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]);
59 printf("can't open logfile!\n");
63 /* setting up device and set monitor mode */
64 if(atoi(argv[2])==1) {
65 printf("setting to monitor mode\n");
66 if(strncmp(argv[1],"wlan",4)==0)
67 sprintf(sys_call,"iwpriv %s monitor 3",argv[1]);
68 if(strncmp(argv[1],"eth",3)==0)
69 sprintf(sys_call,"ifconfig %s promisc",argv[1]);
72 printf("setting up interface\n");
73 sprintf(sys_call,"ifconfig %s up",argv[1]);
76 /* start pcap session */
77 pcap_handle=pcap_open_live(argv[1],BUFSIZ,1,-1,pcap_error);
78 if(pcap_handle==NULL) {
79 printf("%s: %s\n",argv[0],pcap_error);
83 /* set non blocking */
84 if((pcap_setnonblock(pcap_handle,1,pcap_error))==-1) {
85 printf("%s: %s\n",argv[0],pcap_error);
89 /* grab a package until user breaks */
90 my_info_struct.count=0;
91 my_info_struct.mmode=argv[2][0];
92 strcpy(my_info_struct.dev,argv[1]);
94 /* prepare for select */
95 pcap_fd=pcap_fileno(pcap_handle);
97 /* create file descriptor */
98 if((foo_fd=socket(AF_INET,SOCK_DGRAM,0))==-1) {
99 printf("unable to create socket foo_fd\n");
107 FD_ZERO(&pcap_fd_set);
108 FD_SET(pcap_fd,&pcap_fd_set);
110 fd_set_tv.tv_usec=200000;
112 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);
113 else if((hop_channel(&my_info_struct,foo_fd))==-1) {
114 printf("channelhopping failed, aborting\n");
122 /* pcap_process callback function */
123 void pcap_process(u_char *info,const struct pcap_pkthdr *pcap_header,
124 const u_char *package) {
126 /* local variables */
127 char tmp_buf[20],crypted_snap[11];
128 struct linux_wlan_ng_prism_hdr *prism_hdr;
129 struct ieee802_11_hdr *w_hdr;
130 struct snaphdr *snap_hdr;
131 struct ethhdr *e_hdr;
132 struct iphdr *ip_hdr;
133 struct info_struct *my_info_struct;
134 int i,p_o,w_o,e_o,i_o;
136 my_info_struct=(struct info_struct *)info;
137 ++(my_info_struct->count);
140 p_o=((strncmp(my_info_struct->dev,"wlan",4)==0)?sizeof(struct linux_wlan_ng_prism_hdr):0);
141 w_o=((strncmp(my_info_struct->dev,"wlan",4)==0)?sizeof(struct ieee802_11_hdr):0);
142 e_o=sizeof(struct ethhdr);
143 i_o=sizeof(struct iphdr);
147 printf("---> package %d ---- %s",my_info_struct->count,
148 ctime((const time_t*)&(pcap_header->ts.tv_sec)));
151 printf("pcap header: ");
152 printf("capture_length(dec): %d\t",pcap_header->caplen);
153 printf("off_wire_length(dec): %d\n",pcap_header->len);
156 /* prism wlan ng headers */
157 if((my_info_struct->mmode-0x30==1) &&
158 (strncmp(my_info_struct->dev,"wlan",4)==0)) {
159 printf("prism header: (%d bytes)\n",p_o);
160 prism_hdr=(struct linux_wlan_ng_prism_hdr *)package;
161 printf("| message code/length: %d/%d |\t",prism_hdr->msgcode,
163 printf("device: %s |\n",prism_hdr->devname);
164 /* ieee802.11 header */
165 printf("ieee802.11 header: (%d bytes)\n",w_o);
166 w_hdr=(struct ieee802_11_hdr *)(package+p_o);
170 printf("%s%d%s",(i==0?"|":""),
171 (((w_hdr->frame_ctl) & (1<<i))>0?1:0),
173 printf(" | v | t | s-t |t|f|m|r|p|m|w|o|\n");
176 if(!(w_hdr->frame_ctl & 0x0c)) {
177 if((w_hdr->frame_ctl & IEEE802_11_STYPE_ASSOC_REQ)>0)
178 strcpy(tmp_buf,"association request");
179 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_ASSOC_RESP)>0)
180 strcpy(tmp_buf,"association response");
181 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_REASSOC_REQ)>0)
182 strcpy(tmp_buf,"reassociation request");
183 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_REASSOC_RESP)>0)
184 strcpy(tmp_buf,"reassociation response");
185 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_PROBE_REQ)>0)
186 strcpy(tmp_buf,"probe request");
187 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_PROBE_RESP)>0)
188 strcpy(tmp_buf,"probe response");
189 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_BEACON)>0)
190 strcpy(tmp_buf,"beacon");
191 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_ATIM)>0)
192 strcpy(tmp_buf,"announcement traffic indication message");
193 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_DISASSOC)>0)
194 strcpy(tmp_buf,"disassociation");
195 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_AUTH)>0)
196 strcpy(tmp_buf,"authentification");
197 else if((w_hdr->frame_ctl & IEEE802_11_STYPE_DEAUTH)>0)
198 strcpy(tmp_buf,"deauthentification");
199 else strcpy(tmp_buf,"impossible situation \%) - go mail the author.");
201 else strcpy(tmp_buf,"control & data frame type not supported yet");
202 /* print out frame type */
203 printf("=> %s\n",tmp_buf);
205 printf("duration/id: 0x%x\n",w_hdr->duration_id);
206 printf("version check ... %s\n",
207 ((w_hdr->frame_ctl & IEEE802_11_FCTL_VERS)==0x00)?
212 /* we need smaller w_hdr for non distributed frames */
213 if((w_hdr->frame_ctl & (1<<8)) & (w_hdr->frame_ctl & (1<<9))) {
214 printf("=> distributed packet !!!!11\n");
215 } else w_o-=(sizeof(struct snaphdr)-sizeof(unsigned short));
218 if((strncmp(my_info_struct->dev,"eth",3)==0) |
219 ((w_hdr->frame_ctl & IEEE802_11_FTYPE_DATA)>0)) {
221 if(!(w_hdr->frame_ctl & IEEE802_11_FTYPE_DATA)) {
222 printf("ethernet: (%d bytes)\n",e_o);
223 e_hdr=(struct ethhdr *)(package+p_o+w_o);
226 printf("%x ",ntohs(e_hdr->h_proto));
227 printf("dest_addr = ");
228 for(i=0;i<ETH_ALEN;i++)
229 printf("%x%s",*(e_hdr->h_dest+i),((i==ETH_ALEN-1)?" ":":"));
230 printf(" src_addr = ");
231 for(i=0;i<ETH_ALEN;i++) printf("%x%s",*(e_hdr->h_source+i),
232 ((i==ETH_ALEN-1)?"\n":":"));
235 snap_hdr=(struct snaphdr *)(package+p_o+w_o);
236 if((snap_hdr->snap[0]==0xaa) &
237 (snap_hdr->snap[1]==0xaa) &
238 (snap_hdr->snap[2]==0x03) &
239 (snap_hdr->snap[3]==0x00) &
240 (snap_hdr->snap[4]==0x00) &
241 (snap_hdr->snap[5]==0x00)) {
242 printf("- no encryption!\n");
243 if(snap_hdr->proto==ntohs(ETH_P_IP)) {
244 /* we want ip header to get parsed */
245 e_hdr->h_proto=htons(ETH_P_IP);
246 e_o=sizeof(struct snaphdr);
250 printf("- crypted packet!\n");
251 /* print crypted snap - write into file */
252 printf("snap: (aa aa 03 00 00 00) ");
254 printf("%x ",*(snap_hdr->snap-4+i));
255 crypted_snap[i]=*(snap_hdr->snap-4+i);
257 // write(file_fd,snap_hdr->snap+i-4,1);
261 printf("%x ",snap_hdr->snap[i]);
262 crypted_snap[4+i]=snap_hdr->snap[i];
264 // write(file_fd,snap_hdr->snap+i,1);
267 crypted_snap[10]='\n';
269 printf("debug: saved to file\n");
270 write(file_fd,crypted_snap,11);
272 /* dont look at ipheader */
273 e_hdr->h_proto=htons(0);
278 if(ntohs(e_hdr->h_proto)==ETH_P_IP) {
279 printf("ip protocol: (%d bytes)\n",i_o);
280 ip_hdr=(struct iphdr *)(package+p_o+w_o+e_o);
281 printf("version = %x ",ntohs(ip_hdr->version));
282 printf("header_length = %x \n",ntohs(ip_hdr->ihl));
283 printf("service = %x ",ntohs(ip_hdr->tos));
284 printf("total_length(dec.) = %d \n",ntohs(ip_hdr->tot_len));
285 printf("source_ip: ");
288 (ip_hdr->saddr&(0xff<<(8*i)))>>(8*i),
291 printf("destination_ip: ");
294 (ip_hdr->daddr&(0xff<<(8*i)))>>(8*i),
297 printf("ip_id = %x ",ntohs(ip_hdr->id));
298 printf("ip_offset = %x \n",ntohs(ip_hdr->frag_off));
299 printf("time2live = %x ip_proto = %x\n",ntohs(ip_hdr->ttl),
300 ntohs(ip_hdr->protocol));
301 // printf("chksum: %x\n",ntohs(ip_hdr->ip_sum));
305 /* check what we have ... */
306 printf("all dump: (hex)\n");
307 for(i=p_o+w_o;i<pcap_header->caplen;i++)
308 printf("%x ",*(package+i));
310 printf("all dump: (char)\n");
311 for(i=p_o+w_o;i<pcap_header->caplen;i++)
312 printf("%c ",*(package+i));
316 int hop_channel(struct info_struct *info,int foo_fd) {
317 if((info->mmode-0x30==1) && (strncmp(info->dev,"wlan",4)==0)) {
319 struct iwreq my_iwreq;
321 if (info->channel>=14) info->channel=1;
323 memset(&my_iwreq,0,sizeof(my_iwreq));
324 strcpy(my_iwreq.ifr_name,info->dev);
325 printf("debug: channel = %d\n",info->channel);
327 my_iwreq.u.freq.m=info->channel;
328 if((ioctl(foo_fd,SIOCSIWFREQ,&my_iwreq))==-1) {
329 printf("unable to hop channels\n");