那里能找到netstat的源代码阿？

newcmd

linux下的？
想要得到特定的tcp连接信息，分析/proc/net/tcp可以实现但是感觉自己写的效率不太高。
那位大虾指点一下。

王紫豪

1. 
   
2. /*
   
3. #-------------------------------------------------------------------------------
   
4. #                                                                                                                        
   
5. # $Id: netstat-nat.c,v 1.28 2005/01/29 15:24:37 mardan Exp $     
   
6. #      
   
7. # $Log: netstat-nat.c,v $
   
8. # Revision 1.28  2005/01/29 15:24:37  mardan
   
9. # Some cleanups, bumped to version 1.4.5
   
10. #
    
11. # Revision 1.27  2005/01/23 16:33:09  mardan
    
12. # Added protocol resolving
    
13. #
    
14. # Revision 1.26  2005/01/21 22:54:14  mardan
    
15. # Added some forgotten states
    
16. #
    
17. # Revision 1.25  2005/01/01 17:02:24  mardan
    
18. # Extraction of IPs and ports more dynamicly so it can be used with layer7 and
    
19. # maybe others when layout of ip_conntrack changes
    
20. # Added autoconf
    
21. #
    
22. # Revision 1.24  2003/09/01 20:36:52  mardan
    
23. # Fixed small bug which didn't allow to display hostnames in expanded mode,
    
24. # not enough bytes where allocated.
    
25. #
    
26. # Revision 1.23  2003/08/31 10:59:15  mardan
    
27. # Merged patch from Guomundur D. Haraldsson <gdh@binhex.EU.org> which does a
    
28. # more properly memory alloction and saver copies of variables.
    
29. # Changed versions to v1.4.3. Ready to release if found stable.
    
30. # Changed my e-mail to danny@tweegy.demon.nl
    
31. #
    
32. # Revision 1.22  2003/02/08 17:41:44  mardan
    
33. # made some last minor changes.
    
34. # ready to release v1.4.2
    
35. #
    
36. # Revision 1.21  2003/01/24 21:24:34  mardan
    
37. # Added unknown protocol, display as 'raw'
    
38. # Fixed hussle up in states when sorting connections
    
39. #
    
40. # Revision 1.20  2003/01/02 15:40:48  mardan
    
41. # Merged patch from Marceln, which removes unused variables, more understandable
    
42. # memory allocation error message, check to exit when there are no NAT connections
    
43. # and making netstat-nat compatible with uLibC.
    
44. # Updated files to v1.4.2
    
45. #
    
46. # Revision 1.19  2002/09/22 20:10:19  mardan
    
47. # Added '-v: print version'
    
48. # Added 'uninstall' to Makefile
    
49. # Updated all other files.
    
50. #
    
51. # Revision 1.18  2002/09/22 17:16:08  mardan
    
52. # Rewritten connection_table to allocate memory dynamicly.
    
53. #
    
54. # Revision 1.17  2002/09/12 19:32:12  mardan
    
55. # Added display local connections to NAT box self
    
56. # Updated README
    
57. # Small changes in Makefile
    
58. #
    
59. # Revision 1.16  2002/09/08 20:23:48  mardan
    
60. # Added sort by connection option. (source/destination IP/port)
    
61. # Updated README and man-page.
    
62. #
    
63. # Revision 1.15  2002/08/07 19:25:59  mardan
    
64. # Fixed bug, displayed wrong icmp connection in state REPLIED (dest was gateway).
    
65. #
    
66. # Revision 1.14  2002/08/07 19:02:54  mardan
    
67. # Fixed 'icmp' bug. Segmentation fault occured when displaying NATed icmp connections.
    
68. #
    
69. # Revision 1.13  2002/08/06 19:32:54  mardan
    
70. # Added small feature: no header output.
    
71. # Lots of code cleanup.
    
72. #
    
73. # Revision 1.12  2002/08/03 00:22:22  mardan
    
74. # Added portname resolving based on the listed names in 'services'.
    
75. # Re-arranged the layout.
    
76. # Added a Makefile and a header file.
    
77. # Updated the README.
    
78. #
    
79. # Revision 1.11  2002/07/12 20:05:54  mardan
    
80. # Added argument for extended view of hostnames.
    
81. # Moved display-code into one function.
    
82. # Removed most unnessacery code.
    
83. # Updated README
    
84. #
    
85. # Revision 1.10  2002/07/10 19:58:33  mardan
    
86. # Added filtering by destination-host, re-arranged some code to work properly.
    
87. # Tested DNAT icmp and udp.(pls report if any bugs occur)
    
88. # Fixed a few declaration bugs.
    
89. #
    
90. # Revision 1.9  2002/07/09 20:00:36  mardan
    
91. # Added fully DNAT support (udp & icmp not fully tested yet, but should work),
    
92. # including argument support for (S)(D)NAT selection.
    
93. # Re-arranged layout code, can possible merged into one function.
    
94. # Some few minor changes.
    
95. # Started to work on destination-host selection.
    
96. #
    
97. # Revision 1.8  2002/07/07 20:27:47  mardan
    
98. # Added display by source host/IP.
    
99. # Made a few fixes/changes.
    
100. # Updated the REAMDE.
     
101. #
     
102. # Revision 1.7  2002/06/30 19:55:41  mardan
     
103. # Added README and COPYING (license) FILES.
     
104. #
     
105. # Revision 1.6  2002/06/23 16:27:26  mardan
     
106. # Finished udp.
     
107. # Maybe some layout changes in future? therwise tool is finished.
     
108. #
     
109. # Revision 1.5  2002/06/23 14:07:46  mardan
     
110. # Added protocol arg option.
     
111. # Todo: udp protocol
     
112. #
     
113. # Revision 1.4  2002/06/23 12:57:35  mardan
     
114. # Added ident strings for test :-)
     
115. #
     
116. # Revision 1.3  2002/06/23 12:47:08  mardan
     
117. # Fixed resolved hostname hussle-up/layout
     
118. # Moved all source code into netstat-nat.c
     
119. #
     
120. # Revision 1.2  2002/06/23 11:56:09  mardan
     
121. # Added NAT icmp display.
     
122. # Still need to do udp (more states possible)
     
123. # Really need to fix resolved hostnames display, still hussled up.
     
124. #
     
125. # Revision 1.1.1.1  2002/05/04 01:08:06  mardan
     
126. # Initial import of netstat-nat, the C version.
     
127. # Array pointers really needs to be fixed, still lots of other bugs..
     
128. # So far only TCP displayed.
     
129. # No commandline args for e.g. no_nameresolving, protocol.
     
130. #
     
131. #
     
132. #                                                                                                                  
     
133. # Copyright (c) 2005 by D.Wijsman (danny@tweegy.demon.nl).
     
134. # All rights reserved.
     
135. #
     
136. # This program is free software; you can redistribute it and/or modify it
     
137. # under the terms of the GNU General Public License as published by the Free
     
138. # Software Foundation; either version 2 of the License, or (at your option)
     
139. # any later version.
     
140. #
     
141. # This program is distributed in the hope that it will be useful, but WITHOUT
     
142. # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
     
143. # FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
     
144. # more details.
     
145. #
     
146. # You should have received a copy of the GNU General Public License
     
147. # along with this program; see the file COPYING.  If not, write to
     
148. # the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
     
149. #               
     
150. #                                                                                                                        
     
151. #-------------------------------------------------------------------------------
     
152. */
     
153. 
     
154. #include "netstat-nat.h"
     
155. 
     
156. static char const rcsid[] = "$Id: netstat-nat.c,v 1.28 2005/01/29 15:24:37 mardan Exp $";
     
157. char SRC_IP[50];
     
158. char DST_IP[50];
     
159. int SNAT = 1;
     
160. int DNAT = 1;
     
161. int LOCAL = 0;
     
162. static char PROTOCOL[4];
     
163. int connection_index = 0;
     
164. char ***connection_table;
     
165. 
     
166. 
     
167. 
     
168. int main(int argc, char *argv[])
     
169.     {
     
170.     const char *args = "hnp:s:d:SDxor:L?v";
     
171.     static int SORT_ROW = 1;
     
172.     static int EXT_VIEW = 0;
     
173.     static int RESOLVE = 1;
     
174.     static int no_hdr = 0;
     
175.     FILE *f;
     
176.     char line[200];
     
177.     char src[50];
     
178.     char dst[50];
     
179.     char buf[100];
     
180.     char buf2[100];
     
181.     char from[50] = "NATed Address";
     
182.     char dest[50] = "Foreign Address";
     
183.    
     
184.     char ***pa;
     
185.     char *store;
     
186.     int index, a, b, c, j, r;
     
187.    
     
188.     connection_table = (char ***) xcalloc((1) * sizeof(char **));
     
189. 
     
190.     // check parameters
     
191.     while ((c = getopt(argc, argv, args)) != -1) {
     
192.         switch (c) {
     
193.         case 'h':
     
194.             display_help();
     
195.             return 1;
     
196.         case '?':
     
197.             display_help();
     
198.             return 1;
     
199.         case 'v':
     
200.             printf("Version %s\n", VERSION);
     
201.             return(0);
     
202.         case 'n':
     
203.             RESOLVE = 0;
     
204.             break;
     
205.         case 'p':
     
206.             strcopy(PROTOCOL, sizeof(PROTOCOL), optarg);
     
207.             break;
     
208.         case 's':
     
209.             strcopy(SRC_IP, sizeof(SRC_IP), optarg);
     
210.             lookup_ip(SRC_IP, sizeof(SRC_IP));
     
211.             break;
     
212.         case 'd':
     
213.             strcopy(DST_IP, sizeof(DST_IP), optarg);
     
214.             lookup_ip(DST_IP, sizeof(DST_IP));
     
215.             break;   
     
216.         case 'S':
     
217.             DNAT = 0;
     
218.             break;
     
219.         case 'D':
     
220.             SNAT = 0;
     
221.             break;
     
222.         case 'L':
     
223.             SNAT = 0;
     
224.             DNAT = 0;
     
225.             LOCAL = 1;
     
226.             break;
     
227.         case 'x':
     
228.             EXT_VIEW = 1;
     
229.             break;
     
230.         case 'o':
     
231.             no_hdr = 1;
     
232.             break;
     
233.         case 'r':
     
234.             if (optarg == NULL || optarg == '\0') {
     
235.                 display_help();
     
236.                 return 1;
     
237.                 }
     
238.             if (strcmp(optarg, "scr") == 0) SORT_ROW = 1; //default
     
239.             if (strcmp(optarg, "dst") == 0) SORT_ROW = 2;
     
240.             if (strcmp(optarg, "src-port") == 0) SORT_ROW = 3;
     
241.             if (strcmp(optarg, "dst-port") == 0) SORT_ROW = 4;
     
242.             if (strcmp(optarg, "state") == 0) SORT_ROW = 5;
     
243.             break;
     
244.         }
     
245.     }
     
246.    
     
247.     // some checking for IPTables and read file
     
248.     if ((f = fopen("/proc/net/ip_conntrack","r")) == NULL) {
     
249. //    if ((f = fopen("./conntrack.dump","r")) == NULL) {
     
250.         printf("Could not read info about connections from the kernel, make sure netfilter is enabled in kernel or by modules.\n");
     
251.         return 1;
     
252.         }
     
253.    
     
254.     // process conntrack table
     
255.     if (!no_hdr) {
     
256.         if (LOCAL) {
     
257.             strcopy(from, sizeof(from), "Source Address");
     
258.             strcopy(dest, sizeof(dest), "Destination Address");
     
259.             }
     
260.         if (!EXT_VIEW) {
     
261.             printf("%-6s%-31s%-31s%-6s\n", "Proto", from, dest, "State");
     
262.         } else {
     
263.             printf("%-6s%-41s%-41s%-6s\n", "Proto", from, dest, "State");
     
264.             }
     
265.         }
     
266. 
     
267.     while (fgets(line, sizeof(line), f) != NULL)
     
268.     {
     
269.         process_entry(line);
     
270.     }
     
271. 
     
272.     fclose(f);
     
273.    
     
274.     // create index of arrays pointed to main connection array
     
275.     if (connection_index == 0) {
     
276.         // There are no connections at this moment!
     
277.         return (0);
     
278.         }
     
279.    
     
280.     pa = (char ***) xcalloc((connection_index) * sizeof(char **));
     
281. 
     
282.     for (index = 0; index < connection_index; index++) {
     
283.         pa[index] = (char **) xcalloc((ROWS) * sizeof(char *));
     
284. 
     
285.         for (j = 0; j < ROWS; j++) {
     
286.             pa[index][j] = (char *) xcalloc(2);
     
287.             pa[index][j] = &connection_table[index][j][0];
     
288.             }
     
289.         }
     
290.     // sort by protocol and defined row
     
291.     for (a = 0; a < connection_index - 1; a++) {
     
292.         for (b = a + 1; b < connection_index; b++) {
     
293.             r = strcmp(pa[a][0], pa[b][0]);
     
294.             if (r > 0) {
     
295.                 for (j = 0; j < ROWS; j++) {
     
296.                     store = pa[a][j];
     
297.                     pa[a][j] = pa[b][j];
     
298.                     pa[b][j] = store;
     
299.                     }
     
300.                 }
     
301.             if (r == 0) {
     
302.                 if (strcmp(pa[a][SORT_ROW], pa[b][SORT_ROW]) > 0) {
     
303.                     for (j = 0; j < ROWS; j++) {
     
304.                         store = pa[a][j];
     
305.                         pa[a][j] = pa[b][j];
     
306.                         pa[b][j] = store;
     
307.                         }
     
308.                     }
     
309.                 }
     
310.             }
     
311.         }
     
312.     // print connections
     
313.     for (index = 0; index < connection_index; index++) {  
     
314.         if (RESOLVE) {
     
315.             lookup_hostname(&pa[index][1]);
     
316.             lookup_hostname(&pa[index][2]);
     
317.             if (strlen(pa[index][3]) > 0 || strlen(pa[index][4]) > 0) {
     
318.                 lookup_portname(&pa[index][3], pa[index][0]);
     
319.                 lookup_portname(&pa[index][4], pa[index][0]);
     
320.                     }
     
321.             }
     
322.         if (!EXT_VIEW) {
     
323.             strcopy(buf, sizeof(buf), "");
     
324.             strncat(buf, pa[index][1], 29 - strlen(pa[index][3]));   
     
325.             if (!strcmp(pa[index][0], "tcp") || !strcmp(pa[index][0], "udp")) {
     
326.                 snprintf(buf2, sizeof(buf2), "%s:%s", buf, pa[index][3]);            
     
327.             }
     
328.             else {
     
329.                 snprintf(buf2, sizeof(buf2), "%s", buf);
     
330.             }
     
331.             snprintf(src, sizeof(src),  "%-31s", buf2);
     
332.             strcopy(buf, sizeof(buf), "");
     
333.             strncat(buf, pa[index][2], 29 - strlen(pa[index][4]));   
     
334.             if (!strcmp(pa[index][0], "tcp") || !strcmp(pa[index][0], "udp")) {
     
335.                 snprintf(buf2, sizeof(buf2), "%s:%s", buf, pa[index][4]);            
     
336.             }
     
337.             else {
     
338.                 snprintf(buf2, sizeof(buf2), "%s", buf);
     
339.             }
     
340.             snprintf(dst, sizeof(dst), "%-31s", buf2);
     
341.         } else {
     
342.             strcopy(buf, sizeof(buf), "");
     
343.             strncat(buf, pa[index][1], 39 - strlen(pa[index][3]));   
     
344.             if (!strcmp(pa[index][0], "tcp") || !strcmp(pa[index][0], "udp")) {
     
345.                 snprintf(buf2, sizeof(buf2), "%s:%s", buf, pa[index][3]);
     
346.             }
     
347.             else {
     
348.                 snprintf(buf2, sizeof(buf2), "%s", buf);
     
349.             }
     
350.             snprintf(src , sizeof(src), "%-41s", buf2);
     
351.             strcopy(buf, sizeof(buf), "");
     
352.             strncat(buf, pa[index][2], 39 - strlen(pa[index][4]));   
     
353.             if (!strcmp(pa[index][0], "tcp") || !strcmp(pa[index][0], "udp")) {
     
354.                 snprintf(buf2, sizeof(buf2), "%s:%s", buf, pa[index][4]);
     
355.             }
     
356.             else {
     
357.                 snprintf(buf2, sizeof(buf2), "%s", buf);
     
358.             }
     
359.             snprintf(dst, sizeof(dst), "%-41s", buf2);
     
360.             }
     
361.         printf("%-6s%s%s%-11s\n", pa[index][0], src, dst, pa[index][5]);
     
362.         }
     
363.     return(0);
     
364.     }
     
365. 
     
366. // get protocol
     
367. int get_protocol(char *line, char *protocol)
     
368. {
     
369.     int i,j, protocol_nr;
     
370.     char protocol_name[10] = "";
     
371.     char protocol_raw[5] = "";
     
372.    
     
373.     if (string_search(line, "tcp")) {
     
374.         memcpy(protocol, "tcp", 3);
     
375.     }
     
376.     else if (string_search(line, "udp")) {
     
377.         memcpy(protocol, "udp", 3);
     
378.     }
     
379.     else if (string_search(line, "icmp")) {
     
380.         memcpy(protocol, "icmp", 4);
     
381.     }
     
382.     else {
     
383.         // here we search for protocol number and give it a name (get_protocol_name)
     
384.         for (i = 0; i < strlen(line); i++ ) {
     
385.             if(!strncmp(&line[i], "unknown  ", 9)) {
     
386.                 i += 9;
     
387.                 for (j = i; j < strlen(line); j++) {
     
388.                     if (line[j] == ' ') {
     
389.                         break;
     
390.                     }
     
391.                     strncat(protocol_raw, &line[j], 1);
     
392.                 }
     
393.                 protocol_nr = atoi(protocol_raw);
     
394.                 get_protocol_name(protocol_name, protocol_nr);
     
395.                 memcpy(protocol, protocol_name, 9);
     
396.                 break;
     
397.             }
     
398.         }
     
399.         //memcpy(protocol, "raw", 3);
     
400.     }
     
401. //    printf("PROTO: %s\n", protocol);
     
402.     return(0);
     
403. }
     
404. 
     
405. // get connection status
     
406. int get_connection_state(char *line, char *state)
     
407. {
     
408.     if (string_search(line, "ESTABLISHED")) {
     
409.         memcpy(state, "ESTABLISHED", 11);
     
410.     }
     
411.     else if (string_search(line, "TIME_WAIT")) {
     
412.         memcpy(state, "TIME_WAIT", 9);
     
413.     }   
     
414.     else if (string_search(line, "FIN_WAIT")) {
     
415.         memcpy(state, "FIN_WAIT", 8);
     
416.     }   
     
417.     else if (string_search(line, "SYN_RECV")) {
     
418.         memcpy(state, "SYN_RECV", 8);
     
419.     }   
     
420.     else if (string_search(line, "SYN_SENT")) {
     
421.         memcpy(state, "SYN_SENT", 8);
     
422.     }   
     
423.     else if (string_search(line, "UNREPLIED")) {
     
424.         memcpy(state, "UNREPLIED", 9);
     
425.     }   
     
426.     else if (string_search(line, "CLOSE")) {
     
427.         memcpy(state, "CLOSE", 5);
     
428.     }   
     
429.     else if (string_search(line, "ASSURED")) {
     
430.         memcpy(state, "ASSURED", 7);
     
431.     }
     
432.     else {
     
433.         if (string_search(line, "udp")) {
     
434.             memcpy(state, "UNREPLIED", 9);
     
435.         }
     
436.         else {
     
437.             memcpy(state, " ", 1);
     
438.         }
     
439.     }   
     
440. //    printf("STATE: %s\n", state);
     
441.     return(0);
     
442. }
     
443. 
     
444. void process_entry(char *line)
     
445. {
     
446.     int count;
     
447.     count = 0;
     
448.     char srcip_f[16] = "";
     
449.     char dstip_f[16] = "";
     
450.     char srcip_s[16] = "";
     
451.     char dstip_s[16] = "";
     
452.     char srcport[6] = "";
     
453.     char dstport[6] = "";
     
454.     char protocol[5] = "";
     
455.     char state[12] = "";
     
456. 
     
457.     search_first_hit("src=", line, srcip_f);   
     
458.     search_first_hit("dst=", line, dstip_f);   
     
459.     search_sec_hit("src=", line, srcip_s);   
     
460.     search_sec_hit("dst=", line, dstip_s);   
     
461.     search_first_hit("sport=", line, srcport);   
     
462.     search_first_hit("dport=", line, dstport);   
     
463. 
     
464.     get_protocol(line, protocol);
     
465.     if (strcmp(PROTOCOL, "")) {
     
466.         if (strncmp(PROTOCOL, protocol, 3)) {
     
467. //            printf("RETURN\n");
     
468.             return;
     
469.         }
     
470.     }
     
471.     get_connection_state(line, state);
     
472.     if (SNAT) {
     
473.         if ((!strcmp(srcip_f, dstip_s) == 0) && (strcmp(dstip_f, srcip_s) == 0)) {               
     
474.               check_src_dst(protocol, srcip_f, dstip_f, srcport, dstport, state);
     
475.             }
     
476.     }
     
477.     if (DNAT) {
     
478.         if ((strcmp(srcip_f, dstip_s) == 0) && (!strcmp(dstip_f, srcip_s) == 0)) {               
     
479.             check_src_dst(protocol, srcip_f, srcip_s, srcport, dstport, state);
     
480.         }
     
481.     }
     
482.     if (LOCAL) {
     
483.         if ((strcmp(srcip_f, dstip_s) == 0) && (strcmp(dstip_f, srcip_s) == 0)) {               
     
484.             check_src_dst(protocol, srcip_f, srcip_s, srcport, dstport, state);
     
485.         }
     
486.     }
     
487. //    printf("%s %s %s %s %s %s\n", protocol, srcip_f, dstip_f, srcip_s, dstip_s, state);
     
488. }
     
489. 
     
490. 
     

复制代码

王紫豪

1. 
   
2. // -- Internal used functions
   
3. // Check filtering by source and destination IP
   
4. void check_src_dst(char *protocol, char *src_ip, char *dst_ip, char *src_port, char *dst_port, char *status)
   
5.     {
   
6.     if ((check_if_source(src_ip)) && (strcmp(DST_IP, "") == 0)) {
   
7.         store_data(protocol, src_ip, dst_ip, src_port, dst_port, status);
   
8.         }
   
9.     else if ((check_if_destination(dst_ip)) && (strcmp(SRC_IP, "") == 0)) {
   
10.         store_data(protocol, src_ip, dst_ip, src_port, dst_port, status);
    
11.         }
    
12.     else if ((check_if_destination(dst_ip)) && (check_if_source(src_ip))) {
    
13.         store_data(protocol, src_ip, dst_ip, src_port, dst_port, status);
    
14.         }
    
15.     }
    
16. 
    
17. void store_data(char *protocol, char *src_ip, char *dst_ip, char *src_port, char *dst_port, char *status)  
    
18.     {
    
19.    
    
20.     connection_table = (char ***) xrealloc(connection_table, (connection_index +1) * sizeof(char **));
    
21.     connection_table[connection_index] = (char **) xcalloc(200 * sizeof(char *));
    
22.     connection_table[connection_index][0] = (char *) xcalloc(10);
    
23.     connection_table[connection_index][1] = (char *) xcalloc(60);
    
24.     connection_table[connection_index][2] = (char *) xcalloc(60);
    
25.     connection_table[connection_index][3] = (char *) xcalloc(20);
    
26.     connection_table[connection_index][4] = (char *) xcalloc(20);
    
27.     connection_table[connection_index][5] = (char *) xcalloc(15);
    
28.    
    
29.     strcopy(connection_table[connection_index][3], 20, src_port);
    
30.     strcopy(connection_table[connection_index][4], 20, dst_port);
    
31.     strcopy(connection_table[connection_index][1], 60, src_ip);
    
32.     strcopy(connection_table[connection_index][2], 60, dst_ip);
    
33.     strcopy(connection_table[connection_index][0], 10, protocol);
    
34.     strcopy(connection_table[connection_index][5], 15, status);
    
35.     connection_index++;
    
36.     }
    
37. 
    
38. void lookup_portname(char **port, char *proto)
    
39.     {
    
40.     char buf_port[10];
    
41.     int portnr;
    
42.     struct servent *service;
    
43.     size_t port_size;
    
44.    
    
45.     strcopy(buf_port, sizeof(buf_port), *port);
    
46.     portnr = htons(atoi(buf_port));
    
47.    
    
48.     if ((service = getservbyport(portnr, proto))) {
    
49.         port_size = strlen(service->s_name) + 8;
    
50.         *port = xrealloc(*port, port_size);
    
51.         strcopy(*port, port_size, service->s_name);
    
52.         }
    
53.     }
    
54. 
    
55. void extract_ip(char *gen_buffer)
    
56.     {
    
57.     char *split;
    
58.     split = strtok(gen_buffer, "=");
    
59.     split = strtok(NULL, "=");
    
60.     strcpy(gen_buffer, split);
    
61.     }
    
62. 
    
63. int lookup_hostname(char **r_host)
    
64.     {
    
65.     int addr;
    
66.     struct hostent *hp;
    
67.     char **p;
    
68.     size_t r_host_size;
    
69. 
    
70.     addr = inet_addr(*r_host);
    
71.     if ((hp = gethostbyaddr((char *) &addr, sizeof(addr), AF_INET)) == NULL)
    
72.         return 0;
    
73. 
    
74.     for (p = hp->h_addr_list; *p != 0; p++){
    
75.         struct in_addr in;
    
76.         (void)memcpy(&in.s_addr, *p, sizeof(in.s_addr));
    
77.         r_host_size = strlen(*r_host) + 25;
    
78.         *r_host = xrealloc(*r_host, r_host_size);       
    
79.         strcopy(*r_host, r_host_size, hp->h_name);
    
80.         }
    
81.     return 0;
    
82.     }
    
83. 
    
84. 
    
85. int lookup_ip(char *hostname, size_t hostname_size)
    
86.     {
    
87.     char *ip;
    
88.     struct hostent *hp;
    
89.     struct in_addr ip_addr;
    
90.    
    
91.     if ((hp = gethostbyname(hostname)) == NULL) {
    
92.         printf("Unknown host: %s\n", hostname);
    
93.         exit(-1);
    
94.         }
    
95. 
    
96.     ip_addr = *(struct in_addr *)(hp->h_addr);
    
97.     ip = inet_ntoa(*(struct in_addr *)(hp->h_addr));
    
98.     strcopy(hostname, hostname_size, ip);
    
99.     return 1;
    
100.     }
     
101. /*
     
102. int match(char *string, char *pattern)
     
103.     {
     
104.     int i;
     
105.     regex_t re;
     
106.     char buf[200];
     
107.    
     
108.     i = regcomp(&re, pattern, REG_EXTENDED|REG_NOSUB);
     
109. 
     
110.     if (i != 0) {
     
111.         (void)regerror(i, &re, buf, sizeof(buf));
     
112.         return 0;                       
     
113.         }
     
114.    
     
115.     i = regexec(&re, string, (size_t) 0, NULL, 0);
     
116.     regfree(&re);
     
117. 
     
118.     if (i != 0) {
     
119.         (void)regerror(i, &re, buf, sizeof(buf));
     
120.         return 0;                       
     
121.         }
     
122. 
     
123.     return 1;
     
124.     }
     
125. */
     
126. int check_if_source(char *host)
     
127.     {
     
128.     if ((strcmp(host, SRC_IP) == 0) || (strcmp(SRC_IP, "") == 0)) {
     
129.         return 1;
     
130.         }
     
131.     return 0;
     
132.     }
     
133. 
     
134. int check_if_destination(char *host)
     
135.     {
     
136.     if ((strcmp(host, DST_IP) == 0) || (strcmp(DST_IP, "") == 0)) {
     
137.         return 1;
     
138.         }
     
139.     return 0;
     
140.     }
     
141. 
     
142. 
     
143. static void *xcalloc(size_t bufsize)
     
144.     {
     
145.     void *buf;
     
146.        
     
147.     if ((buf = calloc(1, bufsize)) != NULL) {
     
148.         return buf;
     
149.     } else {
     
150.         printf("Could not allocate memory (%i bytes); %s.\n -- Exiting.\n", bufsize, strerror(errno));
     
151.         exit(1);
     
152.         }
     
153.     }
     
154. 
     
155. 
     
156. static void *xrealloc(void *oldbuf, size_t newbufsize)
     
157.     {
     
158.     void *newbuf;
     
159.        
     
160.     if ((newbuf = realloc(oldbuf, newbufsize)) != NULL) {
     
161.         return newbuf;
     
162.     } else {
     
163.         printf("Could not allocate memory (%i bytes); %s.\n -- Exiting.\n", newbufsize, strerror(errno));
     
164.         exit(1);
     
165.         }
     
166.     }
     
167. 
     
168. 
     
169. int string_search(char *string, char *search)
     
170. {
     
171.     int searchLen;
     
172.     int i;
     
173.     searchLen = strlen(search);
     
174.     if (searchLen > strlen(string)) {
     
175.         return(0); // this can't match
     
176.     }
     
177.     for (i = 0; i < strlen(string) - searchLen + 1; i++) {
     
178.         if (!strncasecmp((char *)&string[i], search, searchLen)) {
     
179.             return(1); // we got hit
     
180.         }
     
181.     }
     
182.     return(0);
     
183. }
     
184. 
     
185. 
     
186. int search_first_hit(char *search, char *line, char *ret)
     
187. {
     
188.     unsigned int searchLen;
     
189.     unsigned int i;
     
190.     unsigned int j;
     
191.     unsigned int lineLen;
     
192.    
     
193.     lineLen = strlen(line);
     
194.     searchLen = strlen(search);
     
195. 
     
196.     if (searchLen > lineLen) {
     
197.         return(1); // this can't match, invalid data?
     
198.     }
     
199.     for (i = 0; i < lineLen - searchLen + 1; i++) {
     
200.         if (!strncasecmp((char *)&line[i], search, searchLen)) {
     
201.             break; // we got hit
     
202.         }
     
203.     }
     
204.     for (j = i + searchLen; j < i + 15 + searchLen; j++) {
     
205.         if (j > lineLen) {
     
206.             return(1); // incomplete data
     
207.         }
     
208.         if (line[j] == ' ') {
     
209.             break; // we reach _space_ delimiter
     
210.         }
     
211.     }
     
212.     memcpy(ret, &line[i + searchLen], j - i - searchLen);
     
213.     return(0);
     
214. }
     
215. 
     
216. 
     
217. int search_sec_hit(char *search, char *line, char *ret)
     
218. {
     
219.     unsigned int searchLen;
     
220.     unsigned int i;
     
221.     unsigned int j;
     
222.     unsigned int got_first = 0;
     
223.     unsigned int lineLen;
     
224.    
     
225.     lineLen = strlen(line);
     
226.     searchLen = strlen(search);
     
227. 
     
228.     if (searchLen > lineLen) {
     
229.         return(1); // this can't match, invalid data?
     
230.     }
     
231.     for (i = 0; i < lineLen - searchLen + 1; i++) {
     
232.         if (!strncasecmp((char *)&line[i], search, searchLen)) {
     
233.             if (got_first) {
     
234.                 break; // we got hit (second)
     
235.             }
     
236.             got_first = 1;
     
237.         }
     
238.     }
     
239.     for (j = i + searchLen; j < i + 15 + searchLen; j++) {
     
240.         if (j > lineLen) {
     
241.             return(1); // incomplete data
     
242.         }
     
243.         if (line[j] == ' ') {
     
244.             break; // we reach _space_ delimiter
     
245.         }
     
246.     }
     
247.     memcpy(ret, &line[i + searchLen], j - i - searchLen);
     
248.     return(0);
     
249. }
     
250. 
     
251. 
     
252. void get_protocol_name(char *protocol_name, int protocol_nr)
     
253. {
     
254.     struct protoent *proto_struct;
     
255.     char strconvers[10] = "";
     
256.     proto_struct = getprotobynumber(protocol_nr);
     
257.     if (proto_struct != NULL) {
     
258.         memcpy(protocol_name, proto_struct->p_name, 5);
     
259.     }
     
260.     else {
     
261.         snprintf(strconvers, 6, "%d", protocol_nr);
     
262.         memcpy(protocol_name, strconvers, 5);
     
263.     }
     
264. }
     
265. 
     
266. 
     
267. void display_help()
     
268.     {
     
269.     printf("args: -h: displays this help\n");
     
270.     printf("      -n: don't resolve host/portnames\n");
     
271.     printf("      -p <protocol>        : display connections by protocol\n");
     
272.     printf("      -s <source-host>     : display connections by source\n");
     
273.     printf("      -d <destination-host>: display connections by destination\n");
     
274.     printf("      -S: display SNAT connections\n");
     
275.     printf("      -D: display DNAT connections (default: SNAT & DNAT)\n");
     
276.     printf("      -L: display only connections to NAT box itself (doesn't show SNAT & DNAT)\n");
     
277.     printf("      -x: extended hostnames view\n");
     
278.     printf("      -r src | dst | src-port | dst-port | state : sort connections\n");
     
279.     printf("      -o: strip output header\n");
     
280.     printf("      -v: print version\n");
     
281.     }
     
282. 
     
283. // -- End of internal used functions
     
284. 
     
285. // -- The End --
     

复制代码

王紫豪

下面是头文件

1. 
   
2. /*
   
3. #-------------------------------------------------------------------------------
   
4. #                                                                                                                        
   
5. # $Id: netstat-nat.h,v 1.11 2005/01/29 15:24:37 mardan Exp $     
   
6. #      
   
7. #                                                                                                                  
   
8. # Copyright (c) 2005 by D.Wijsman (danny@tweegy.demon.nl).
   
9. # All rights reserved.
   
10. #
    
11. # This program is free software; you can redistribute it and/or modify it
    
12. # under the terms of the GNU General Public License as published by the Free
    
13. # Software Foundation; either version 2 of the License, or (at your option)
    
14. # any later version.
    
15. #
    
16. # This program is distributed in the hope that it will be useful, but WITHOUT
    
17. # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    
18. # FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
    
19. # more details.
    
20. #
    
21. # You should have received a copy of the GNU General Public License
    
22. # along with this program; see the file COPYING.  If not, write to
    
23. # the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
    
24. #               
    
25. #                                                                                                                        
    
26. #-------------------------------------------------------------------------------
    
27. */
    
28. 
    
29. #include <stdio.h>
    
30. #include <stdlib.h>
    
31. #include <string.h>
    
32. //#include <regex.h>
    
33. #include <netdb.h>
    
34. #include <unistd.h>
    
35. #include <arpa/inet.h>
    
36. #include <errno.h>
    
37. #include <strings.h>
    
38. 
    
39. //#define VERSION                "1.4.4"
    
40. #define ROWS                6
    
41. 
    
42. 
    
43. int get_protocol(char *line, char *protocol);
    
44. int get_connection_state(char *line, char *state);
    
45. void process_entry(char *line);
    
46. void check_src_dst(char *protocol, char *src_ip, char *dst_ip, char *src_port, char *dst_port, char *status);
    
47. void store_data(char *protocol, char *src_ip, char *dst_ip, char *src_port, char *dst_port, char *status);
    
48. void extract_ip(char *gen_buffer);
    
49. void display_help();
    
50. int lookup_hostname(char **r_host);
    
51. int lookup_ip(char *hostname, size_t hostname_size);
    
52. //int match(char *string, char *pattern);
    
53. int check_if_source(char *host);
    
54. int check_if_destination(char *host);
    
55. void lookup_portname(char **port, char *proto);
    
56. void oopsy(int size);
    
57. static void *xrealloc(void *oldbuf, size_t newbufsize);
    
58. static void *xcalloc(size_t bufsize);
    
59. void get_protocol_name(char *protocol_name, int protocol_nr);
    
60. 
    
61. #define strcopy(dst, dst_size, src) \
    
62.         strncpy(dst, src, (dst_size - 1));
    
63. 
    
64. /* The End */
    

复制代码

newcmd

感谢！！！我从freshmeat看到了这个源码，它只是显示nat的连接信息所以没看，不过到是有一定的参考价值，但是/proc/net/tcp的数据看着不大一样，有没分析这个文件的代码阿？

DirtyBear

看这个：
http://www.busybox.net/cgi-bin/v ... busybox/networking/
这个网站比较有意思，主要是为嵌入式操作系统改写linux上的一些软件，变小、变巧。这样有利于我们学习这些工具的基本原理。

duanjigang

原帖由 newcmd 于 2006-7-6 23:25 发表
感谢！！！我从freshmeat看到了这个源码，它只是显示nat的连接信息所以没看，不过到是有一定的参考价值，但是/proc/net/tcp的数据看着不大一样，有没分析这个文件的代码阿？

Linux下的net-tools中的netstat命令就是通过分析proc文件系统实现的，我根据源码写了一个端口扫描的程序(IPV4 & IPV6)，你可以参考下
http://linux.chinaunix.net/bbs/viewthread.php?tid=864757
再给你附上net-tools的源码吧，其中就有netstat route 等命令的源码

[ 本帖最后由 duanjigang 于 2007-8-1 09:15 编辑 ]

yuangong

楼上的头像看的心里老不爽了,干嘛搞这么吓人的?

MMMIX

原帖由 yuangong 于 2007-8-1 09:23 发表
楼上的头像看的心里老不爽了,干嘛搞这么吓人的?

直接在设置里面选择不显示头像，你就啥也看不到了

duanjigang

原帖由 yuangong 于 2007-8-1 09:23 发表
楼上的头像看的心里老不爽了,干嘛搞这么吓人的?

女人这样的眼神多有气质啊，呵呵
要懂得欣赏