2 * hdw-sniff, sniffer using pcap lib
4 * author: hackbard@hackdaworld.dyndns.org
10 #include <sys/socket.h>
12 #include <netinet/in.h>
13 #include <arpa/inet.h>
15 #include <sys/types.h>
19 #include <sys/ioctl.h>
21 /* IEEE 802.3 stuff -- i will concentrate on .11 stuff before! */
22 #include <netinet/if_ether.h> /* for ethhdr struct */
23 #include <netinet/ip.h> /* ip */
24 #include <netinet/in.h> /* in_addr , inet_ntoa */
26 /* IEEE 802.11 stuff -- will become one include later ... */
27 #include "ieee80211.h" /* from hunz's aeolus, short hostap_wlan.h */
28 #include "ieee802_11.h" /* from pcmcia-cs */
30 #include "hdw-sniff.h" /* my functions */
32 /* global variables */
35 int main(int argc, char *argv[]) {
37 char pcap_error[PCAP_ERRBUF_SIZE];
41 struct timeval fd_set_tv;
43 struct info_struct my_info_struct;
45 /* parse the arguments */
47 printf("usage: %s <interface> <monitor mode> <logfile>\n",
52 printf("no logfile specified, writing to stdout ...\n");
55 if((file_fd=open(argv[3],O_RDWR | O_CREAT))!=0) {
56 printf("writing to logfile %s ...\n",argv[3]);
57 dprintf(file_fd,"|iv - --|id|crypted_snap - --|\n");
60 printf("can't open logfile. not logged to file!\n");
64 /* setting up device and set monitor mode */
65 if(atoi(argv[2])==1) {
66 printf("setting to monitor mode\n");
67 if(strncmp(argv[1],"wlan",4)==0)
68 sprintf(sys_call,"iwpriv %s monitor 3",argv[1]);
69 if(strncmp(argv[1],"eth",3)==0)
70 sprintf(sys_call,"ifconfig %s promisc",argv[1]);
73 printf("setting up interface\n");
74 sprintf(sys_call,"ifconfig %s up",argv[1]);
77 /* start pcap session */
78 pcap_handle=pcap_open_live(argv[1],BUFSIZ,1,-1,pcap_error);
79 if(pcap_handle==NULL) {
80 printf("%s: %s\n",argv[0],pcap_error);
84 /* set non blocking */
85 if((pcap_setnonblock(pcap_handle,1,pcap_error))==-1) {
86 printf("%s: %s\n",argv[0],pcap_error);
91 my_info_struct.count=0;
92 my_info_struct.mmode=argv[2][0];
93 my_info_struct.ssid_list=(struct list *)malloc(sizeof(struct list));
94 my_info_struct.ssid_list->next=NULL;
95 // strcpy(my_info_struct.ssid_list->ssid,"test");
96 strcpy(my_info_struct.dev,argv[1]);
98 /* prepare for select */
99 pcap_fd=pcap_fileno(pcap_handle);
101 /* create file descriptor */
102 if((foo_fd=socket(AF_INET,SOCK_DGRAM,0))==-1) {
103 printf("unable to create socket foo_fd\n");
111 FD_ZERO(&pcap_fd_set);
112 FD_SET(pcap_fd,&pcap_fd_set);
114 fd_set_tv.tv_usec=200000;
116 if((select(pcap_fd+1,&pcap_fd_set,NULL,NULL,&fd_set_tv)) && (FD_ISSET(pcap_fd,&pcap_fd_set))) pcap_dispatch(pcap_handle,-1,pcap_process,(u_char *)&my_info_struct);
117 else if((hop_channel(&my_info_struct,foo_fd))==-1) {
118 printf("channelhopping failed, aborting\n");
126 /* pcap_process callback function */
127 void pcap_process(u_char *info,const struct pcap_pkthdr *pcap_header,
128 const u_char *package) {
130 /* local variables */
131 char tmp_buf[20],tmp_buf1[10],tmp_buf2[32];
132 unsigned char crypted_snap[12];
133 struct linux_wlan_ng_prism_hdr *prism_hdr;
134 struct ieee802_11_hdr *w_hdr;
135 struct snaphdr *snap_hdr;
136 struct beacon_struct *beacon_hdr;
137 struct ethhdr *e_hdr;
138 struct info_struct *my_info_struct;
139 int i,p_o,w_o,e_o,i_o;
141 my_info_struct=(struct info_struct *)info;
142 ++(my_info_struct->count);
145 p_o=((strncmp(my_info_struct->dev,"wlan",4)==0)?sizeof(struct linux_wlan_ng_prism_hdr):0);
146 w_o=((strncmp(my_info_struct->dev,"wlan",4)==0)?sizeof(struct ieee802_11_hdr):0);
147 e_o=sizeof(struct ethhdr);
148 i_o=sizeof(struct iphdr);
152 printf("---> package %d ---- %s",my_info_struct->count,
153 ctime((const time_t*)&(pcap_header->ts.tv_sec)));
156 printf("pcap header: ");
157 printf("capture_length(dec): %d\t",pcap_header->caplen);
158 printf("off_wire_length(dec): %d\n",pcap_header->len);
161 /* prism wlan ng headers */
162 if((my_info_struct->mmode-0x30==1) &
163 (strncmp(my_info_struct->dev,"wlan",4)==0)) {
164 printf("prism header: (%d bytes)\n",p_o);
165 prism_hdr=(struct linux_wlan_ng_prism_hdr *)package;
166 printf("| message code/length: %d/%d |\t",prism_hdr->msgcode,
168 printf("device: %s |\n",prism_hdr->devname);
169 /* ieee802.11 header */
171 /* we need smaller w_hdr for non distributed frames */
172 if((w_hdr->frame_ctl & (1<<8)) & (w_hdr->frame_ctl & (1<<9))) {
173 printf("=> distributed packet !!!!11\n");
174 } else w_o-=(sizeof(struct snaphdr)-sizeof(unsigned short));
176 printf("ieee802.11 header: (%d bytes)\n",w_o);
177 w_hdr=(struct ieee802_11_hdr *)(package+p_o);
181 printf("%s%d%s",(i==0?"|":""),
182 (((w_hdr->frame_ctl) & (1<<i))>0?1:0),
184 printf(" | v | t | s-t |t|f|m|r|p|m|w|o|\n");
187 if(!(w_hdr->frame_ctl & 0x0c)) {
188 tmp_buf1[0]='\0'; tmp_buf2[0]='\0';
189 if((w_hdr->frame_ctl & IEEE802_11_STYPE_ASSOC_REQ)>0)
190 strcpy(tmp_buf,"association request");
191 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_ASSOC_RESP)>0)
192 strcpy(tmp_buf,"association response");
193 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_REASSOC_REQ)>0)
194 strcpy(tmp_buf,"reassociation request");
195 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_REASSOC_RESP)>0)
196 strcpy(tmp_buf,"reassociation response");
197 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_PROBE_REQ)>0)
198 strcpy(tmp_buf,"probe request");
199 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_PROBE_RESP)>0)
200 strcpy(tmp_buf,"probe response");
201 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_BEACON)==IEEE802_11_STYPE_BEACON) {
202 beacon_hdr=(struct beacon_struct *)(package+p_o+w_o);
203 beacon_hdr->ssid_s.elementid==0?strcpy(tmp_buf1,"essid = ")
204 :strcpy(tmp_buf1,"ibssid = ");
205 strncpy(tmp_buf2,beacon_hdr->ssid_s.ssid,
206 beacon_hdr->ssid_s.length);
207 tmp_buf2[beacon_hdr->ssid_s.length]='\0';
208 strcpy(tmp_buf,"beacon");
209 add_ssid_2_list(tmp_buf2,my_info_struct->ssid_list);
211 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_ATIM)>0)
212 strcpy(tmp_buf,"announcement traffic indication message");
213 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_DISASSOC)>0)
214 strcpy(tmp_buf,"disassociation");
215 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_AUTH)>0)
216 strcpy(tmp_buf,"authentification");
217 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_DEAUTH)>0)
218 strcpy(tmp_buf,"deauthentification");
219 else strcpy(tmp_buf,"impossible situation \%) - go mail the author.");
221 else strcpy(tmp_buf,"control or data frame type");
223 printf("=> %s\n",tmp_buf);
224 if(strlen(tmp_buf1)>0 & strlen(tmp_buf2)>0) printf(" %s%s\n",
227 printf("duration/id: 0x%x\n",w_hdr->duration_id);
228 printf("version check ... %s\n",
229 ((w_hdr->frame_ctl & IEEE802_11_FCTL_VERS)==0x00)?
234 if((strncmp(my_info_struct->dev,"eth",3)==0) |
235 ((w_hdr->frame_ctl & IEEE802_11_FTYPE_DATA)==IEEE802_11_FTYPE_DATA)) {
237 if((strncmp(my_info_struct->dev,"eth",3)==0)) {
238 printf("ethernet: (%d bytes)\n",e_o);
239 e_hdr=(struct ethhdr *)(package+p_o+w_o);
242 printf("%x ",ntohs(e_hdr->h_proto));
243 printf("dest_addr = ");
244 for(i=0;i<ETH_ALEN;i++)
245 printf("%x%s",*(e_hdr->h_dest+i),((i==ETH_ALEN-1)?" ":":"));
246 printf(" src_addr = ");
247 for(i=0;i<ETH_ALEN;i++) printf("%x%s",*(e_hdr->h_source+i),
248 ((i==ETH_ALEN-1)?"\n":":"));
249 if((ntohs(e_hdr->h_proto)==ETH_P_IP))
250 parse_ip(package+p_o+w_o+e_o);
253 snap_hdr=(struct snaphdr *)(package+p_o+w_o);
254 if((snap_hdr->snap[0]==0xaa) &
255 (snap_hdr->snap[1]==0xaa) &
256 (snap_hdr->snap[2]==0x03) &
257 (snap_hdr->snap[3]==0x00) &
258 (snap_hdr->snap[4]==0x00) &
259 (snap_hdr->snap[5]==0x00)) {
260 printf("- no encryption!\n");
261 if(snap_hdr->proto==ntohs(ETH_P_IP)) {
262 e_o=sizeof(struct snaphdr);
263 parse_ip(snap_hdr+e_o);
268 printf("- crypted packet!\n");
269 /* print crypted snap - write into file */
270 printf("snap: (iv(3) + index(1) + crypted snap(6)) ");
272 printf("%x ",*(snap_hdr->snap+i));
273 crypted_snap[i]=*(snap_hdr->snap+i);
276 crypted_snap[4]^=0xaa;
277 crypted_snap[5]^=0xaa;
278 crypted_snap[6]^=0x03;
279 crypted_snap[7]^=0x00;
280 crypted_snap[8]^=0x00;
281 crypted_snap[9]^=0x00;
285 crypted_snap[10]='\0';
286 crypted_snap[11]='\n';
289 printf("debug: saved to file\n");
290 dprintf(file_fd,IVLINE,IVL_ARGS);
298 printf("all dump: (hex)\n");
299 for(i=p_o+w_o;i<pcap_header->caplen;i++)
300 printf("%x ",*(package+i));
304 printf("all dump: (char)\n");
305 for(i=p_o+w_o;i<pcap_header->caplen;i++)
306 printf("%c ",*(package+i));
311 int hop_channel(struct info_struct *info,int foo_fd) {
312 if((info->mmode-0x30==1) && (strncmp(info->dev,"wlan",4)==0)) {
314 struct iwreq my_iwreq;
316 if (info->channel>=C_MAX) info->channel=1;
318 memset(&my_iwreq,0,sizeof(my_iwreq));
319 strcpy(my_iwreq.ifr_name,info->dev);
321 my_iwreq.u.freq.m=info->channel;
322 if((ioctl(foo_fd,SIOCSIWFREQ,&my_iwreq))==-1) {
323 printf("unable to hop channels\n");
332 int parse_ip(char *ip_o) {
333 struct iphdr *ip_hdr;
336 printf("ip protocol:\n");
337 ip_hdr=(struct iphdr *)ip_o;
338 printf("version = %x ",ntohs(ip_hdr->version));
339 printf("header_length = %x \n",ntohs(ip_hdr->ihl));
340 printf("service = %x ",ntohs(ip_hdr->tos));
341 printf("total_length(dec.) = %d \n",ntohs(ip_hdr->tot_len));
342 printf("source_ip: ");
345 (ip_hdr->saddr&(0xff<<(8*i)))>>(8*i),
348 printf("destination_ip: ");
351 (ip_hdr->daddr&(0xff<<(8*i)))>>(8*i),
354 printf("ip_id = %x ",ntohs(ip_hdr->id));
355 printf("ip_offset = %x \n",ntohs(ip_hdr->frag_off));
356 printf("time2live = %x ip_proto = %x\n",ntohs(ip_hdr->ttl),
357 ntohs(ip_hdr->protocol));
358 // printf("chksum: %x\n",ntohs(ip_hdr->ip_sum));