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capture.c
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capture.c
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/*
* Copyright (c) 2005-2010 Thierry FOURNIER
* $Id: capture.c 690 2008-03-31 18:36:43Z $
*
*/
#include "config.h"
#include <pcap.h>
#include <stdlib.h>
#include <fcntl.h>
#include <string.h>
#include <pwd.h>
#include <unistd.h>
#include <grp.h>
#include <stdio.h>
#include <errno.h>
#include <sys/select.h>
#include <sys/param.h>
#if (__Linux__ || __FreeBSD__ || __NetBSD__ || __OpenBSD__)
# include <sys/sysctl.h>
#endif
#if (__sun)
# include <sys/sockio.h>
#endif
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#if (__NetBSD__ || __FreeBSD__ || __OpenBSD__ || __sun )
# include <net/if_dl.h>
#endif
#include <arpa/inet.h>
#include "arpalert.h"
#include "capture.h"
#include "sens.h"
#include "log.h"
#include "loadconfig.h"
#include "data.h"
#include "alerte.h"
#include "sens_timeouts.h"
#include "loadmodule.h"
#include "logalert.h"
#include "macname.h"
#include "func_time.h"
#include "func_str.h"
#include "alertes.h"
#define SNAP_LEN 1514
extern int errno;
// constantes
struct ether_addr null_mac = { { 0, 0, 0, 0, 0, 0 } };
struct in_addr null_ip = { .s_addr = 0 };
struct in_addr broadcast = { .s_addr = 0xffffffff };
struct timeval next_abus_reset;
struct capt *first_capt;
// persistent var
unsigned int seq = 0;
int abus = 50;
int base = 21;
int count = 0;
struct timeval last_count;
// lib pcap error buffer
char pcap_err[PCAP_ERRBUF_SIZE];
void callback(u_char *, const struct pcap_pkthdr *, const u_char *);
// alert bitfiels
U_INT32_T alert_bitfield;
U_INT32_T mod_bitfield;
U_INT32_T log_bitfield;
// convert alert flag to alert number
int flag_to_no(U_INT32_T flag){
switch(flag){
case FLAG_IPCHG: return AL_IP_CHANGE; break;
case FLAG_ALLOW: return AL_UNKNOWN_ADDRESS; break;
case FLAG_DENY: return AL_BLACK_LISTED; break;
case FLAG_NEW: return AL_NEW; break;
case FLAG_UNAUTH_RQ: return AL_UNAUTHRQ; break;
case FLAG_ABUS: return AL_RQABUS; break;
case FLAG_BOGON: return AL_MAC_ERROR; break;
case FLAG_FLOOD: return AL_FLOOD; break;
case FLAG_NEWMAC: return AL_NEW_MAC; break;
case FLAG_MACCHG: return AL_MAC_CHANGE; break;
case FLAG_MACEXPIRE: return AL_MAC_EXPIRE; break;
}
return -1;
}
pcap_t *cap_init_device(struct capt *cap_id){
char *filtre;
struct bpf_program bp;
int promisc;
pcap_t *idcap;
#if (__sun)
int sock_fd;
struct arpreq ar;
struct sockaddr_in *soap,*soap2;
struct lifreq ifr;
#endif
#if (__linux__)
int sock_fd;
struct ifreq ifr;
#endif
#if (__NetBSD__ || __FreeBSD__ || __OpenBSD__)
int mib[6];
size_t len;
char *buf;
unsigned char *ptr;
struct if_msghdr *ifm;
struct sockaddr_dl *sdl;
#endif
// find my arp adresses for this device
#if (__sun)
if((sock_fd = socket(AF_INET, SOCK_DGRAM, 0)) == -1 ){
logmsg(LOG_ERR, "[%s %i] socket[%d]: %s",
__FILE__, __LINE__, errno, strerror(errno));
exit(1);
}
// get ip addr
memset(&ifr, 0, sizeof(ifr));
strncpy(ifr.lifr_name, cap_id->device, LIFNAMSIZ);
if(ioctl(sock_fd, SIOCGLIFADDR, &ifr) == -1 ){
logmsg(LOG_ERR, "[%s %i] ioctl[%d] : %s",
__FILE__, __LINE__, errno, strerror(errno));
exit(1);
}
soap=(struct sockaddr_in *)&(ifr.lifr_addr);
soap2=(struct sockaddr_in *)&(ar.arp_pa);
*soap2 = *soap;
// get mac addr
if(ioctl(sock_fd, SIOCGARP, &ar) < 0){
logmsg(LOG_ERR, "[%s %i] ioctl[%d] : %s",
__FILE__, __LINE__, errno, strerror(errno));
exit(1);
}
DATA_CPY(&(cap_id->mac), &(ar.arp_ha.sa_data));
close(sock_fd);
#endif // (__sun)
#if (__linux__)
if((sock_fd = socket(AF_INET, SOCK_DGRAM, 0)) == -1 ){
logmsg(LOG_ERR, "[%s %i] socket[%d]: %s",
__FILE__, __LINE__, errno, strerror(errno));
exit(1);
}
memset(&ifr, 0, sizeof(ifr));
strncpy(ifr.ifr_name, cap_id->device, sizeof(ifr.ifr_name));
if(ioctl(sock_fd, SIOCGIFHWADDR, &ifr) == -1 ){
logmsg(LOG_ERR, "[%s %i] ioctl[%d] : %s",
__FILE__, __LINE__, errno, strerror(errno));
exit(1);
}
DATA_CPY(&(cap_id->mac), &ifr.ifr_addr.sa_data);
close(sock_fd);
#endif // (__linux__)
#if (__NetBSD__ || __FreeBSD__ || __OpenBSD__)
mib[0] = CTL_NET;
mib[1] = AF_ROUTE;
mib[2] = 0;
mib[3] = AF_LINK;
mib[4] = NET_RT_IFLIST;
if ((mib[5] = if_nametoindex(cap_id->device)) == 0) {
logmsg(LOG_ERR, "[%s %i] if_nametoindex[%d]: %s",
__FILE__, __LINE__, errno, strerror(errno));
exit(1);
}
if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0) {
logmsg(LOG_ERR, "[%s %i] sysctl[%d]: %s",
__FILE__, __LINE__, errno, strerror(errno));
exit(1);
}
if ((buf = malloc(len)) == NULL) {
logmsg(LOG_ERR, "[%s %i] malloc[%d]: %s",
__FILE__, __LINE__, errno, strerror(errno));
exit(1);
}
if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
logmsg(LOG_ERR, "[%s %i] sysctl[%d]: %s",
__FILE__, __LINE__, errno, strerror(errno));
exit(1);
}
ifm = (struct if_msghdr *)buf;
sdl = (struct sockaddr_dl *)(ifm + 1);
ptr = (unsigned char *)LLADDR(sdl);
DATA_CPY(&(cap_id->mac), ptr);
free(buf);
#endif // (__NetBSD__ || __FreeBSD__ || __OpenBSD__)
// promiscuous mode ?
if(config[CF_PROMISC].valeur.integer==TRUE){
promisc = 1;
} else {
promisc = 0;
}
// interface initialization
idcap = pcap_open_live(cap_id->device, SNAP_LEN, promisc, 10, pcap_err);
if(idcap == NULL){
logmsg(LOG_ERR, "[%s %i] pcap_open_live error: %s",
__FILE__, __LINE__, pcap_err);
exit(1);
}
// check type of link
if(pcap_datalink(idcap) != DLT_EN10MB){
logmsg(LOG_ERR, "[%s %i] pcap_datalink errror: "
"unrecognized link",
__FILE__, __LINE__);
exit(1);
}
// generate filter
if(config[CF_ONLY_ARP].valeur.integer == TRUE){
filtre = "arp or rarp";
} else {
filtre = "";
}
// filter initiliazation
if(pcap_compile(idcap, &bp, filtre, 0x100, 0) < 0){
logmsg(LOG_ERR, "[%s %i] pcap_compile error: %s",
__FILE__, __LINE__, pcap_geterr(idcap));
exit(1);
}
// filter application
if(pcap_setfilter(idcap, &bp)<0){
logmsg(LOG_ERR, "[%s %i] pcap_setfilter error: %s",
__FILE__, __LINE__, pcap_geterr(idcap));
exit(1);
}
#ifdef DEBUG
logmsg(LOG_DEBUG, "[%s %d %s] pcap_setfilter [%s]: ok",
__FILE__, __LINE__, __FUNCTION__, filtre);
#endif
return idcap;
}
void cap_init(void){
struct capt *netif;
char *device = NULL;
char *base, *parse;
int state, gbreak;
first_capt = NULL;
alert_bitfield = 0;
mod_bitfield = 0;
log_bitfield = 0;
// init alert system
#define IS_CONF(x) config[(x)].valeur.integer == TRUE
if(IS_CONF(CF_LOG_FLOOD)) log_bitfield |= FLAG_FLOOD;
if(IS_CONF(CF_ALERT_FLOOD)) alert_bitfield |= FLAG_FLOOD;
if(IS_CONF(CF_MOD_FLOOD)) mod_bitfield |= FLAG_FLOOD;
if(IS_CONF(CF_LOG_NEWMAC)) log_bitfield |= FLAG_NEWMAC;
if(IS_CONF(CF_ALERT_NEWMAC)) alert_bitfield |= FLAG_NEWMAC;
if(IS_CONF(CF_MOD_NEWMAC)) mod_bitfield |= FLAG_NEWMAC;
if(IS_CONF(CF_LOG_NEW)) log_bitfield |= FLAG_NEW;
if(IS_CONF(CF_ALERT_NEW)) alert_bitfield |= FLAG_NEW;
if(IS_CONF(CF_MOD_NEW)) mod_bitfield |= FLAG_NEW;
if(IS_CONF(CF_LOG_MACCHG)) log_bitfield |= FLAG_MACCHG;
if(IS_CONF(CF_ALERT_MACCHG)) alert_bitfield |= FLAG_MACCHG;
if(IS_CONF(CF_MOD_MACCHG)) mod_bitfield |= FLAG_MACCHG;
if(IS_CONF(CF_LOG_IPCHG)) log_bitfield |= FLAG_IPCHG;
if(IS_CONF(CF_ALERT_IPCHG)) alert_bitfield |= FLAG_IPCHG;
if(IS_CONF(CF_MOD_IPCHG)) mod_bitfield |= FLAG_IPCHG;
if(IS_CONF(CF_LOG_UNAUTH_RQ)) log_bitfield |= FLAG_UNAUTH_RQ;
if(IS_CONF(CF_ALERT_UNAUTH_RQ)) alert_bitfield |= FLAG_UNAUTH_RQ;
if(IS_CONF(CF_MOD_UNAUTH_RQ)) mod_bitfield |= FLAG_UNAUTH_RQ;
if(IS_CONF(CF_LOG_BOGON)) log_bitfield |= FLAG_BOGON;
if(IS_CONF(CF_ALERT_BOGON)) alert_bitfield |= FLAG_BOGON;
if(IS_CONF(CF_MOD_BOGON)) mod_bitfield |= FLAG_BOGON;
if(IS_CONF(CF_LOG_ABUS)) log_bitfield |= FLAG_ABUS;
if(IS_CONF(CF_ALERT_ABUS)) alert_bitfield |= FLAG_ABUS;
if(IS_CONF(CF_MOD_ABUS)) mod_bitfield |= FLAG_ABUS;
if(IS_CONF(CF_LOG_ALLOW)) log_bitfield |= FLAG_ALLOW;
if(IS_CONF(CF_ALERT_ALLOW)) alert_bitfield |= FLAG_ALLOW;
if(IS_CONF(CF_MOD_ALLOW)) mod_bitfield |= FLAG_ALLOW;
if(IS_CONF(CF_LOG_DENY)) log_bitfield |= FLAG_DENY;
if(IS_CONF(CF_ALERT_DENY)) alert_bitfield |= FLAG_DENY;
if(IS_CONF(CF_MOD_DENY)) mod_bitfield |= FLAG_DENY;
if(IS_CONF(CF_LOG_EXPIRE)) log_bitfield |= FLAG_MACEXPIRE;
if(IS_CONF(CF_ALERT_EXPIRE)) alert_bitfield |= FLAG_MACEXPIRE;
if(IS_CONF(CF_MOD_EXPIRE)) mod_bitfield |= FLAG_MACEXPIRE;
// if no device specified, auto select the first
if(config[CF_IF].valeur.string == NULL ||
config[CF_IF].valeur.string[0] == 0){
if((device = pcap_lookupdev(pcap_err))==NULL){
logmsg(LOG_ERR, "[%s %i] pcap_lookupdev: %s",
__FILE__, __LINE__, pcap_err);
exit(1);
}
logmsg(LOG_NOTICE, "Auto selected device: %s", device);
netif = malloc(sizeof(struct capt));
if(netif == NULL){
logmsg(LOG_ERR, "[%s %i] malloc[%d]: %s",
__FILE__, __LINE__, errno, strerror(errno));
exit(1);
}
netif->next = NULL;
netif->device = strdup(device);
netif->pcap = cap_init_device(netif);
first_capt = netif;
}
// parsing conf
else {
base = strdup(config[CF_IF].valeur.string);
parse = base;
state = 0;
gbreak = 0;
while(TRUE){
if(state == 0 && *parse != ','){
device = parse;
state = 1;
}
else if(state == 1 && ( *parse == ',' || *parse == 0)){
if(*parse == 0) gbreak = 1;
*parse = 0;
state = 0;
// generate node for interfaces chain and init interface
netif = malloc(sizeof(struct capt));
if(netif == NULL){
logmsg(LOG_ERR, "[%s %i] malloc[%d]: %s",
__FILE__, __LINE__, errno, strerror(errno));
exit(1);
}
netif->device = strdup(device);
netif->pcap = cap_init_device(netif);
logmsg(LOG_NOTICE, "Selected device: %s", device);
// chain
netif->next = first_capt;
first_capt = netif;
if(gbreak == 1) break;
}
else if(*parse == 0){
logmsg(LOG_ERR, "Error when parsing device: \"%s\"",
config[CF_IF].valeur.string);
exit(1);
}
parse ++;
}
free(base);
}
gettimeofday(&next_abus_reset, NULL);
last_count.tv_sec = next_abus_reset.tv_sec;
last_count.tv_usec = next_abus_reset.tv_usec;
next_abus_reset.tv_sec += 1;
}
// get device name and return pointeur to her struct capt
struct capt *cap_get_interface(char *device){
struct capt *netif;
netif = first_capt;
while(netif != NULL){
if(strcmp(device, netif->device)==0){
return netif;
}
netif = netif->next;
}
return NULL;
}
// gen bitfield for select
int cap_gen_bitfield(fd_set *bf){
struct capt *netif;
int fd, max = 0;
netif = first_capt;
while(netif != NULL){
fd = pcap_fileno(netif->pcap);
FD_SET(fd, bf);
if(fd > max) max = fd;
netif = netif->next;
}
return(max);
}
// proceed return of select
void cap_sniff(fd_set *bf){
struct capt *netif;
netif = first_capt;
while(netif != NULL){
if(FD_ISSET(pcap_fileno(netif->pcap), bf)){
if(pcap_dispatch(netif->pcap, 1, callback, (void*)netif) < 0){
logmsg(LOG_ERR, "[%s %i] pcap_dispatch error: %s",
__FILE__, __LINE__,
pcap_geterr(netif->pcap));
}
}
netif = netif->next;
}
}
// return TRUE if the alert interval is ok
int interval_ok(struct timeval *tv){
struct timeval res;
time_sous(¤t_t, tv, &res);
if(res.tv_sec >= config[CF_ANTIFLOOD_INTER].valeur.integer){
return TRUE;
}
return FALSE;
}
// centralized alerts system
void send_alert(struct ether_addr *mac_sender,
struct in_addr ip_sender,
U_INT32_T flag,
struct ether_addr *ref_mac,
struct in_addr ref_ip,
char *interface){
int alert_no;
char str_ref[MAC_SIZE];
char str_eth_mac_sender[MAC_SIZE];
char str_arp_ip_sender[16];
char *vendor = NULL;
// convert alert flag into alert number
alert_no = flag_to_no(flag);
if((alert_bitfield & flag) != 0x00000000 ||
(log_bitfield & flag) != 0x00000000){
// convert eth mac sender to string
MAC_TO_STR(*mac_sender, &str_eth_mac_sender[0]);
// convert arp ip sender into string
strcpy(str_arp_ip_sender, inet_ntoa(ip_sender));
// convert references
switch(alert_no){
case AL_IP_CHANGE:
case AL_UNAUTHRQ:
strcpy(str_ref, inet_ntoa(ref_ip));
break;
case AL_MAC_ERROR:
case AL_FLOOD:
MAC_TO_STR(*ref_mac, str_ref);
break;
default:
str_ref[0] = 0;
break;
}
}
// get vendor
if(config[CF_LOG_VENDOR].valeur.integer |
config[CF_ALERT_VENDOR].valeur.integer |
config[CF_MOD_VENDOR].valeur.integer){
vendor = get_vendor(mac_sender);
}
else {
vendor = NULL;
}
// send alert script
if((alert_bitfield & flag) != 0x00000000){
alerte_script(str_eth_mac_sender, str_arp_ip_sender, alert_no,
str_ref, interface, vendor);
}
// send alert module
if((mod_bitfield & flag) != 0x00000000){
alerte_mod(mac_sender, ip_sender, alert_no,
ref_mac, ref_ip, interface, vendor);
}
// send alert log
if((log_bitfield & flag) != 0x00000000){
alerte_log(seq,
str_eth_mac_sender, str_arp_ip_sender,
alert_no, str_ref, interface, vendor);
}
}
// processing arp errors
void callback(u_char *user, const struct pcap_pkthdr *h,
const u_char *buff){
int flag_is_arp = FALSE;
struct ether_addr __eth_mac_sender;
struct ether_addr __eth_mac_rcpt;
struct ether_addr *eth_mac_sender = (struct ether_addr *)&null_mac;
struct ether_addr *eth_mac_rcpt = (struct ether_addr *)&null_mac;
struct ether_addr __arp_mac_sender;
struct ether_addr __arp_mac_rcpt;
struct ether_addr *arp_mac_sender = (struct ether_addr *)&null_mac;
struct ether_addr *arp_mac_rcpt = (struct ether_addr *)&null_mac;
struct in_addr arp_ip_sender = { .s_addr = 0x00000000 };
struct in_addr arp_ip_rcpt = { .s_addr = 0x00000000 };
struct data_pack *eth_data = NULL;
struct data_pack *ip_data = NULL;
int flag_unknown_address = TRUE;
struct capt *cap_id= (struct capt *)user;
struct timeval sous;
// string conversions
char str_eth_mac_sender[MAC_SIZE];
char str_eth_mac_rcpt[MAC_SIZE];
char str_arp_mac_sender[MAC_SIZE];
char str_arp_mac_rcpt[MAC_SIZE];
char str_arp_ip_sender[16];
char str_arp_ip_rcpt[16];
// inter
struct ether_header * eth_header;
struct arphdr * arp_header;
struct timeval res;
// if more than N arp request in one second,
// dont execute capture functions
time_sous(¤t_t, &last_count, &res);
if(count > config[CF_ANTIFLOOD_GLOBAL].valeur.integer &&
res.tv_sec < config[CF_ANTIFLOOD_INTER].valeur.integer) {
return;
}
#ifdef DEBUG
logmsg(LOG_DEBUG, "[%s %d %s] capture packet",
__FILE__, __LINE__, __FUNCTION__);
#endif
//increment sequence
seq++;
// set structurs
eth_header = (struct ether_header *)buff;
// get a ethernet mac source
memcpy(&__eth_mac_sender, &(eth_header->ether_shost), 6);
eth_mac_sender = &__eth_mac_sender;
// get a ethernet mac dest
memcpy(&__eth_mac_rcpt, &(eth_header->ether_dhost), 6);
eth_mac_rcpt = &__eth_mac_rcpt;
// get properties memorised of this mac
eth_data = data_exist(eth_mac_sender, cap_id);
if(eth_data != NULL) {
flag_unknown_address = FALSE;
}
// is an arp request
if(ntohs(eth_header->ether_type) == ETHERTYPE_ARP){
char *arp_data_base;
// type la partie mac address
arp_header = (struct arphdr *)(buff +
sizeof(struct ether_header));
// is an arp who-has or is-at ?
if(ntohs(arp_header->ar_op) == ARPOP_REQUEST ||
ntohs(arp_header->ar_op) == ARPOP_REPLY ){
// set flag "is arp"
flag_is_arp = TRUE;
// count number of request in 1 second
time_sous(¤t_t, &last_count, &res);
if(res.tv_sec < 1){
count ++;
} else {
count = 1;
last_count.tv_sec++;
}
}
// compute the base (sender MAC address)
arp_data_base = (char *)(buff +
sizeof(struct ether_header) +
sizeof(struct arphdr));
// get arp mac sender
memcpy(&__arp_mac_sender, arp_data_base, arp_header->ar_hln);
arp_mac_sender = &__arp_mac_sender;
// base = sender IP address
arp_data_base += arp_header->ar_hln;
// get ip of arp sender
memcpy(&arp_ip_sender.s_addr, arp_data_base, arp_header->ar_pln);
// base = target mac address
arp_data_base += arp_header->ar_pln;
// get arp mac rcpt
memcpy(&__arp_mac_rcpt, arp_data_base, arp_header->ar_hln);
arp_mac_rcpt = &__arp_mac_rcpt;
// base = target IP address
arp_data_base += arp_header->ar_hln;
// get ip of arp rcpt
memcpy(&arp_ip_rcpt.s_addr, arp_data_base, arp_header->ar_pln);
if(config[CF_DUMP_PAQUET].valeur.integer == TRUE ||
config[CF_DUMP_PACKET].valeur.integer == TRUE){
// convert eth mac sender to string
MAC_TO_STR(eth_mac_sender[0], str_eth_mac_sender);
// convert eth mac rcpt to string
MAC_TO_STR(eth_mac_rcpt[0], str_eth_mac_rcpt);
// convert arp mac sender to sting
MAC_TO_STR(arp_mac_sender[0], str_arp_mac_sender);
// convert arp mac sender to sting
MAC_TO_STR(arp_mac_rcpt[0], str_arp_mac_rcpt);
// convert arp ip sender into string
strcpy(str_arp_ip_sender, inet_ntoa(arp_ip_sender));
// convert arp ip rcpt into string
strcpy(str_arp_ip_rcpt, inet_ntoa(arp_ip_rcpt));
if(ntohs(arp_header->ar_op) == ARPOP_REQUEST) {
logmsg(LOG_DEBUG,
"%s > %s, "
"length %d: arp who-has %s tell %s",
str_eth_mac_sender,
str_eth_mac_rcpt,
h->len,
str_arp_ip_rcpt,
str_arp_ip_sender);
}
else if(ntohs(arp_header->ar_op) == ARPOP_REPLY) {
logmsg(LOG_DEBUG,
"%s > %s, "
"length %d: arp reply %s is-at %s",
str_eth_mac_sender,
str_eth_mac_rcpt,
h->len,
str_arp_ip_sender,
str_arp_mac_sender);
}
}
}
// =====================================
// ARP general flood detection
// =====================================
#ifdef DEBUG_DETECT
logmsg(LOG_DEBUG,
"[%s %d] -> \"ARP general flood detection\" Check ...",
__FILE__, __LINE__);
#endif
if(
// is an arp request
flag_is_arp == TRUE &&
// global arp flood
count > config[CF_ANTIFLOOD_GLOBAL].valeur.integer
){
#ifdef DEBUG_DETECT
logmsg(LOG_DEBUG, "[%s %d] -> DETECTED", __FILE__, __LINE__);
#endif
send_alert(eth_mac_sender, arp_ip_sender, FLAG_FLOOD,
&null_mac, null_ip, cap_id->device);
return;
}
// =====================================
// New mac adress detection
// =====================================
#ifdef DEBUG_DETECT
logmsg(LOG_DEBUG,
"[%s %d] -> \"New mac adress detection\" Check ...",
__FILE__, __LINE__);
#endif
if(
// mac adress inconue
eth_data == NULL &&
// ip unknown
arp_ip_sender.s_addr == 0
) {
#ifdef DEBUG_DETECT
logmsg(LOG_DEBUG, "[%s %d] -> DETECTED", __FILE__, __LINE__);
#endif
// add data to database
eth_data = data_add(eth_mac_sender, APPEND,
arp_ip_sender, cap_id);
// allow to dump data
data_rqdump();
send_alert(eth_mac_sender, arp_ip_sender, FLAG_NEWMAC,
&null_mac, null_ip, cap_id->device);
}
// =====================================
// New mac adress and ip detection
// =====================================
#ifdef DEBUG_DETECT
logmsg(LOG_DEBUG,
"[%s %d] -> \"New mac adress and ip detection\" Check ...",
__FILE__, __LINE__);
#endif
if (
// ip known
arp_ip_sender.s_addr != 0 &&
(
// mac adress inconue
eth_data == NULL ||
// ip inconue
eth_data->ip.s_addr == 0
)
) {
#ifdef DEBUG_DETECT
logmsg(LOG_DEBUG, "[%s %d] -> DETECTED", __FILE__, __LINE__);
#endif
// add data to database
if(eth_data == NULL) {
eth_data = data_add(eth_mac_sender, APPEND,
arp_ip_sender, cap_id);
} else {
eth_data->ip.s_addr = arp_ip_sender.s_addr;
index_ip(eth_data);
}
// allow to dump data
data_rqdump();
send_alert(eth_mac_sender, arp_ip_sender, FLAG_NEW,
&null_mac, null_ip, cap_id->device);
}
// =====================================
// test mac change
// =====================================
#ifdef DEBUG_DETECT
logmsg(LOG_DEBUG,
"[%s %d] -> \"test mac change\" Check ...",
__FILE__, __LINE__);
#endif
if(
// check if this alert is configured
(
config[CF_ALERT_MACCHG].valeur.integer == TRUE ||
config[CF_LOG_MACCHG].valeur.integer == TRUE ||
config[CF_MOD_MACCHG].valeur.integer == TRUE
) &&
// sender is known
arp_ip_sender.s_addr != 0 &&
// if the bitfield is not active
ISSET_MAC_CHANGE(eth_data->alerts) == FALSE &&
// sender exist
(ip_data = data_ip_exist(arp_ip_sender, cap_id)) != NULL &&
// have different mac address
//data_cmp(&ip_data->mac.octet[0], eth_mac_sender) != 0
//ip_data != eth_data
DATA_CMP(&ip_data->mac.ETHER_ADDR_OCTET[0],
ð_data->mac.ETHER_ADDR_OCTET[0]) != 0
){
#ifdef DEBUG_DETECT
logmsg(LOG_DEBUG, "[%s %d] -> DETECTED", __FILE__, __LINE__);
#endif
// maj ip in database
unindex_ip(arp_ip_sender, cap_id);
eth_data->ip.s_addr = arp_ip_sender.s_addr;
index_ip(eth_data);
// can dump database
data_rqdump();
send_alert(eth_mac_sender, arp_ip_sender, FLAG_MACCHG,
&ip_data->mac, null_ip, cap_id->device);
}
// =====================================
// test ip change
// =====================================
#ifdef DEBUG_DETECT
logmsg(LOG_DEBUG,
"[%s %d] -> \"test ip change\" Check ...",
__FILE__, __LINE__);
#endif
if(
// check if this alert is configured
(
config[CF_LOG_IPCHG].valeur.integer == TRUE ||
config[CF_ALERT_IPCHG].valeur.integer == TRUE ||
config[CF_MOD_IPCHG].valeur.integer == TRUE
) &&
// if ip known different than ip detected
eth_data->ip.s_addr != arp_ip_sender.s_addr &&
// if ip known differnent then a broadcast
// ( protect aliases )
eth_data->ip.s_addr != broadcast.s_addr &&
// if ip known different than a nul adress
// (mac already detected but whitout ip)
eth_data->ip.s_addr != 0 &&
// ip detected different than null adress
arp_ip_sender.s_addr != 0 &&
// if the bitfield is not active
ISSET_IP_CHANGE(eth_data->alerts) == FALSE &&
// check timeouts
interval_ok(&(eth_data->lastalert[0])) == TRUE
){
#ifdef DEBUG_DETECT
logmsg(LOG_DEBUG, "[%s %d] -> DETECTED", __FILE__, __LINE__);
#endif
// maj timeout
eth_data->lastalert[0].tv_sec = current_t.tv_sec;
eth_data->lastalert[0].tv_usec = current_t.tv_usec;
// can dump database
data_rqdump();
send_alert(eth_mac_sender, arp_ip_sender, FLAG_IPCHG,
&null_mac, eth_data->ip, cap_id->device);
// maj database
eth_data->ip.s_addr = arp_ip_sender.s_addr;
index_ip(eth_data);
}
// =====================================
// non authorized request
// =====================================
#ifdef DEBUG_DETECT
logmsg(LOG_DEBUG,
"[%s %d] -> \"non authorized request\" Check ...",
__FILE__, __LINE__);
#endif
if(
// check if this alert is configured
(
config[CF_LOG_UNAUTH_RQ].valeur.integer == TRUE ||
config[CF_ALERT_UNAUTH_RQ].valeur.integer == TRUE ||
config[CF_MOD_UNAUTH_RQ].valeur.integer == TRUE
) &&
// is an arp request
flag_is_arp == TRUE &&
// the authfile do not complited
config[CF_AUTHFILE].valeur.string != NULL &&
// if the bitfield is not active
ISSET_UNAUTH_RQ(eth_data->alerts) == FALSE &&
// if ignore me is active
(
config[CF_IGNORE_ME].valeur.integer == FALSE ||
(
DATA_CMP(&(cap_id->mac), eth_mac_rcpt) != 0 &&
DATA_CMP(&(cap_id->mac), eth_mac_sender) != 0
)
) &&
(
// permit to ignore acl for not referenced machines
config[CF_IGNORE_UNKNOWN].valeur.integer == FALSE ||
eth_data->flag == ALLOW
) &&
(
// permit to ignore arp self test
config[CF_IGNORESELFTEST].valeur.integer == FALSE ||
arp_ip_sender.s_addr != arp_ip_rcpt.s_addr
) &&
(
(
// normal flood control
config[CF_UNAUTH_TO_METHOD].valeur.integer == 1 &&
interval_ok(&(eth_data->lastalert[4])) == TRUE
) ||
(
// flood control by tuple (mac / ip)
config[CF_UNAUTH_TO_METHOD].valeur.integer == 2 &&
sens_timeout_exist(eth_mac_sender, arp_ip_rcpt, cap_id) == FALSE
)
) &&
// check if request is authorized
sens_exist(eth_mac_sender, arp_ip_rcpt, cap_id) == FALSE
){
#ifdef DEBUG_DETECT
logmsg(LOG_DEBUG, "[%s %d] -> DETECTED", __FILE__, __LINE__);
#endif
// add info for advanced timeouts
/*
if(config[CF_UNAUTH_TO_METHOD].valeur.integer == 2 &&
config[CF_ANTIFLOOD_INTER].valeur.integer != 0){
*/
if(config[CF_UNAUTH_TO_METHOD].valeur.integer == 2){
sens_timeout_add(eth_mac_sender, arp_ip_rcpt, cap_id);
}
// add info for simple timeout
eth_data->lastalert[4].tv_sec = current_t.tv_sec;
eth_data->lastalert[4].tv_usec = current_t.tv_usec;
send_alert(eth_mac_sender, arp_ip_sender, FLAG_UNAUTH_RQ,
&null_mac, arp_ip_rcpt, cap_id->device);
}
// =====================================
// error with ethernet mac and arp mac
// =====================================
#ifdef DEBUG_DETECT
logmsg(LOG_DEBUG,
"[%s %d] -> \"error with ethernet mac and arp mac\" Check ...",
__FILE__, __LINE__);
#endif
if(
// check if loggued
(
config[CF_LOG_BOGON].valeur.integer == TRUE ||
config[CF_ALERT_BOGON].valeur.integer == TRUE ||
config[CF_MOD_BOGON].valeur.integer == TRUE
) &&
// is an arp request
flag_is_arp == TRUE &&
// verif timeout
interval_ok(&(eth_data->lastalert[6])) == TRUE &&
// if the bitfield is not active
ISSET_MAC_ERROR(eth_data->alerts) == FALSE &&