迎接ChinaUnix九周年庆技术实践之二----C/C++编程大赛！-结果公布！

pincs

我也占个位先

surpass_li

回复  surpass_li


    第一贴上面有阿，发邮件！！
rubylc_unix 发表于 2010-12-01 12:38

    代码已经发给您了

renxiao2003

第一题难度也不高。已基本完成。晚上提交。

renxiao2003

提交了第一题答案，在cygwin环境下通过。
不知道在其他环境下会不会有问题啊。

renxiao2003

二四题的难度太高了。都没找到参考资料。难哦。

jhui66

可惜不太懂PHP

surpass_li

努力查找资料 域名取IP 做出来了，晚上提交代码：）

renxiao2003

回复 77# surpass_li


    厉害。哥昨天就提交代码了。你比我慢一步。

xiaocong004

看起来不难，做起来，想做好还需要费一番脑子。

heut2009

第二题
写出个有bug的半成品，望各位给指点指点，给点意见，我好想拿个奖啊。

1. 
   
2. 
   
3. #include<stdio.h>
   
4. #include<stdlib.h>
   
5. #include<sys/socket.h>
   
6. #include<netinet/in.h>
   
7. #include<linux/if_ether.h>
   
8. #include<signal.h>
   
9. #include<sys/types.h>
   
10. #include<linux/tcp.h>
    
11.   #include<linux/udp.h>
    
12. #include<linux/ip.h>
    
13. #include<unistd.h>
    
14. #include<signal.h>
    
15. #include<pthread.h>
    
16. #include<malloc.h>
    
17. 
    
18. #define STREAMSIZE 10000
    
19. #define BUFSIZE 2048
    
20. #define CACHESIZE 20
    
21. /*stream item info struct*/
    
22. typedef struct {
    
23.         unsigned short type;/*tcp or udp type */
    
24.         unsigned int sport;
    
25.         unsigned int dport;
    
26.         unsigned int sip;
    
27.         unsigned int dip;
    
28.         unsigned long count;
    
29.         unsigned long bytes;/*total bytes of a stream*/
    
30. }stream;
    
31. 
    
32. /*stream temp cache info struct*/
    
33. typedef struct {
    
34.         unsigned int type;
    
35.         unsigned int weight;
    
36.         unsigned int sport;
    
37.         unsigned int dport;
    
38.         unsigned int sip;
    
39.         unsigned int dip;
    
40. }cache_info;
    
41. 
    
42. cache_info cache_item[CACHESIZE];     /*streams last captured to make a queue*/
    
43. stream *item[STREAMSIZE];                 /*items are for stream info*/
    
44. int capture=1;
    
45. unsigned int item_max=0;                 /* current total items*/
    
46. unsigned int proto,sip,dip,sport,dport,ip_h_len,n_read=0;
    
47. 
    
48. void report()
    
49. {
    
50. int i=0,j;
    
51. char pro_type[3];
    
52. printf("    protocol\tsrc\t\tdest\t    sport  dport  packets\ttotal bytes\n");
    
53. for(i=1;i<=item_max;i++)
    
54. {
    
55. printf("\t%d\t%s\t%s  %d   %d   %d\t\t%d\n",item[i]->type,inet_ntoa(item[i]->sip),inet_ntoa(item[i]->dip),ntohs(item[i]->sport),ntohs(item[i]->dport),item[i]->count,item[i]->bytes);
    
56. }
    
57. 
    
58. 
    
59. }
    
60. void sig_handle(int signo)
    
61. {
    
62. capture=0;
    
63. report();
    
64. exit(1);
    
65. }
    
66. 
    
67. 
    
68. /*function for caching items that did not find in cache queue*/
    
69. void insert_cache_item()
    
70. {
    
71. printf("insert cache_item");
    
72. int i,id=11;
    
73. for(i=0;i<CACHESIZE;i++)
    
74. {
    
75. id=(id < cache_item[i].weight)? id : (cache_item[i].weight);
    
76. if(cache_item[i].weight==0)
    
77. {
    
78. cache_item[i].type=proto;
    
79. printf(" %d\n",i);
    
80. cache_item[i].sport=sport;
    
81. cache_item[i].dport=dport;
    
82. cache_item[i].sip=sip;
    
83. cache_item[i].dip=dip;
    
84. cache_item[i].weight+=2;
    
85. break;
    
86. }
    
87. }
    
88. if(id>0)                   /*in the cache_item,all weight is great than 0,but we
    
89.                            find the smallest weight is id,so cache_item[id]will be
    
90.                             recoverd by the new stream*/
    
91. {
    
92. printf(" %d\n",id);
    
93. cache_item[id].type=proto;
    
94. cache_item[id].sport=sport;
    
95. cache_item[id].dport=dport;
    
96. cache_item[id].sip=sip;
    
97. cache_item[id].dip=dip;
    
98. cache_item[id].weight=+1;
    
99. }
    
100. }
     
101. 
     
102. /*search the stream current captured in our cache_item.
     
103. the cache_item contains an item "weight" to record
     
104. how offen this stream being captured recently.when capture
     
105. a stream,first check it in cache_item,if find a match one,good,we
     
106. need not to search the big item array which contains all
     
107. stream items we captured before.
     
108. 
     
109. the algorithm of the weight is sample,weight is bettween 0-10,
     
110. when first insert into cache_item or the current captured stream
     
111. has been in cache_item,we add 2 to the stream weight.and at the
     
112. same time sub 1 to other stream item's weight.when the cache_item
     
113. is full,the item which has the smallest weight will be coverd.and
     
114. this is done by the insert_cache_item function*/
     
115. 
     
116. int search_cache_item()
     
117. {
     
118. int i,j=-1;
     
119. for(i=0;i<CACHESIZE;++i)
     
120. {
     
121. if(cache_item[i].type=proto&&cache_item[i].sport==sport&&cache_item[i].dport==dport&&cache_item[i].sip==sip&&cache_item[i].dip==dip)
     
122. {
     
123. if(cache_item[i].weight<=10)
     
124. {
     
125. cache_item[i].weight+=2;
     
126. }
     
127. j=i;
     
128. }/*we hava find one that match the current stream*/
     
129. else
     
130. {
     
131. if(cache_item[i].weight>=1)
     
132. cache_item[i].weight-=1;
     
133. }
     
134. }
     
135. printf("search_cache_item result is %d\n",j);
     
136. return j;
     
137. }
     
138. /*function to search the stream current captured
     
139. in the item[] which contains all the streams captured
     
140. before.*/
     
141. int search_item()
     
142. {
     
143. printf(" search in the item \n");
     
144. int i=0,j;
     
145. for(i=0;i<item_max;i++)
     
146. {
     
147. if(item[i]->sip==sip&&item[i]->sport==sport&&item[i]->dport==dport&&item[i]->type==proto&&item[i]->dip==dip)
     
148. {
     
149. item[i]->count+=1;
     
150. item[i]->bytes+=n_read;
     
151. break;
     
152. }
     
153. }
     
154. j=(i<item_max)? 1:-1;
     
155. printf("search in the item result is %d\n",j);
     
156. return j;
     
157. }
     
158. /*function to add the current stream captured to
     
159. the stream struct list*/
     
160. int add_to_item()
     
161. {
     
162. if(item_max<STREAMSIZE)
     
163. {
     
164. printf("item_max is %d\n",item_max);
     
165. item[item_max]=(stream *)(malloc(sizeof(stream)));
     
166. memset(item[item_max],0,sizeof(stream));
     
167. item[item_max]->type=proto;
     
168. item[item_max]->sip=sip;
     
169. item[item_max]->dip=dip;
     
170. item[item_max]->sport=sport;
     
171. item[item_max]->dport=dport;
     
172. item[item_max]->bytes+=n_read;
     
173. item[item_max]->count=+1;
     
174. item_max=item_max+1;
     
175. }
     
176. else
     
177. {
     
178. fprintf(stderr,"stream is to large please change the STREAMSIZE\n");
     
179. exit(1);
     
180. }
     
181. }
     
182. 
     
183. void main(int argc,char *argv[])
     
184. {
     
185. int i,ret,id,sockfd;
     
186. char buf[BUFSIZE];
     
187. struct tcphdr *tcp_head;
     
188. struct udphdr *udp_head;
     
189. struct iphdr *ip_head;
     
190. char *p;
     
191. 
     
192. for(i=0;i<CACHESIZE;i++)
     
193. {
     
194. cache_item[i].weight=0;
     
195. }
     
196. signal(SIGINT,sig_handle);
     
197. if((sockfd = socket(PF_PACKET,SOCK_RAW,htons(ETH_P_IP)))<0)
     
198. {
     
199.         fprintf(stderr,"socket error\n");
     
200.         printf("%d","sockfd");
     
201.         exit(1);
     
202. }
     
203. 
     
204. while(capture)
     
205. {
     
206. n_read = recvfrom(sockfd,buf,BUFSIZE,0,NULL,NULL);
     
207. ip_head = (struct iphdr *)(buf+14);
     
208. /*14=6 source mac address
     
209.      6 destnation mac address
     
210.      2 type
     
211. */
     
212. proto=ip_head->protocol;
     
213. sip=ip_head->saddr;
     
214. dip=ip_head->daddr;
     
215. ip_h_len=ip_head->ihl<<2;
     
216. if(proto==IPPROTO_TCP)
     
217. {
     
218. tcp_head = (struct tcphdr *)(buf+14+ip_h_len);
     
219. sport=tcp_head->source;
     
220. dport=tcp_head->dest;
     
221. if((id=search_cache_item())>=0)/*current stream is in cache*/
     
222. {
     
223. item[id]->count+=1;
     
224. item[id]->bytes+=n_read;
     
225. printf("use cache info\n");
     
226. }
     
227. else
     
228. {
     
229. insert_cache_item(); /*cache it */
     
230. if((ret=search_item())<0)
     
231. {
     
232. add_to_item();
     
233. }
     
234. }
     
235. }
     
236. else if(proto==IPPROTO_UDP)
     
237. {
     
238. udp_head=(struct udphdr *)(buf+14+ip_h_len);
     
239. sport=udp_head->source;
     
240. dport=udp_head->dest;
     
241. if(id=search_cache_item()>0)
     
242. {
     
243. item[id]->count+=1;
     
244. item[id]->bytes+=n_read;
     
245. }
     
246. else
     
247. {
     
248. insert_cache_item();
     
249. if(search_item()<0)
     
250. add_to_item();
     
251. }
     
252. }
     
253. }
     
254. }
     

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