On 08/23/2018 11:10 AM, Rick Stevens wrote:
On 08/22/2018 06:00 PM, ToddAndMargo wrote:
> On 08/22/2018 04:37 PM, Ed Greshko wrote:
>> On 08/23/18 06:47, ToddAndMargo wrote:
>>> Hi All,
>>>
>>> My iptables firewall ported from RHEL won't connect to ftp sites
>>> and throws this error (written by me years ago):
>>>
>>>
>>> WARNING: active FTP rules have been selected but one or
>>> more necessary modules have not been detected
>>>
>>> In /etc/sysconfig/iptables-config, you must add ip_nat_ftp
>>> and ip_conntrack_ftp to IPTABLES_MODULES. Delimiter is a
>>> space. For example:
>>> IPTABLES_MODULES=ip_nat_ftp ip_conntrack_ftp
>>>
>>> To load changes, use:
>>> # /etc/rc.d/init.d/iptables restart
>>> # systemctl restart iptables
>>>
>>> To check if modules are loaded, use
>>> lsmod
>>>
>>>
>>> 1) is Fedora doing FTP differently in iptables?
>>>
>>> 2) where do I find
>>> ip_nat_ftp
>>> ip_conntrack_ftp
>>> now a days?
>>>
>>
>> I can't locate my notes at the moment. But I believe the way things
>> are done in the
>> netfilter framework has changed.
>>
>> If memory servers me the nf_conntrack_ipv4 will load, as needed, the
>> necessary
>> "helper". I use the standard firewall and these modules are loaded.
>>
>> xt_conntrack 16384 21
>> nf_conntrack_ipv6 16384 12
>> nf_defrag_ipv6 20480 1 nf_conntrack_ipv6
>> nf_conntrack_ipv4 16384 11
>> nf_defrag_ipv4 16384 1 nf_conntrack_ipv4
>> nf_conntrack 147456 6
>> xt_conntrack,nf_conntrack_ipv6,nf_conntrack_ipv4,nf_nat,nf_nat_ipv6,nf_nat_ipv4
>>
>> libcrc32c 16384 2 nf_conntrack,nf_nat
>>
>> and ftp works fine.
>>
>> ip_nat_ftp does not exist on my system. But I do have nf_conntrack_ftp.
>
> I see nf_conntrack_ftp inserted
>
> # lsmod | grep nf_conntrack_ftp
> nf_conntrack_ftp 20480 1 nf_nat_ftp
> nf_conntrack 147456 9
>
xt_conntrack,nf_nat_masquerade_ipv4,nf_conntrack_ipv4,nf_nat,nf_nat_ftp,ipt_MASQUERADE,nf_nat_ipv4,xt_helper,nf_conntrack_ftp
>
>
>
> But it is not following the high ports that ftp uses:
>
> Aug 22 16:12:09 rn6 kernel: dsl-out Everything Else IN= OUT=eno2
> SRC=192.168.xxx.yyy DST=208.106.xxx.yyy LEN=60 TOS=0x00 PREC=0x00 TTL=64
> ID=25991 DF PROTO=TCP SPT=59698 DPT=21023 WINDOW=29200 RES=0x00 SYN URGP=0
Perhaps I missed this, but are you trying to set up an FTP _server_ on
your machine or using it as an FTP client? The firewall rules for an
FTP server would be significantly different--especially if you wish to
provide both passive and normal FTP operations.
Just ftp client and I want to support both active and passive mode