Difference between pages "Package:Nftables" and "Flavors and Mix-ins/pt-br"

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(Created page with "{{Ebuild |Summary=Linux kernel (3.13+) firewall, NAT and packet mangling tools |CatPkg=net-firewall/nftables |Repository=Gentoo Portage Tree }} === What is nftables? === '''nf...")
 
 
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{{Ebuild
== Flavors (Sabores) ==
|Summary=Linux kernel (3.13+) firewall, NAT and packet mangling tools
|CatPkg=net-firewall/nftables
|Repository=Gentoo Portage Tree
}}
=== What is nftables? ===
'''nftables''' is the successor to [[iptables]]. It replaces the existing iptables, ip6tables, arptables and ebtables framework. It uses the Linux kernel and a new userspace utility called nft. nftables provides a compatibility layer for the ip(6)tables and framework.


==Introduction==
Um sistema pode possuir somente um flavor profile habilitado de cada vez. Os flavors a seguir estão disponíveis:
As with the iptables framework, nftables is build upon rules which specify the actions. These rules are attached to chains. A chain can contain a collection of rules and is registered into the netfilter hooks. Chains are stored inside tables. A table is specific for one of the layer 3 protocols. One of the main differences with iptables is that there are no predefined tables and chains anymore.


===Tables===
;minimal: Esse flavor define o flavor mínimo possível. Ele atualmente contem somente padrões para todos os flavors do Funtoo Linux flavors.
A table is nothing more than a container for your chains. With nftables there are no predefined tables (filter, raw, mangle...) anymore. You are free to recreate the iptables-like structure, but anything might do.
Currently there are 5 different families of tables:
* '''ip''': Used for IPv4 related chains;
* '''ip6''': Used for IPv6 related chains;
* '''arp''': Used for ARP related chains;
* '''bridge''': Used for bridging related chains;
* '''inet''': Mixed ipv4/ipv6 chains (kernel 3.14 and up).


It is not hard to recognize the old tables framework in these tables. The only new one is the inet table which is used for both IPv4 and IPv6 traffic. It should make firewalling for dual-stack hosts easier by combining the rules for IPv4 and IPv6.
;core: O core flavor é o minimal flavor mais as opções de USE razoáveis, e é utilizado para os builds do stage3.


===Chains===
;server: O server flavor é destinado para servidores, mas desta vez somente para rastrear core.
Chains are used to group together rules. As with the tables, nftables does not have any predefined chains. Chains are grouped in base and non-base types. Base chains are registered in one of the netfilter hooks. A base chain has a hook its registered with, a type and a priority.  Non-base chains are not attached to a hook and they don't see any traffic by default. They can be used to arrange a rule-set in a tree of chains.
There are currently three types of chains:
* '''filter''': for filtering packets
* '''route''': for rerouting packets
* '''nat''': for performing Network Address Translation. Only the first packet of a flow hits this chain, making it impossible to use it for filtering.
The hooks that can be used are:
* '''prerouting''': This is before the routing decision, all packets entering the machine hits this chain
* '''input''': All packets for the local system hits this hook
* '''forward''': Packets not for the local system, those that need to be forwarded hits this hook
* '''output''': Packets that originate from the local system pass this hook
* '''postrouting''': This hook is after the routing decision, all packets leaving the machine hits this chain
{{Note|The ARP address family only supports the input and output hook}}
{{Note|The bridge address family only seems to supports the input, forward and output hook}}


===Rules===
;workstation: O workstation flavor é um sistema desktop mínimo. Ele inclui o core flavor mais esses mix-ins: '''X''', '''audio''', '''dvd''', '''media''', '''console-extras'''
Rules specify which action has to be taken for which packets. Rules are attached to chains. Each rule can has an expression to match packets with and one or multiple actions when matching. Main differences with iptables is that it is possible to specify multiple actions and that by default counters are off. It must be specified explicitly in rules if you want packet- and byte-counters for a rule.
Each rule has a unique handle number by which it can be distinguished.
The following matches are available:
* '''ip''': IP protocol
* '''ip6''': IPv6 protocol
* '''tcp''': TCP protocol
* '''udp''': UDP protocol
* '''udplite''': UDP-lite protocol
* '''sctp''': SCTP protocol
* '''dccp''': DCCP protocol
* '''ah''': Authentication headers
* '''esp''': Encrypted security payload headers
* '''ipcomp''': IPcomp headers
* '''icmp''': icmp protocol
* '''icmpv6''': icmpv6 protocol
* '''ct''': Connection tracking
* '''meta''': meta properties such as interfaces


====Matches====
;desktop: O desktop flavor é um sistema desktop completo de recursos, menos ambiente desktop (adicione KDE, GNOME ou XFCE como um mix-in.) Ele inclui o '''workstation''' flavor mais '''printing''' support.
{|class=wikitable
| Match
| Arguments
| Description/Example
|-
| rowspan="11" | '''ip'''
| version
| Ip Header version
|-
| hdrlength
| IP header length
|-
| tos
|Type of Service
|-
| length
| Total packet length
|-
| id
| IP ID
|-
| frag-off
| Fragmentation offset
|-
| ttl
| Time to live
|-
| protocol
| Upper layer protocol
|-
| checksum
| IP header checksum
|-
| saddr
| Source address
|-
| daddr
| Destination address
|-
| rowspan="8" | '''ip6'''
| version
| IP header version
|-
| priority
|
|-
| flowlabel
| Flow label
|-
| length
| Payload length
|-
| nexthdr
| Next header type (Upper layer protocol number)
|-
| hoplimit
| Hop limit
|-
|saddr
| Source Address
|-
|daddr
| Destination Address
|-
| rowspan="9" | '''tcp'''
| sport
| Source port
|-
| dport
| Destination port
|-
| sequence
| Sequence number
|-
| ackseq
| Acknowledgement number
|-
| doff
| Data offset
|-
| flags
| TCP flags
|-
| window
| Window
|-
| checksum
| Checksum
|-
| urgptr
| Urgent pointer
|-
| rowspan="4" | '''udp'''
| sport
| Source port
|-
| dport
| destination port
|-
| length
| Total packet length
|-
| checksum
| Checksum
|-
| rowspan="4" | '''udplite'''
| sport
| Source port
|-
| dport
| destination port
|-
| cscov
| Checksum coverage
|-
| checksum
| Checksum
|-
| rowspan="4" |'''sctp'''
| sport
| Source port
|-
| dport
| destination port
|-
|vtag
|Verification tag
|-
| checksum
| Checksum
|-
| rowspan="2" |'''dccp'''
| sport
| Source port
|-
| dport
| destination port
|-
| rowspan="4" |'''ah'''
| nexthdr
| Next header protocol (Upper layer protocol)
|-
| hdrlength
| AH header length
|-
| spi
| Security Parameter Index
|-
| sequence
| Sequence Number
|-
| rowspan="2" | '''esp'''
| spi
| Security Parameter Index
|-
| sequence
| Sequence Number
|-
| rowspan="3" | '''ipcomp'''
| nexthdr
| Next header protocol (Upper layer protocol)
|-
| flags
| Flags
|-
| cfi
| Compression Parameter Index
|-
| '''icmp'''
| type
| icmp packet type
|-
| '''icmpv6'''
| type
| icmpv6 packet type
|-
|rowspan="12"|'''ct'''
|state
|State of the connection
|-
|direction
|Direction of the packet relative to the connection
|-
|status
|Status of the connection
|-
|mark
|Connection mark
|-
|expiration
|Connection expiration time
|-
|helper
|Helper associated with the connection
|-
|l3proto
|Layer 3 protocol of the connection
|-
|saddr
|Source address of the connection for the given direction
|-
|daddr
|Destination address of the connection for the given direction
|-
|protocol
|Layer 4 protocol of the connection for the given direction
|-
|proto-src
|Layer 4 protocol source for the given direction
|-
|proto-dst
|Layer 4 protocol destination for the given direction
|-
| rowspan="13" | '''meta'''
| length
| Length of the packet in bytes: ''meta length > 1000''
|-
| protocol
| ethertype protocol: ''meta protocol vlan''
|-
| priority
| TC packet priority
|-
| mark
| Packet mark
|-
| iif
| Input interface index
|-
| iifname
| Input interface name
|-
| iiftype
| Input interface type
|-
| oif
| Output interface index
|-
| oifname
| Output interface name
|-
| oiftype
| Output interface hardware type
|-
| skuid
| UID associated with originating socket
|-
| skgid
| GID associated with originating socket
|-
| rtclassid
| Routing realm
|-
|}
====Statements====
Statements represent the action to be performed when the rule matches. They exist in two kinds: Terminal statements, unconditionally terminate the evaluation of the current rules and non-terminal statements that either conditionally or never terminate the current rules. There can be an arbitrary amount of non-terminal statements, but there must be only a single terminal statement.
The terminal statements can be:
* '''accept''': Accept the packet and stop the ruleset evaluation.
* '''drop''': Drop the packet and stop the ruleset evaluation.
* '''reject''': Reject the packet with an icmp message
* '''queue''': Queue the packet to userspace and stop the ruleset evaluation.
* '''continue''':
* '''return''': Return from the current chain and continue at the next rule of the last chain. In a base chain it is equivalent to accept
* '''jump <chain>''': Continue at the first rule of <chain>. It will continue at the next rule after a return statement is issued
* '''goto <chain>''': Similar to jump, but after the new chain the evaluation will continue at the last chain instead of the one containing the goto statement


== Installing nftables ==
== Mix-ins ==
=== Kernel ===
These kernel options must be set:


[*] Networking support  --->
Um sistema pode ter quaisquer número de mix-ins habilitados de cada vês. Os mix-ins a seguir estão disponíveis:
    Networking options  --->
        [*] Network packet filtering framework (Netfilter)  --->
            Core Netfilter Configuration  --->
                <M> Netfilter nf_tables support
                <M>  Netfilter nf_tables IPv6 exthdr module
                <M>  Netfilter nf_tables meta module
                <M>  Netfilter nf_tables conntrack module
                <M>  Netfilter nf_tables rbtree set module
                <M>  Netfilter nf_tables hash set module
                <M>  Netfilter nf_tables counter module
                <M>  Netfilter nf_tables log module
                <M>  Netfilter nf_tables limit module
                <M>  Netfilter nf_tables nat module
                <M>  Netfilter x_tables over nf_tables module
            IP: Netfilter Configuration  --->
                <M> IPv4 nf_tables support
                <M>  nf_tables IPv4 reject support
                <M>  IPv4 nf_tables route chain support
                <M>  IPv4 nf_tables nat chain support
            IPv6: Netfilter Configuration  --->
                <M> IPv6 nf_tables support
                <M>  IPv6 nf_tables route chain support
                <M>  IPv6 nf_tables nat chain support
            <M>  Ethernet Bridge nf_tables support


=== Emerging ===
;audio: Habilita as configurações do núcleo (core) relacionadas a áudio, atualmente relacionadas ao ALSA.
To install nftables, run the following command:
<console>
###i## emerge net-firewall/nftables
</console>


;console-extras: Habilita coisas que são boas de ter para sistemas de somente console (console-only systems). Atualmente habilitando gpm em USE.


== OpenRC configuration ==
;dvd: Configurações USE relacionadas a drives óticos -- Uso de CDR/DVD-ROM/RW.
Don't forget to add nftables service to startup:
<console>
###i## rc-update add nftables default
</console>


You cannot use iptables and nft to perform NAT at the same time. So make sure that the iptable_nat module is unloaded. Remove iptables_nat module:
;gnome: Configurações do USE e do package.use necessárias para instalar e utilizar (merge) o GNOME.
<console>
###i## rmmod iptable_nat
</console>


Start nftables:
;hardened: Habilita suporte hardened.
<console>
###i## /etc/init.d/nftables start
</console>


;kde: Configurações de USE e de package.use necessárias para instalar e utilizar (merge) o KDE.


== Using nftables ==
;media: USE settings related to audio/video media encoding. Can be for desktops or servers.
All nftable commands are done with the nft ultility from {{Package|net-firewall/nftables}}.
===Tables===
====Creating tables====
The following command adds a table called filter for the ip(v4) layer
<console>
###i## nft add table ip filter
</console>
Likewise a table for arp can be created with
<console>
###i## nft add table arp filter
</console>
{{Note|The name "filter" used here is completly arbitrary. It could have any name}}
====Listing tables====
The following command lists all tables for the ip(v4) layer
<console>
###i## nft list tables ip
</console>
<pre>
table filter
</pre>
The contents of the table filter can be listed with:
<console>
###i## nft list table ip filter
</console>
<pre>
table ip filter {
        chain input {
                type filter hook input priority 0;
                ct state established,related accept
                iifname "lo" accept
                ip protocol icmp accept
                drop
        }
}
</pre>
using -a with the nft command, it shows the handle of each rule. Handles are used for various operations on specific rules:
<console>
###i## nft -a list table ip filter
</console>
<pre>
table ip filter {
        chain input {
                type filter hook input priority 0;
                ct state established,related accept # handle 2
                iifname "lo" accept # handle 3
                ip protocol icmp accept # handle 4
                drop # handle 5
        }
}
</pre>


====Deleting tables====
;print: Habilita a capacidade de impressão (printing).
The following command deletes the table called filter for the ip(v4) layer:
<console>
###i## nft delete table ip filter
</console>
===chains===
====Adding chains====
The following command adds a chain called input to the ip filter table and registered to the input hook with priority 0. It is of the type filter.
<console>
###i## nft add chain ip filter input { type filter hook input priority 0 \; }
</console>
{{Note|If You're running this command from Bash you need to escape the semicolon}}
A non-base chain can be added by not specifying the chain configurations between the curly braces.


====Removing chains====
;rhel5-compat: Configurações necessárias para a execução de um sistema que utiliza um kernel baseado no Red Hat Enterprise Linux 5-based kernel.
The following command deletes the chain called input
<console>
###i## nft delete chain ip filter input
</console>
{{Note|Chains can only be deleted if there are no rules in them.}}
===rules===
====Adding rules====
The following command adds a rule to the chain called input, on the ip filter table, dropping all traffic to port 80:
<console>
###i## nft add rule ip filter input tcp dport 80 drop
</console>
====Deleting Rules====
To delete a rule, you first need to get the handle number of the rule. This can be done by using the -a flag on nft:
<console>
###i## nft  rule ip filter input tcp dport 80 drop
</console>
<pre>
table ip filter {
        chain input {
                type filter hook input priority 0;
                tcp dport http drop # handle 2
        }
}
</pre>
It is then possible to delete the rule with:
<console>
###i## nft delete rule ip filter input handle 2
</console>
== Management ==
=== Backup ===
You can also backup your rules:
<console>
###i## echo "nft flush ruleset" > backup.nft
</console>


<console>
;vmware-guest: Configurações relacionadas ao uso do Funtoo Linux como um convidado (guest) na máquina virtual VMWare.
###i## nft list ruleset >> backup.nft
</console>


=== Restoration ===
;X: Configurações relacionadas ao sistema X Window e ao suporte a hardware.
And load it atomically:
<console>
###i## nft -f backup.nft
</console>


== OpenRC configuration ==
;xfce: Configurações USE necessárias para instalação e utilização (merging) do XFCE.


Don't forget to add nftables service to startup:
[[Category:Portage]]
<console>
[[Category:Funtoo features]]
###i## rc-update add nftables default
</console>
== Init script - firewall nftables like a firewall iptables ==
<pre>
#!/sbin/runscript
#      Raphael Bastos aka coffnix        #
#      Init Script for Funtoo Linux      #
##########################################
 
depend() {
        need net
        need nftables
        }
 
start(){
##################### PARTE 1 #####################
ebegin "Starting Firewall NFTables"
 
#######################################################################
### Incompatibilities ###
# You cannot use iptables and nft to perform NAT at the same time. So make sure that the iptable_nat module is unloaded
rmmod iptable_nat
 
#######################################################################
 
echo 1 > /proc/sys/net/ipv4/ip_forward
echo 1 > /proc/sys/net/ipv4/ip_dynaddr
echo 1 > /proc/sys/net/ipv4/conf/all/rp_filter
for f in /proc/sys/net/ipv4/conf/*/rp_filter ; do echo 1 > $f ; done
 
#######################################################################
 
iptables -t nat -F
 
#######################################################################
 
# ipv4
nft -f /etc/nftables/ipv4-filter
 
# ipv4 nat
nft -f /etc/nftables/ipv4-nat
 
# ipv6
nft -f /etc/nftables/ipv6-filter
 
# Rules firewall NTFtables
nft -f /etc/nftables/firewall.rules
 
#######################################################################
 
}
 
stop(){
ebegin "Stoping Firewall NFTables"
 
#######################################################################
 
#iptables -t nat -F
NFT=nft
FAMILIES="ip ip6 arp bridge"
 
for FAMILY in $FAMILIES; do
  TABLES=$($NFT list tables $FAMILY | grep "^table\s" | cut -d' ' -f2)
 
  for TABLE in $TABLES; do
    CHAINS=$($NFT list table $FAMILY $TABLE | grep "^\schain\s" | cut -d' ' -f2)
 
    for CHAIN in $CHAINS; do
      echo "Flushing chain: $FAMILY->$TABLE->$CHAIN"
      $NFT flush chain $FAMILY $TABLE $CHAIN
      $NFT delete chain $FAMILY $TABLE $CHAIN
    done
 
    echo "Flushing table: $FAMILY->$TABLE"
    $NFT flush table $FAMILY $TABLE
    $NFT delete table $FAMILY $TABLE
  done
done
}
 
status(){
nft list ruleset
}
 
# End
</pre>
 
[[Category:System]]
[[Category:First Steps]]
{{EbuildFooter}}

Revision as of 20:19, March 25, 2015

Flavors (Sabores)

Um sistema pode possuir somente um flavor profile habilitado de cada vez. Os flavors a seguir estão disponíveis:

minimal
Esse flavor define o flavor mínimo possível. Ele atualmente contem somente padrões para todos os flavors do Funtoo Linux flavors.
core
O core flavor é o minimal flavor mais as opções de USE razoáveis, e é utilizado para os builds do stage3.
server
O server flavor é destinado para servidores, mas desta vez somente para rastrear core.
workstation
O workstation flavor é um sistema desktop mínimo. Ele inclui o core flavor mais esses mix-ins: X, audio, dvd, media, console-extras
desktop
O desktop flavor é um sistema desktop completo de recursos, menos ambiente desktop (adicione KDE, GNOME ou XFCE como um mix-in.) Ele inclui o workstation flavor mais printing support.

Mix-ins

Um sistema pode ter quaisquer número de mix-ins habilitados de cada vês. Os mix-ins a seguir estão disponíveis:

audio
Habilita as configurações do núcleo (core) relacionadas a áudio, atualmente relacionadas ao ALSA.
console-extras
Habilita coisas que são boas de ter para sistemas de somente console (console-only systems). Atualmente habilitando gpm em USE.
dvd
Configurações USE relacionadas a drives óticos -- Uso de CDR/DVD-ROM/RW.
gnome
Configurações do USE e do package.use necessárias para instalar e utilizar (merge) o GNOME.
hardened
Habilita suporte hardened.
kde
Configurações de USE e de package.use necessárias para instalar e utilizar (merge) o KDE.
media
USE settings related to audio/video media encoding. Can be for desktops or servers.
print
Habilita a capacidade de impressão (printing).
rhel5-compat
Configurações necessárias para a execução de um sistema que utiliza um kernel baseado no Red Hat Enterprise Linux 5-based kernel.
vmware-guest
Configurações relacionadas ao uso do Funtoo Linux como um convidado (guest) na máquina virtual VMWare.
X
Configurações relacionadas ao sistema X Window e ao suporte a hardware.
xfce
Configurações USE necessárias para instalação e utilização (merging) do XFCE.