Re: Does Qmail have support for Dynamic IP Spam Sources List

Russell Nelson ([EMAIL PROTECTED]) wrote:
: Yusuf Goolamabbas writes:
:  > Hi, The following web site 
:  > 
:  > http://www.imrss.org/dssl/
:  > 
:  > seems to have a mechanism to prevent spammers from sending directly
:  > from dial-up lines. The site has no docs on how to get qmail
:  > integrated with it, Anybody have any idea

: Ought to work just fine using rblsmtpd.  Look on koobera (as usual).

This might answer.

/*
  Filter connections from dial-up hosts, based on patterns.txt
  which is a list of regular expressions of dial-up ip hostnames
  obtainable from www.imrss.org/dssl/
  To build this, you must have already built djb's cdb package.
  Compile with something like:
    cc dssl-filter.c -o dssl-filter -I<path> -L<path> -lcdb
  where <path> is the path to the cdb source directory.
  To use this, first build the cdb version of the patterns.txt file:
  { while read dom hos; do
    echo "+${#dom},${#hos}:${dom}->${hos}"
  done; echo; } <patterns.txt |cdbmake cdbfile cdbtmp
  (assuming a fairly modern sh-type shell.)
  Make sure patterns.txt does not contain blank lines.
  To run this, insert into standard djb exec chain:
    tcpserver 0 smtp dssl-filter cdbfile qmail-smtpd
  The filter requires TCPREMOTEHOST to be set if it is to do any
  filtering, so don't use option -H to tcpserver.
  No warranty, no restrictions, YMMV.
  -harold
 */

#include <unistd.h>
#include <fcntl.h>
#include <stdlib.h>
#include <regex.h>

#include <uint32.h>
#include <cdb.h>

#define FLAGS (REG_EXTENDED|REG_ICASE|REG_NOSUB)

int cdbfd;

char *
lookup(char * key, int len)
{
  uint32 dlen;
  static char buf[256];

  if( 1 != cdb_seek(cdbfd, key, len, &dlen) )return(0);
  if( dlen > 255 )return(0);
  if( dlen != read(cdbfd, buf, dlen) )return(0);
  buf[dlen] = '\0';
  return(buf);
}

int
main(int argc, char ** argv)
{
  char * remotehost;
  char * dom;
  char * hos;
  regex_t regex;
  int len;

  if( argc < 3 )_exit(1);
  if( ! (remotehost = getenv("TCPREMOTEHOST")) )goto done;
  if( -1 == (cdbfd = open(argv[1], O_RDONLY)) )goto done;

  for(dom = remotehost; *dom; dom++);
  for(len = 0, dom--; dom > remotehost; dom--, len++)
    if( '.' == *dom )
      if( (hos = lookup(dom + 1, len)) ){
        *dom = '\0';
        if( 0 == regcomp(&regex, hos, FLAGS) )
          if( 0 == regexec(&regex, remotehost, 0, 0, 0) )
            exit(3);
        *dom = '.';
      }

done:
  execvp(argv[2], argv + 2);
  _exit(128);
}