-5+compress;
  627. bPacketTx[iLenpos++]=wLen/256;
  628. bPacketTx[iLenpos]=wLen%256;
  630. }
  631. wChecksum=m_crc.CountCRC(bPacketTx+1,i-1);//get checksum and copy to szPacketTx[crcpos]
  632. wChecksum=~wChecksum;
  633. bPacketTx[i++]=(wChecksum & 0x00ff);
  634. bPacketTx[i++]=((wChecksum>>8) & 0x00ff);
  638. int ii;
  639. for (ii=0; ii<i; ii++)
  640. bPacketTx1[ii]=bPacketTx[ii];
  642. for (ii=i; ii<256; ii++) bPacketTx1[ii]=0xcc;
  643. bPacketTx1[i]=0x7e;
  645. i=charactermap(i);
  646. bPacketTx[i]=0x7e;//and framing end 0x7e
  647. TxLen=i+1;
  648. bID++;
  649. reject=FALSE;
  650. }
  652. int CPacket::charactermap(int iLen)
  653. {
  654. BYTE temp,endtemp;
  655. int i,j;
  657. for(i=1;i<iLen;i++)
  658. {
  659. if(bPacketTx[i]>=0x00 && bPacketTx[i]<0x20)
  660. {
  661. endtemp=bPacketTx[iLen++];
  662. for(j=iLen-1;j>i;j--)
  663. {
  664. temp=bPacketTx[j];
  665. bPacketTx[j+1]=temp;
  666. }
  667. temp=bPacketTx[i]+0x20;
  668. bPacketTx[i++]=0x7d;
  669. bPacketTx[i]=temp;
  670. bPacketTx[iLen]=endtemp;
  671. }//end if 0x00-0x20
  672. else if(bPacketTx[i]==0x7d)
  673. {
  674. endtemp=bPacketTx[iLen++];
  675. for(j=iLen-1;j>i;j--)
  676. {
  677. temp=bPacketTx[j];
  678. bPacketTx[j+1]=temp;
  679. }
  680. temp=0x5d;
  681. bPacketTx[i++]=0x7d;
  682. bPacketTx[i]=temp;
  683. bPacketTx[iLen]=endtemp;
  684. }//end if 0x7d
  685. else if(bPacketTx[i]==0x7e)
  686. {
  687. endtemp=bPacketTx[iLen++];
  688. for(j=iLen-1;j>i;j--)
  689. {
  690. temp=bPacketTx[j];
  691. bPacketTx[j+1]=temp;
  692. }
  693. temp=0x5e;
  694. bPacketTx[i++]=0x7d;
  695. bPacketTx[i]=temp;
  696. bPacketTx[iLen]=endtemp;
  697. }//end if 0x7e
  698. }//end main for
  699. return(iLen);
  700. }
  701. int CPacket::ipheader(int i)
  702. {
  703. bPacketTx[i++]=0x45;//version and header length
  704. bPacketTx[i++]=0x00;//service
  705. iLenpos=i; //total length position
  706. i+=2;
  707. bPacketTx[i++]=0x88;//identification-MSB
  708. bPacketTx[i++]=0x10;//identification-LSB
  709. bPacketTx[i++]=0x40;//flags
  710. bPacketTx[i++]=0x00;//fragment offset
  711. bPacketTx[i++]=0x7f;//TTL
  712. bPacketTx[i++]=0x01;//protocol
  713. iHeadcheckpos=i;
  714. bPacketTx[i++]=0x00;//header checksum
  715. bPacketTx[i++]=0x00;//header checksum
  716. return i;
  717. }
  719. void CPacket::InitPacket()
  720. {
  723. TxLen=0;
  724. reject=FALSE;
  725. map=FALSE;
  726. recPacketS=0;
  727. IPCP_s=0;
  728. bID=1;
  729. bState=INITIAL;
  730. compress=0;
  731. PF_compress=0;
  732. for(int i=0;i<8;i++)
  733. {
  734. option[i].reject=TRUE;
  735. memset(option[i].bData,0x0,64);
  736. }
  737. memset(bPacketTx,0x0,256);
  738. memset(bIpaddress,0x00,4);
  739. iHeadcheckpos=0;
  741. iLenpos=0;
  742. }
  744. void CPacket::makeIPpacket(BYTE protocal, BYTE type, BYTE *temp)
  745. {
  746. // this function need optimization of the process when not support for protcal or type
  748. int i,j,k;
  749. WORD wLen,whigh=0,wlow=0;//header checksum;
  750. int iHeadpos,TTLpos;
  751. WORD wChecksum;
  753. memset(bPacketTx,0x00,256);
  754. memset(bPacketTx1,0x00,256);
  756. i=0;
  757. bPacketTx[i++]=0x7e;//frame header
  759. if(compress==0)
  760. {
  761. bPacketTx[i++]=0xff;
  762. bPacketTx[i++]=0x03;
  763. }
  764. if (PF_compress!=1)
  765. bPacketTx[i++]=0x00;
  766. bPacketTx[i++]=0x21;
  767. iHeadpos=i;
  769. bPacketTx[i++]=0x45;//version and header length
  770. bPacketTx[i++]=0x00;//service
  771. iLenpos=i; //total length position
  772. i+=2;
  773. bPacketTx[i++]=IP_headerTx.Identification >> 8; //identification-MSB
  774. bPacketTx[i++]=IP_headerTx.Identification & 0xff; //identification-LSB
  775. IP_headerTx.Identification++;
  776. bPacketTx[i++]=0x00;//0x40;//flags
  777. bPacketTx[i++]=0x00;//fragment offset
  778. TTLpos=i;
  779. bPacketTx[i++]=0x7f;//TTL
  780. bPacketTx[i++]=protocal;//protocol
  781. iHeadcheckpos=i;
  782. bPacketTx[i++]=0x00;//header checksum
  783. bPacketTx[i++]=0x00;//header checksum
  784. for(j=0;j<4;j++)
  785. {
  786. bPacketTx[i++]=bIpaddress[j];//source ip address
  787. }
  789. switch(protocal)
  790. {
  791. case IP_ICMP:
  792. switch(type)
  793. {
  794. case ICMP_PING:
  795. //format of temp for ping
  796. //destination address 4bytes
  797. //ping data length 2bytes, msb lsb
  798. //ping data 
  800. for(j=0;j<4;j++)
  801. {
  802. bPacketTx[i++]=temp[j];//destination ip address
  803. }
  804. bPacketTx[i++]=type;//ICMP type 请求回显
  805. bPacketTx[i++]=00;//ICMP code
  806. iIcmpcheckpos=i;
  807. bPacketTx[i++]=0x00;//icmp checksum set 0
  808. bPacketTx[i++]=0x00;//icmp checksum set 0
  809. bPacketTx[i++]=0x00;
  810. bPacketTx[i++]=0x01;
  811. bPacketTx[i++]=ICMP_header.sequence & 0x00ff; //sequence number lsb
  812. bPacketTx[i++]=ICMP_header.sequence >> 8; //sequence number msb
  813. ICMP_header.sequence++;
  814. k=temp[4]*256+temp[5];
  816. for (j=0;j<k;j++)
  817. {
  818. bPacketTx[i++]=temp[6+j];
  819. }
  821. break;
  822. case ICMP_PINGREPLY:
  823. //format of temp for ping
  824. //recieved data start at the data 0x45....
  825. bPacketTx[TTLpos]=temp[8]-1;
  826. for(j=0;j<4;j++)
  827. {
  828. bPacketTx[i++]=temp[j+12];//destination ip address
  829. }
  830. bPacketTx[i++]=type; //ICMP type 回显应答
  831. bPacketTx[i++]=00; //ICMP code
  832. iIcmpcheckpos=i;
  833. bPacketTx[i++]=0x00; //icmp checksum set 0
  834. bPacketTx[i++]=0x00; //icmp checksum set 0
  835. bPacketTx[i++]=temp[24];
  836. bPacketTx[i++]=temp[25];
  837. bPacketTx[i++]=temp[26]; //reply the same sequence number
  838. bPacketTx[i++]=temp[27]; //reply the same sequence number
  840. int jj,kk;
  841. kk=0;
  842. kk+=temp[2]*256+temp[3];
  843. jj=28;
  844. for (;jj<kk;) 
  845. bPacketTx[i++]=temp[jj++]; //copy the last data
  846. break;
  847. default:
  848. break;
  849. }
  850. //count the icmp checksum
  851. wlow=0;
  852. whigh=0;
  853. for(j=iIcmpcheckpos-2;j<i;j+=2)
  854. {
  855. whigh+=bPacketTx[j];
  856. }
  857. for(j=iIcmpcheckpos-1;j<i;j+=2)
  858. {
  859. wlow+=bPacketTx[j];
  860. }
  862. //write the sub header checksum
  863. wlow+=whigh/256;
  864. whigh=(whigh & 255)+wlow/256;
  865. wlow=(wlow & 255)+whigh/256;
  866. whigh=~whigh;
  867. wlow=~wlow;
  868. bPacketTx[iIcmpcheckpos++]=(whigh & 0x00ff);
  869. bPacketTx[iIcmpcheckpos]=(wlow & 0x00ff);
  871. break;
  872. case IP_UDP:
  873. //format of temp for udp:
  874. //destination address 4bytes
  876. //source port 2bytes msb+lsb
  877. //destination port  2bytes msb+lsb
  878. //udp data length 2bytes msb +lsb temp[8]:temp[9]
  879. //udp check sum 2bytes msb +lsb (from source port to the end of the udp_data)
  880. //udp data temp[12]
  881. for(j=0;j<10;j++)
  882. {
  883. bPacketTx[i++]=temp[j];//destination ip address
  884. }
  885. iIcmpcheckpos=i;
  886. bPacketTx[i++]=0;
  887. bPacketTx[i++]=0;
  889. k=temp[8]*256+temp[9]+4;
  890. for(j=12;j<k;j++)
  891. {
  892. bPacketTx[i++]=temp[j];//destination ip address
  893. }
  895. //attention
  896. //the check sum of udp is include:
  897. //pseudo header,UDP header,UDP data
  898. //pseudo header include :12bytes
  899. //source ip address(4b)
  900. //destination ip address(4b)
  901. //0(1b), ip protocol(1b), and udp length(2b)
  903. wlow=0;
  904. whigh=0;
  905. for(j=iIcmpcheckpos-14;j<i;j+=2)
  906. {
  907. whigh+=bPacketTx[j];
  908. }
  909. for(j=iIcmpcheckpos-13;j<i;j+=2)
  910. {
  911. wlow+=bPacketTx[j];
  912. }
  913. whigh+=temp[8];
  914. wlow+=protocal;
  915. wlow+=temp[9];
  918. //write the sub header checksum
  919. wlow+=whigh/256;
  920. whigh=(whigh & 255)+wlow/256;
  921. wlow=(wlow & 255)+whigh/256;
  922. whigh=~whigh;
  923. wlow=~wlow;
  924. bPacketTx[iIcmpcheckpos++]=(whigh & 0x00ff);
  925. bPacketTx[iIcmpcheckpos]=(wlow & 0x00ff);
  928. default:
  929. break;
  930. }
  932. k=16-compress-PF_compress+1;
  933. IP_header.SrcIP[0]=bPacketTx[k++];
  934. IP_header.SrcIP[1]=bPacketTx[k++];
  935. IP_header.SrcIP[2]=bPacketTx[k++];
  936. IP_header.SrcIP[3]=bPacketTx[k++];
  937. IP_header.DesIP[0]=bPacketTx[k++];
  938. IP_header.DesIP[1]=bPacketTx[k++];
  939. IP_header.DesIP[2]=bPacketTx[k++];
  940. IP_header.DesIP[3]=bPacketTx[k++];
  942. wLen=i-5+compress+PF_compress;
  943. bPacketTx[iLenpos++]=wLen/256;
  944. bPacketTx[iLenpos]=wLen%256;
  947. //count the ip header's checksum
  948. wlow=0;
  949. whigh=0;
  950. for(j=iHeadpos;j<20+iHeadpos;j+=2)
  951. {
  952. whigh+=bPacketTx[j];
  953. }
  954. for(j=iHeadpos+1;j<=20+iHeadpos;j+=2)
  955. {
  956. wlow+=bPacketTx[j];
  957. }
  958. wlow+=whigh/256;
  959. whigh=(whigh & 255)+wlow/256;
  960. wlow=(wlow & 255)+whigh/256;
  961. whigh=~whigh;
  962. wlow=~wlow;
  963. bPacketTx[iHeadcheckpos++]=(whigh & 0x00ff);
  964. bPacketTx[iHeadcheckpos]=(wlow & 0x00ff);
  966. wChecksum=m_crc.CountCRC(bPacketTx+1,i-1);//get checksum and copy to szPacketTx[crcpos]
  967. wChecksum=~wChecksum;
  968. bPacketTx[i++]=(wChecksum & 0x00ff);
  969. bPacketTx[i++]=((wChecksum>>8) & 0x00ff);
  973. int ii;
  974. for (ii=0; ii<i; ii++)
  975. bPacketTx1[ii]=bPacketTx[ii];
  977. for (ii=i; ii<256; ii++) bPacketTx1[ii]=0xcc;
  978. bPacketTx1[i]=0x7e;
  980. i=charactermap(i);
  981. bPacketTx[i]=0x7e;//and framing end 0x7e
  982. TxLen=i+1;
  983. bID++;
  984. reject=FALSE;
  986. }