Diffstat (limited to 'noncore/net/wellenreiter/daemon/source/sniffer.c') (more/less context) (ignore whitespace changes)
| -rw-r--r-- | noncore/net/wellenreiter/daemon/source/sniffer.c | 437 |
1 files changed, 437 insertions, 0 deletions
diff --git a/noncore/net/wellenreiter/daemon/source/sniffer.c b/noncore/net/wellenreiter/daemon/source/sniffer.c new file mode 100644 index 0000000..6f40503 --- a/dev/null +++ b/noncore/net/wellenreiter/daemon/source/sniffer.c @@ -0,0 +1,437 @@ +/* Its just a simple rfmon mode sniffer + i hope my C is at last a bit better then in my + early days :-). + This works only with cisco wireless cards with an rfmon + able driver and not with wifi stuff. + Btw. did i mention that i hate C? + + To compile use: + gcc wlan-sniffer.c -o wlan-sniffer -lpcap + + use it like this: + wlan-sniffer interface + +*/ +#include "sniffer.h" + +int main(int argc, char **argv) +{ + int ret; /* return code */ + ret = card_into_monitormode (SNIFFER_DEVICE, CARD_TYPE_NG); + if (ret == -1) + { + exit(-1); + } + start_sniffing (SNIFFER_DEVICE); + + return 0; +} + +int card_into_monitormode (char * device, int cardtype) +{ + int ret = -1; + int datalink; /* used for getting the pcap datalink type */ + char CiscoRFMON[35] = "/proc/driver/aironet/"; + FILE *CISCO_CONFIG_FILE; + char errbuf[PCAP_ERRBUF_SIZE]; + pcap_t *handle; + + /* Checks if we have a device to sniff on */ + if(device == NULL) + { + printf ("Fatal error i did not have any interfaces to sniff on\n"); + exit(1); + } + + /* Setting the prmiscous and up flag to the interface */ + if (card_set_promisc_up (device) == 0) + { + printf ("Interface flags correctly set using ifconfig\n"); + } + + /* Check the cardtype and executes the commands to go into monitor mode */ + if (cardtype == CARD_TYPE_CISCO) /* I got a cisco card */ + { + /* bring the sniffer into rfmon mode */ + snprintf(CiscoRFMON, sizeof(CiscoRFMON),DEFAULT_PATH, device); + CISCO_CONFIG_FILE = fopen(CiscoRFMON,"w"); + fputs ("Mode: r",CISCO_CONFIG_FILE); + fputs ("Mode: y",CISCO_CONFIG_FILE); + fputs ("XmitPower: 1",CISCO_CONFIG_FILE); + fclose(CISCO_CONFIG_FILE); + } + else if (cardtype == CARD_TYPE_NG) + { + char wlanngcmd[62]; + snprintf(wlanngcmd, sizeof(wlanngcmd),"%s %s lnxreq_wlansniff channel=1 enable=true",WLANCTL_PATH,device); + if (ret = (system (wlanngcmd)) != 0) + { + printf ("\n Fatal error could not set %s in raw mode, check cardtype\n",device); + exit(1); + } + } + else if (cardtype == CARD_TYPE_HOSTAP) + { + printf ("Got a host-ap card, nothing is implemented now\n"); + } + + + /* Check the interface if it is in the correct raw mode */ + handle = pcap_open_live(device, BUFSIZ, 1, 0, errbuf); + + /* getting the datalink type */ + datalink = pcap_datalink(handle); + + if (datalink == DLT_IEEE802_11) /* Rawmode is IEEE802_11 */ + { + printf ("Your successfully listen on %s in 802.11 raw mode\n",device); + pcap_close(handle); + return (0); + + } + else + { + printf ("Fatal error, cannot continue, your interface %s does not work in the correct 802.11 raw mode, check you driver please\n",device); + pcap_close(handle); + exit(1); + } +} + +int card_set_promisc_up (char * device) +{ + int ret; + char ifconfigcmd[32]; + snprintf(ifconfigcmd,sizeof(ifconfigcmd),SBIN_PATH, device); + ret = system (ifconfigcmd); + if (ret > 0) + { + printf ("\nFatal error, could not execute %s please check your card,binary location and permission\n",ifconfigcmd); + exit(1); + } + return(0); +} + +int start_sniffing (char * device) +{ + int ret; /* return code */ + pcap_t *handletopcap; + char errbuf[PCAP_ERRBUF_SIZE]; + struct pcap_pkthdr header; /* The header that pcap gives us */ + const u_char *packet; /* The actual packet */ + + /* opening the pcap for sniffing */ + handletopcap = pcap_open_live(device, BUFSIZ, 1, 1000, errbuf); + + /* Next few lines a taken out of kismet */ + #ifdef HAVE_PCAP_NONBLOCK + pcap_setnonblock(handletopcap, 1, errstr); + #endif + + /*start scanning */ + pcap_loop(handletopcap,-1,process_packets,NULL); + + printf("\nDone processing packets... wheew!\n"); + return 0; +} + +void process_packets(u_char *useless,const struct pcap_pkthdr* pkthdr,const u_char* packet) +{ + u_int caplen = pkthdr->caplen; + u_int length = pkthdr->len; + u_int16_t fc; + u_int HEADER_LENGTH; + u_short extracted_ethertype; + int snapend; + int ret; + /* pinfo holds all interresting information for us */ + struct packetinfo pinfo; + struct packetinfo *pinfoptr; + pinfoptr=&pinfo; + + pinfoptr->isvalid = 0; + pinfoptr->pktlen = pkthdr->len; + if (caplen < IEEE802_11_FC_LEN) + { + /* This is a garbage packet, because is does not long enough + to hold a 802.11b header */ + pinfoptr->isvalid = 0; + return; + } + + /* Gets the framecontrol bits (2bytes long) */ + fc = EXTRACT_LE_16BITS(packet); + + HEADER_LENGTH = GetHeaderLength(fc); + + if (caplen < HEADER_LENGTH) + { + /* This is a garbage packet, because it is not long enough + to hold a correct header of its type */ + pinfoptr->isvalid = 0; + return; + } + + /* Decode 802.11b header out of the packet */ + if (decode_80211b_hdr(packet,pinfoptr) == 0) + { + /* Justification of the ofset to further process the packet */ + length -= HEADER_LENGTH; + caplen -= HEADER_LENGTH; + packet += HEADER_LENGTH; + } + else + { /* Something is wrong,could not be a correct packet */ + return; + } + + switch (FC_TYPE(fc)) + { + /* Is it a managemnet frame? */ + case T_MGMT: + switch (FC_SUBTYPE(fc)) + { /* Is it a beacon frame? */ + case ST_BEACON: + if (handle_beacon(fc, packet,pinfoptr) ==0) + { + if (!strcmp(pinfoptr->desthwaddr,"ff:ff:ff:ff:ff:ff") == 0) + { + /* Every beacon must have the broadcast as destination + so it must be a shitti packet */ + pinfoptr->isvalid = 0; + return; + } + if (pinfoptr->cap_ESS == pinfoptr->cap_IBSS) + { + /* Only one of both are possible, so must be + a noise packet, if this comes up */ + pinfoptr->isvalid = 0; + return; + } + if (pinfoptr->channel < 1 || pinfoptr->channel > 14) + { + /* Only channels between 1 and 14 are possible + others must be noise packets */ + pinfoptr->isvalid = 0; + return; + } + + /* Decoding successfull of beacon frame */ + if (pinfoptr->cap_ESS == 1 &&pinfoptr->cap_IBSS ==0) + { + printf ("\nHave found an accesspoint:"); + } + else if(pinfoptr->cap_ESS == 0 && pinfoptr->cap_IBSS == 1) + { + printf ("\nHave found an AD-HOC station:"); + + } + if (strcmp (pinfoptr->ssid,NONBROADCASTING) ==0) + { + printf ("\n\tOn a non-broadcasting network"); + } + else + { + printf ("\n\tOn network : %s",pinfoptr->ssid); + } + printf ("\n\tLen SSID : %d",pinfoptr->ssid_len); + printf ("\n\tOn Channel : %d",pinfoptr->channel); + printf ("\n\tEncryption : %s", pinfoptr->cap_WEP ? "ON" : "OFF"); + printf ("\n\tMacaddress : %s",pinfoptr->sndhwaddr); + printf ("\n\tBssid : %s",pinfoptr->bssid); + printf ("\n\tDest : %s\n",pinfoptr->desthwaddr); + } + break; + default: + printf("Unknown IEEE802.11 frame subtype (%d)",FC_SUBTYPE(fc)); + break; + } /* End of switch over different mgt frame types */ + + break; + case T_CTRL: + // decode_control_frames(fc, packet); + printf ("Its a control frame"); + break; + case T_DATA: + // decode_data_frames(fc, packet); + printf ("Its a date frame"); + break; + default: + printf("Unknown IEEE802.11 frame type (%d)",FC_TYPE(fc)); + break; + } +} + + +/* This decodes the 802.11b frame header out of the 802.11b packet + all the infos is placed into the packetinfo structure */ +int decode_80211b_hdr(const u_char *p,struct packetinfo *ppinfo) +{ + char * ret; + char testme[16]; + const struct mgmt_header_t *mgthdr = (const struct mgmt_header_t *) p; + ppinfo->fcsubtype = FC_SUBTYPE(mgthdr->fc); + + /* Get the sender, bssid and dest mac address */ + etheraddr_string(mgthdr->bssid,ppinfo->bssid); + etheraddr_string(mgthdr->da,ppinfo->desthwaddr); + etheraddr_string(mgthdr->sa,ppinfo->sndhwaddr); + ppinfo->fc_wep = FC_WEP(mgthdr->fc); + return(0); +} + + +void etheraddr_string(register const u_char *ep,char * text) +{ + static char hex[] = "0123456789abcdef"; + register u_int i, j; + register char *cp; + char buf[sizeof("00:00:00:00:00:00")]; + cp = buf; + if ((j = *ep >> 4) != 0) + *cp++ = hex[j]; + *cp++ = hex[*ep++ & 0xf]; + for (i = 5; (int)--i >= 0;) { + *cp++ = ':'; + if ((j = *ep >> 4) != 0) + *cp++ = hex[j]; + *cp++ = hex[*ep++ & 0xf]; + } + *cp = '\0'; + strcpy(text,buf); + return; +} + +int handle_beacon(u_int16_t fc, const u_char *p,struct packetinfo *ppinfo) +{ + struct mgmt_body_t pbody; + int offset = 0; + + /* Get the static informations out of the packet */ + memset(&pbody, 0, sizeof(pbody)); + memcpy(&pbody.timestamp, p, 8); + offset += 8; + pbody.beacon_interval = EXTRACT_LE_16BITS(p+offset); + offset += 2; + pbody.capability_info = EXTRACT_LE_16BITS(p+offset); + offset += 2; + + /* Gets the different flags out of the capabilities */ + ppinfo->cap_ESS = CAPABILITY_ESS(pbody.capability_info); + ppinfo->cap_IBSS = CAPABILITY_IBSS(pbody.capability_info); + ppinfo->cap_WEP = CAPABILITY_PRIVACY(pbody.capability_info); + + /* Gets the tagged elements out of the packets */ + while (offset + 1 < ppinfo->pktlen) + { + switch (*(p + offset)) + { + case E_SSID: + memcpy(&(pbody.ssid),p+offset,2); offset += 2; + if (pbody.ssid.length > 0) + { + memcpy(&(pbody.ssid.ssid),p+offset,pbody.ssid.length); offset += pbody.ssid.length; + pbody.ssid.ssid[pbody.ssid.length]='\0'; + if (strcmp(pbody.ssid.ssid,"")==0) + { + ppinfo->ssid = NONBROADCASTING; + } + else + { + ppinfo->ssid = pbody.ssid.ssid; + } + ppinfo->ssid_len = pbody.ssid.length; + } + break; + case E_CHALLENGE: + memcpy(&(pbody.challenge),p+offset,2); offset += 2; + if (pbody.challenge.length > 0) + { + memcpy(&(pbody.challenge.text),p+offset,pbody.challenge.length); offset += pbody.challenge.length; + pbody.challenge.text[pbody.challenge.length]='\0'; + } + break; + case E_RATES: + memcpy(&(pbody.rates),p+offset,2); offset += 2; + if (pbody.rates.length > 0) { + memcpy(&(pbody.rates.rate),p+offset,pbody.rates.length); offset += pbody.rates.length; + } + break; + case E_DS: + memcpy(&(pbody.ds),p+offset,3); offset +=3; + ppinfo->channel = pbody.ds.channel; + break; + case E_CF: + memcpy(&(pbody.cf),p+offset,8); offset +=8; + break; + case E_TIM: + memcpy(&(pbody.tim),p+offset,2); offset +=2; + memcpy(&(pbody.tim.count),p+offset,3); offset +=3; + if ((pbody.tim.length -3) > 0) + { + memcpy((pbody.tim.bitmap),p+(pbody.tim.length -3),(pbody.tim.length -3)); + offset += pbody.tim.length -3; + } + break; + default: +#if 0 + printf("(1) unhandled element_id (%d) ", *(p+offset) ); +#endif + offset+= *(p+offset+1) + 2; + break; + } /* end of switch*/ + } /* end of for loop */ + return(0); + + + + +} /* End of handle_beacon */ + + +static int GetHeaderLength(u_int16_t fc) +{ + int iLength=0; + + switch (FC_TYPE(fc)) { + case T_MGMT: + iLength = MGMT_HEADER_LEN; + break; + case T_CTRL: + switch (FC_SUBTYPE(fc)) { + case CTRL_PS_POLL: + iLength = CTRL_PS_POLL_LEN; + break; + case CTRL_RTS: + iLength = CTRL_RTS_LEN; + break; + case CTRL_CTS: + iLength = CTRL_CTS_LEN; + break; + case CTRL_ACK: + iLength = CTRL_ACK_LEN; + break; + case CTRL_CF_END: + iLength = CTRL_END_LEN; + break; + case CTRL_END_ACK: + iLength = CTRL_END_ACK_LEN; + break; + default: + iLength = 0; + break; + } + break; + case T_DATA: + if (FC_TO_DS(fc) && FC_FROM_DS(fc)) + iLength = 30; + else + iLength = 24; + break; + default: + printf("unknown IEEE802.11 frame type (%d)", + FC_TYPE(fc)); + break; + } + + return iLength; +} |