/**
* \brief Add IPv4 header data, to be stored in the Additional Data
* field of the IDMEF alert (see section 4.2.4.6 of RFC 4765).
*
* \return 0 if ok
*/
static int PacketToDataV4(Packet *p, PacketAlert *pa, idmef_alert_t *alert)
{
SCEnter();
AddIntData(alert, "ip_ver", IPV4_GET_RAW_VER(p->ip4h));
AddIntData(alert, "ip_hlen", IPV4_GET_RAW_HLEN(p->ip4h));
AddIntData(alert, "ip_tos", IPV4_GET_RAW_IPTOS(p->ip4h));
AddIntData(alert, "ip_len", ntohs(IPV4_GET_RAW_IPLEN(p->ip4h)));
AddIntData(alert, "ip_id", ntohs(IPV4_GET_RAW_IPID(p->ip4h)));
AddIntData(alert, "ip_off", ntohs(IPV4_GET_RAW_IPOFFSET(p->ip4h)));
AddIntData(alert, "ip_ttl", IPV4_GET_RAW_IPTTL(p->ip4h));
AddIntData(alert, "ip_proto", IPV4_GET_RAW_IPPROTO(p->ip4h));
AddIntData(alert, "ip_sum", ntohs(p->ip4h->ip_csum));
SCReturnInt(0);
}
/**
* Note, this is the IP header, plus a bit of the original packet, not the whole thing!
*/
int DecodePartialIPV4( Packet* p, uint8_t* partial_packet, uint16_t len )
{
/** Check the sizes, the header must fit at least */
if (len < IPV4_HEADER_LEN) {
SCLogDebug("DecodePartialIPV4: ICMPV4_IPV4_TRUNC_PKT");
ENGINE_SET_INVALID_EVENT(p, ICMPV4_IPV4_TRUNC_PKT);
return -1;
}
IPV4Hdr *icmp4_ip4h = (IPV4Hdr*)partial_packet;
/** Check the embedded version */
if (IPV4_GET_RAW_VER(icmp4_ip4h) != 4) {
/** Check the embedded version */
SCLogDebug("DecodePartialIPV4: ICMPv4 contains Unknown IPV4 version "
"ICMPV4_IPV4_UNKNOWN_VER");
ENGINE_SET_INVALID_EVENT(p, ICMPV4_IPV4_UNKNOWN_VER);
return -1;
}
/** We need to fill icmpv4vars */
p->icmpv4vars.emb_ipv4h = icmp4_ip4h;
/** Get the IP address from the contained packet */
p->icmpv4vars.emb_ip4_src = IPV4_GET_RAW_IPSRC(icmp4_ip4h);
p->icmpv4vars.emb_ip4_dst = IPV4_GET_RAW_IPDST(icmp4_ip4h);
p->icmpv4vars.emb_ip4_hlen=IPV4_GET_RAW_HLEN(icmp4_ip4h) << 2;
switch (IPV4_GET_RAW_IPPROTO(icmp4_ip4h)) {
case IPPROTO_TCP:
if (len >= IPV4_HEADER_LEN + TCP_HEADER_LEN ) {
p->icmpv4vars.emb_tcph = (TCPHdr*)(partial_packet + IPV4_HEADER_LEN);
p->icmpv4vars.emb_sport = ntohs(p->icmpv4vars.emb_tcph->th_sport);
p->icmpv4vars.emb_dport = ntohs(p->icmpv4vars.emb_tcph->th_dport);
p->icmpv4vars.emb_ip4_proto = IPPROTO_TCP;
SCLogDebug("DecodePartialIPV4: ICMPV4->IPV4->TCP header sport: "
"%"PRIu8" dport %"PRIu8"", p->icmpv4vars.emb_sport,
p->icmpv4vars.emb_dport);
} else if (len >= IPV4_HEADER_LEN + 4) {
/* only access th_sport and th_dport */
TCPHdr *emb_tcph = (TCPHdr*)(partial_packet + IPV4_HEADER_LEN);
p->icmpv4vars.emb_tcph = NULL;
p->icmpv4vars.emb_sport = ntohs(emb_tcph->th_sport);
p->icmpv4vars.emb_dport = ntohs(emb_tcph->th_dport);
p->icmpv4vars.emb_ip4_proto = IPPROTO_TCP;
SCLogDebug("DecodePartialIPV4: ICMPV4->IPV4->TCP partial header sport: "
"%"PRIu8" dport %"PRIu8"", p->icmpv4vars.emb_sport,
p->icmpv4vars.emb_dport);
} else {
SCLogDebug("DecodePartialIPV4: Warning, ICMPV4->IPV4->TCP "
"header Didn't fit in the packet!");
p->icmpv4vars.emb_sport = 0;
p->icmpv4vars.emb_dport = 0;
}
break;
case IPPROTO_UDP:
if (len >= IPV4_HEADER_LEN + UDP_HEADER_LEN ) {
p->icmpv4vars.emb_udph = (UDPHdr*)(partial_packet + IPV4_HEADER_LEN);
p->icmpv4vars.emb_sport = ntohs(p->icmpv4vars.emb_udph->uh_sport);
p->icmpv4vars.emb_dport = ntohs(p->icmpv4vars.emb_udph->uh_dport);
p->icmpv4vars.emb_ip4_proto = IPPROTO_UDP;
SCLogDebug("DecodePartialIPV4: ICMPV4->IPV4->UDP header sport: "
"%"PRIu8" dport %"PRIu8"", p->icmpv4vars.emb_sport,
p->icmpv4vars.emb_dport);
} else {
SCLogDebug("DecodePartialIPV4: Warning, ICMPV4->IPV4->UDP "
"header Didn't fit in the packet!");
p->icmpv4vars.emb_sport = 0;
p->icmpv4vars.emb_dport = 0;
}
break;
case IPPROTO_ICMP:
if (len >= IPV4_HEADER_LEN + ICMPV4_HEADER_LEN ) {
p->icmpv4vars.emb_icmpv4h = (ICMPV4Hdr*)(partial_packet + IPV4_HEADER_LEN);
p->icmpv4vars.emb_sport = 0;
p->icmpv4vars.emb_dport = 0;
p->icmpv4vars.emb_ip4_proto = IPPROTO_ICMP;
SCLogDebug("DecodePartialIPV4: ICMPV4->IPV4->ICMP header");
}
break;
}
/* debug print */
#ifdef DEBUG
char s[16], d[16];
PrintInet(AF_INET, &(p->icmpv4vars.emb_ip4_src), s, sizeof(s));
PrintInet(AF_INET, &(p->icmpv4vars.emb_ip4_dst), d, sizeof(d));
SCLogDebug("ICMPv4 embedding IPV4 %s->%s - PROTO: %" PRIu32 " ID: %" PRIu32 "", s,d,
IPV4_GET_RAW_IPPROTO(icmp4_ip4h), IPV4_GET_RAW_IPID(icmp4_ip4h));
#endif
return 0;
}