Snort mailing list archives
Logging to DB it's done differently than to a file.
From: "Bruno G. San Alejo" <bgonzalez () polar es>
Date: Wed, 04 Mar 2009 15:14:26 +0100
Hi, I have found how Snort logs to a file and to the DB and maybe it's the cause of why I seem to have ICMP redirect packages with the wrong gateway's IP. To make a really long story short, when logging to a file Snort uses the pcap_dump() function than (if I'm not mistaken) logs the packet as it gets it from Snort. When logging to the DB, the ICMP packet gets parsed and the insert is as follows in the Database() func: ret = SnortSnprintf(query->val, MAX_QUERY_LENGTH, "INSERT INTO " "icmphdr (sid, cid, icmp_type, icmp_code, icmp_csum, icmp_id, icmp_seq) " "VALUES (%u,%u,%u,%u,%u,%u,%u)", data->shared->sid, data->shared->cid, p->icmph->type, p->icmph->code, ntohs(p->icmph->csum), ntohs(p->icmph->s_icmp_id), ntohs(p->icmph->s_icmp_seq)); Note the references to p->icmph->s_icmp_seq and p->icmph->s_icmp_id. Now, ICMP redirect packets don't have those fields, they have the gateway's IP instead. Since the packets are not "decoded" but the actual packet is laid over the Packet struct which contains unions, those fields have data, though not valid one. Maybe the IP for the gateway is there. The result is that when I see the Snort logged packets in pcap format, they are correct, but the ones seen through BASE or saved to pcap through BASE, are not. The ones shown through BASE have wrong gateway's IPs. Also, BASE gets the gateway's IP from someplace else which I think is not the IP. So, that is an issue also. I'm sorry to be a pain in the neck with this issue but I would like someone to correct me or maybe there is something to be solved in here. Thanks. ------------------------------------------------------------------------------ Open Source Business Conference (OSBC), March 24-25, 2009, San Francisco, CA -OSBC tackles the biggest issue in open source: Open Sourcing the Enterprise -Strategies to boost innovation and cut costs with open source participation -Receive a $600 discount off the registration fee with the source code: SFAD http://p.sf.net/sfu/XcvMzF8H _______________________________________________ Snort-users mailing list Snort-users () lists sourceforge net Go to this URL to change user options or unsubscribe: https://lists.sourceforge.net/lists/listinfo/snort-users Snort-users list archive: http://www.geocrawler.com/redir-sf.php3?list=snort-users
Current thread:
- Logging to DB it's done differently than to a file. Bruno G. San Alejo (Mar 04)
- Re: [Snort-devel] Logging to DB it's done differently than to a file. Steven Sturges (Mar 04)
- Re: [Snort-devel] Logging to DB it's done differently than to a file. Bruno G. San Alejo (Mar 04)
- Re: [Snort-devel] Logging to DB it's done differently than to a file. Steven Sturges (Mar 04)