hello

I have not explained the full details on the list in my previous email. The 
point is that I noted that spam source ips keep repeating 4-5 times immediately 
one after another and there are 100s of such instances. i wish to block those 
only and not all ips. So it will require some coding using a mysql database.

secondly you say "We (a med/large ISP) block any email from Dynamic IP 
addresses,"

my question is how do you determine whether an ip is in an Dynamic IP address 
pool.

rajesh

---------- Original Message ----------------------------------
From: "Brandon Macmillan" <[EMAIL PROTECTED]>
Date:  Wed, 22 Aug 2007 15:49:44 -0700

>Surely you are joking? So the first time that an AOL user sends you a
>single spam email you want to stop receiving email from ALL AOL users?
>Talk about swatting a fly with a flamethrower. Or do you want to block
>it based upon the sender's original IP address from the message headers?
>You know that spammers usually forge those? You're just going to end up
>blocking the large legitimate email providers and not stop the army of
>spam zombies that are out there. You would be better off implementing
>something like a DNSBL or DHUL list on your firewall. We (a med/large
>ISP) block any email from Dynamic IP addresses, this greatly cuts down
>on the spam zombie traffic.
>
>Also remember that with IP tables the longer your table is the more
>"hops" that the packets must pass through before hitting your -j ACCEPT
>rule, if you implement it as you suggested below your IP Table will grow
>and grow and grow and your network performance and latency will get
>worse and worse and worse.
>
>Brandon
>
>-----Original Message-----
>From: [EMAIL PROTECTED]
>[mailto:[EMAIL PROTECTED] On Behalf Of Raj
>Sent: Wednesday, August 22, 2007 12:09 PM
>To: [email protected]
>Subject: [dspam-users] blocking ips of spam source in firewall
>
>Hi
>
>i want to block the ips of spam sources immediately as soon as dspam
>detects them as spam
>
>dspam does a logs these ips correctly into my /var/log/maillog file so i
>know that things are working correctly
>
>on the linux console i use the following command to block an ip address 
>
>/sbin/iptables -I INPUT -s 111.111.111.111 -j DROP
>
>this code snippet below is from the dspam source ie dspam.c file in the
>src directory
>
>the variable called "ip" contains the ip address which is logged to the
>maillog file
>
>i understand that just a single line is required after the last line to
>execute the command but i am not sure of the C syntax
>
>can someone help me ?
>
>###########
>
>int tracksource(DSPAM_CTX *CTX) {
>  char ip[32];
>
>  if (!dspam_getsource (CTX, ip, sizeof (ip)))
>  {
>    if (CTX->totals.innocent_learned + CTX->totals.innocent_classified >
>2500) {
>      if (CTX->result == DSR_ISSPAM && 
>          _ds_match_attribute(agent_config, "TrackSources", "spam")) {
>        FILE *file;
>        char dropfile[MAX_FILENAME_LENGTH];
>        LOG (LOG_INFO, "spam detected from %s", ip);
>
>
>###########
>
>thanks
>raj
>
>!DSPAM:30,46cc84d5155591285519399!
>
>

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