summaryrefslogtreecommitdiffstats
path: root/include
Commit message (Collapse)AuthorAgeFilesLines
* src: fix sub-byte protocol header definitionsPablo Neira Ayuso2015-12-143-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Update bitfield definitions to match according to the way they are expressed in RFC and IEEE specifications. This required a bit of update for c3f0501 ("src: netlink_linearize: handle sub-byte lengths"). >From the linearize step, to calculate the shift based on the bitfield offset, we need to obtain the length of the word in bytes: len = round_up(expr->len, BITS_PER_BYTE); Then, we substract the offset bits and the bitfield length. shift = len - (offset + expr->len); From the delinearize, payload_expr_trim() needs to obtain the real offset through: off = round_up(mask->len, BITS_PER_BYTE) - mask_len; For vlan id (offset 12), this gets the position of the last bit set in the mask (ie. 12), then we substract the length we fetch in bytes (16), so we obtain the real bitfield offset (4). Then, we add that to the original payload offset that was expressed in bytes: payload_offset += off; Note that payload_expr_trim() now also adjusts the payload expression to its real length and offset so we don't need to propagate the mask expression. Reported-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* payload: add payload statementPatrick McHardy2015-11-252-0/+28
| | | | | | | | | Add support for payload mangling using the payload statement. The syntax is similar to the other data changing statements: nft filter output tcp dport set 25 Signed-off-by: Patrick McHardy <kaber@trash.net>
* proto: add checksum key information to struct proto_descPatrick McHardy2015-11-251-0/+2
| | | | | | | The checksum key is used to determine the correct position where to update the checksum for the payload statement. Signed-off-by: Patrick McHardy <kaber@trash.net>
* rule: move comment out of handlePatrick McHardy2015-11-151-2/+2
| | | | | | The comment does not belong to the handle, it belongs to the rule. Signed-off-by: Patrick McHardy <kaber@trash.net>
* src: allow filtering on L2 header in inet familyFlorian Westphal2015-11-061-0/+2
| | | | | | | | | | | | | | | | | | Error: conflicting protocols specified: inet vs. ether tcp dport 22 iiftype ether ether saddr 00:0f:54:0c:11:4 ^^^^^^^^^^^ This allows the implicit inet proto dependency to get replaced by an ethernet one. This is possible since by the time we detect the conflict the meta dependency for the network protocol has already been added. So we only need to add another dependency on the Linklayer frame type. Closes: http://bugzilla.netfilter.org/show_bug.cgi?id=981 Acked-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Florian Westphal <fw@strlen.de>
* src: add interface wildcard matchingPablo Neira Ayuso2015-11-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Contrary to iptables, we use the asterisk character '*' as wildcard. # nft --debug=netlink add rule test test iifname eth\* ip test test [ meta load iifname => reg 1 ] [ cmp eq reg 1 0x00687465 ] Note that this generates an optimized comparison without bitwise. In case you want to match a device that contains an asterisk, you have to escape the asterisk, ie. # nft add rule test test iifname eth\\* The wildcard string handling occurs from the evaluation step, where we convert from: relational / \ / \ meta value oifname eth* to: relational / \ / \ meta prefix ofiname As Patrick suggested, this not actually a wildcard but a prefix since it only applies to the string when placed at the end. More comments: * This relaxes the left->size > right->size from netlink_parse_cmp() for strings since the optimization that this patch applies may now result in bogus errors. * This patch can be later on extended to apply a similar optimization to payload expressions when: expr->len % BITS_PER_BYTE == 0 For meta and ct, the kernel checks for the exact length of the attributes (it expects integer 32 bits) so we can't do it unless we relax that. * Wildcard strings are not supported from sets and maps yet. Error reporting is not very good at this stage since expr_evaluate_prefix() doesn't have enough context (ctx->set is NULL, the set object is currently created later after evaluating the lhs and rhs of the relational). I'll be following up on this later. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: Add command "replace" for rulesCarlos Falgueras García2015-11-023-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | Modify the parser and add necessary functions to provide the command "nft replace rule <ruleid_spec> <new_rule>" Example of use: # nft list ruleset -a table ip filter { chain output { ip daddr 8.8.8.7 counter packets 0 bytes 0 # handle 3 } } # nft replace rule filter output handle 3 ip daddr 8.8.8.8 counter # nft list ruleset -a table ip filter { chain output { ip daddr 8.8.8.8 counter packets 0 bytes 0 # handle 3 } } Signed-off-by: Carlos Falgueras García <carlosfg@riseup.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: add `list chains' commandPablo Neira Ayuso2015-10-121-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | # nft list chains table ip filter { chain test1 { } chain test2 { } chain input { type filter hook input priority 0; policy accept; } } table ip6 filter { chain test1 { } chain input { type filter hook input priority 0; policy accept; } } You can also filter out per family: # nft list chains ip table ip x { chain y { } chain xz { } chain input { type filter hook input priority 0; policy accept; } } # nft list chains ip6 table ip6 filter { chain x { } chain input { type filter hook input priority 0; policy accept; } } This command only shows the chain declarations, so the content (the definition) is omitted. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
* src: add dup statement supportPablo Neira Ayuso2015-09-303-0/+26
| | | | | | | | | | This allows you to clone packets to destination address, eg. ... dup to 172.20.0.2 ... dup to 172.20.0.2 device eth1 ... dup to ip saddr map { 192.168.0.2 : 172.20.0.2, ... } device eth1 Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: add burst parameter to limitPablo Neira Ayuso2015-09-232-0/+4
| | | | | | | | | | | ... limit rate 1024 mbytes/second burst 10240 bytes ... limit rate 1/second burst 3 packets This parameter is optional. You need a Linux kernel >= 4.3-rc1. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: add per-bytes limitPablo Neira Ayuso2015-09-233-0/+14
| | | | | | | | | | This example show how to accept packets below the ratelimit: ... limit rate 1024 mbytes/second counter accept You need a Linux kernel >= 4.3-rc1. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* nft: support listing expressions that use non-byte header fieldsFlorian Westphal2015-09-181-0/+3
| | | | | | | This allows to list rules that check fields that are not aligned on byte boundary. Signed-off-by: Florian Westphal <fw@strlen.de>
* nft: allow stacking vlan header on top of ethernetFlorian Westphal2015-09-181-0/+4
| | | | | | | | | | | | | | | | | | | | currently 'vlan id 42' or even 'vlan type ip' doesn't work since we expect ethernet header but get vlan. So if we want to add another protocol header to the same base, we attempt to figure out if the new header can fit on top of the existing one (i.e. proto_find_num gives a protocol number when asking to find link between the two). We also annotate protocol description for eth and vlan with the full header size and track the offset from the current base. Otherwise, 'vlan type ip' fetches the protocol field from mac header offset 0, which is some mac address. Instead, we must consider full size of ethernet header. Signed-off-by: Florian Westphal <fw@strlen.de>
* src: use new symbols in libnftnlPablo Neira Ayuso2015-09-162-42/+42
| | | | | | | | | Adapt the nftables code to use the new symbols in libnftnl. This patch contains quite some renaming to reserve the nft_ prefix for our high level library. Explicitly request libnftnl 1.0.5 at configure stage. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* rule: add chain reference counterPablo Neira Ayuso2015-08-181-0/+3
| | | | | | | When adding declared chains to the cache, we may hold more than one single reference from struct cmd and the cache. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* rule: add reference counter to the table objectPablo Neira Ayuso2015-08-181-0/+3
| | | | | | | We may hold multiple references to table objects in follow up patches when adding object declarations to the cache. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: add cache infrastructure and use it for table objectsPablo Neira Ayuso2015-08-181-0/+3
| | | | | | | | | | This patch introduces the generic object cache that is populated during the evaluation phase. The first client of this infrastructure are table objects. As a result, there is a single call to netlink_list_tables(). Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* Merge branch 'next-4.2'Pablo Neira Ayuso2015-08-182-0/+10
|\ | | | | | | | | | | | | | | | | | | This branch adds support for the new 'netdev' family. This also resolves a simple conflict with the default chain policy printing. Conflicts: src/rule.c Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| * src: add netdev family supportPablo Neira Ayuso2015-06-162-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds support for the new 'netdev' table. So far, this table allows you to create filter chains from ingress. The following example shows a very simple base configuration with one table that contains a basechain that is attached to the 'eth0': # nft list table netdev filter table netdev filter { chain eth0-ingress { type filter hook ingress device eth0 priority 0; policy accept; } } You can test that this works by adding a simple rule with counters: # nft add rule netdev filter eth0-ingress counter Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* | src: set chain->hookstr from delinearizationPablo Neira Ayuso2015-07-061-0/+1
|/ | | | | | Set human readable hookname chain->hookstr field from delinearize. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netlink: pad constant concat sub-expressionsPatrick McHardy2015-06-021-0/+10
| | | | | | Pad all but the last sub-expressions of a concat expressions. Signed-off-by: Patrick McHardy <kaber@trash.net>
* netlink_linearize: use NFT_REG32 values internallyPatrick McHardy2015-06-021-0/+5
| | | | | | | | | | | | | | | | | | | Prepare netlink_linearize for 32 bit register usage: Switch to use 16 data registers of 32 bit each. A helper function takes care of mapping the registers to the NFT_REG32 values and, if the register refers to the beginning of an 128 bit area, the old NFT_REG_1-4 values for compatibility. New register reservation and release helper function take the size into account and reserve the required amount of registers. The reservation and release functions will so far still always allocate 128 bit. If no other expression in a rule uses a 32 bit register directly, these will be mapped to the old register values, meaning everything continues to work with old kernel versions. Signed-off-by: Patrick McHardy <kaber@trash.net>
* headers: sync headers for new register valuesPatrick McHardy2015-06-021-1/+33
| | | | Signed-off-by: Patrick McHardy <kaber@trash.net>
* nftables: add set statemetPatrick McHardy2015-04-122-0/+38
| | | | | | | | | | | | The set statement is used to dynamically add or update elements in a set. Syntax: # nft filter input set add tcp dport @myset # nft filter input set add ip saddr timeout 10s @myset # nft filter input set update ip saddr timeout 10s @myset Signed-off-by: Patrick McHardy <kaber@trash.net>
* setelem: add support for attaching comments to set elementsPatrick McHardy2015-04-122-0/+3
| | | | | | | | Syntax: # nft add element filter test { 192.168.0.1 comment "some host" } Signed-off-by: Patrick McHardy <kaber@trash.net>
* setelem: add timeout support for set elementsPatrick McHardy2015-04-122-0/+6
| | | | | | | | | | | | | | | | | | | | | | Support specifying per element timeout values and displaying the expiration time. If an element should not use the default timeout value of the set, an element specific value can be specified as follows: # nft add element filter test { 192.168.0.1, 192.168.0.2 timeout 10m} For listing of elements that use the default timeout value, just the expiration time is shown, otherwise the element specific timeout value is also displayed: set test { type ipv4_addr timeout 1h elements = { 192.168.0.2 timeout 10m expires 9m59s, 192.168.0.1 expires 59m59s} } Signed-off-by: Patrick McHardy <kaber@trash.net>
* set: add timeout support for setsPatrick McHardy2015-04-122-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | Timeout support can be enabled in one of two ways: 1. Using a default timeout value: set test { type ipv4_addr; timeout 1h; } 2. Using the timeout flag without a default: set test { type ipv4_addr; flags timeout; } Optionally a garbage collection interval can be specified using gc-interval <interval>; Signed-off-by: Patrick McHardy <kaber@trash.net>
* expr: add set_elem_expr as container for set element attributesPatrick McHardy2015-04-121-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | Add a new expression type "set_elem_expr" that is used as container for the key in order to attach different attributes, such as timeout values, to the key. The expression hierarchy is as follows: Sets: elem | key Maps: mapping / \ elem data | key Signed-off-by: Patrick McHardy <kaber@trash.net>
* datatype: seperate time parsing/printing from time_typePatrick McHardy2015-04-121-0/+4
| | | | | | | Seperate relative time parsing and printing from the time_type to make it usable for set and set element time related parameters. Signed-off-by: Patrick McHardy <kaber@trash.net>
* src: restore interface to index cachePablo Neira Ayuso2015-04-112-0/+19
| | | | | | | | | | | | | | | | nftables used to have a cache to speed up interface name <-> index lookup, restore it using libmnl. This reduces netlink traffic since if_nametoindex() and if_indextoname() open, send a request, receive the list of interface and close a netlink socket for each call. I think this is also good for consistency since nft -f will operate with the same index number when reloading the ruleset. The cache is populated by when nft_if_nametoindex() and nft_if_indextoname() are used for first time. Then, it it released in the output path. In the interactive mode, it is invalidated after each command. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: introduce netlink_init_error()Pablo Neira Ayuso2015-04-091-1/+3
| | | | | | | | Based on the existing netlink_open_error(), but indicate file and line where the error happens. This will help us to diagnose what is going wrong when users can back to us to report problems. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: allow to specify the default policy for base chainsPablo Neira Ayuso2015-03-171-0/+2
| | | | | | | | | | | | | | | | | | The new syntax is: nft add chain filter input { hook input type filter priority 0\; policy accept\; } but the previous syntax is still allowed: nft add chain filter input { hook input type filter priority 0\; } this assumes default policy to accept. If the base chain already exists, you can update the policy via: nft add chain filter input { policy drop\; } Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: expose table flagsPablo Neira Ayuso2015-03-172-1/+7
| | | | | | | | | | | | | | | | | | | The nf_tables kernel API provides a way to disable a table using the dormant flag. This patch adds the missing code to expose this feature through nft. Basically, if you want to disable a table and all its chains from seen any traffic, you have to type: nft add table filter { flags dormant\; } to re-enable the table, you have to: nft add table filter this clears the flags. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* set: remove unused set_clone() functionPatrick McHardy2015-01-121-1/+0
| | | | | | | | The set_clone() function was added by the event monitor patchset and is unused. It is also broken since it simply initializes the list head to the list of the original set, so remove it. Signed-off-by: Patrick McHardy <kaber@trash.net>
* concat: add concat subtype lookup/id helpersPatrick McHardy2015-01-111-0/+16
| | | | Signed-off-by: Patrick McHardy <kaber@trash.net>
* src: modify pr_debug() to use printf and introduce to pr_gmp_debug()Pablo Neira Ayuso2015-01-081-2/+8
| | | | | | | | | | | | | Modify pr_debug() to use printf so we get debugging traces for proto-ctx when --with-mini-gmp is enabled. Add pr_gmp_debug(), this is disabled with --with-mini-gmp since it relies on the gmp_printf(), which is not available in the mini-gmp implementation. Suggested by Patrick. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* build: add --with-mini-gmp switch to disable linking libgmpSteven Barth2015-01-084-4/+308
| | | | | | | | | | This allows to disable linking the >400 KB big libgmp and replace it with the builtin mini-gmp which only increases size by ~30KB. Enabling this selectively decreases debugging verbosity (pr_debug). Signed-off-by: Steven Barth <cyrus@openwrt.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* evaluate: reject: fix dependency generation from nft -fPablo Neira Ayuso2015-01-061-0/+2
| | | | | | | | | | | | | | | When nft -f is used, ctx->cmd points to the table object, which contains the corresponding chain, set and rule lists. The reject statement evaluator relies on ctx->cmd->rule to add the payload dependencies, which is doesn't point to the rule in that case. This patch adds the rule context to the eval_ctx structure to update the rule list of statements when generating dependencies, as the reject statement needs. Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=993 Reported-by: Ting-Wei Lan <lantw44@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* datatype: change concat_type_alloc() to construct type from idPatrick McHardy2014-12-161-1/+1
| | | | | | | The kernel only stored the id so we need to be able to reconstruct the datatype from the id only. Signed-off-by: Patrick McHardy <kaber@trash.net>
* utils: add fls()Patrick McHardy2014-12-161-0/+37
| | | | Signed-off-by: Patrick McHardy <kaber@trash.net>
* datatype: add define for maximum number of bits and mask of datatype idPatrick McHardy2014-12-161-0/+3
| | | | | | | | | | | | | | | | | The id of concat datatypes is composed of the ids of the individual datatypes. Add a define for the number of bits for each datatype id and a mask. The number of bits is chosen as 6, allowing for 63 datatypes, or twice as much as we currently have. This allows for concatenations of 5 types using 32 bits. The value is statically chosen instead of basing it on the current numbers of datatypes since we don't want the maximum concatenation size to vary between versions, also new versions are supposed to be able to propery parse a ruleset generated by an older version. Signed-off-by: Patrick McHardy <kaber@trash.net>
* datatype: add new subtypes field to account number of concat data typesPatrick McHardy2014-12-161-0/+2
| | | | | | | | Using the size is confusing since it usually holds the size of the data. Add a new "subtypes" member, which holds the number of datatypes the concat type is made of. Signed-off-by: Patrick McHardy <kaber@trash.net>
* src: generate set members using integer_type in the appropriate byteorderPablo Neira Ayuso2014-12-091-2/+14
| | | | | | | | | | | | | | | | Rules with header fields that rely on the generic integer datatype from sets are not matching, eg. nft add rule filter input udp length { 9 } counter This set member is an integer represented in host byte order, which obviously doesn't match the header field (in network byte order). Since the integer datatype has no specific byteorder, we have to rely on the expression byteorder instead when configuring the context, before we evaluate the list of set members. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* build: autotools conversionPablo Neira Ayuso2014-11-123-0/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1) This removes former Makefiles and install-sh (which is now automagically imported via autoreconf). Makefile.defs.in Makefile.in Makefile.rules.in src/Makefile.in install-sh (now automagically imported via autoreconf). 2) CFLAGS are left almost same, they are integrated into Make_global.am. Use AM_CPPFLAGS to set the CFLAGS set by pkgconfig. 3) Add m4 directory to the tree which only contains the .gitignore file. Update .gitignore file to skip autogenerated files. 4) include <config.h> whenever required. 5) Minor adjustments to scanner.l and parser_bison.y to compile cleanly with autotools. 6) Add %option outfile=lex.yy.c to scanner.l, otherwise I hit this error here: gcc -DHAVE_CONFIG_H -I. -I.. -I../include -DDEFAULT_INCLUDE_PATH="\"/usr/etc\"" -Wall -Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations -Wdeclaration-after-statement -Wsign-compare -Winit-self -Wformat-nonliteral -Wformat-security -Wmissing-format-attribute -Wcast-align -Wundef -Wbad-function-cast -g -O2 -MT mnl.o -MD -MP -MF $depbase.Tpo -c -o mnl.o mnl.c &&\ mv -f $depbase.Tpo $depbase.Po /bin/sh ../build-aux/ylwrap scanner.l lex.yy.c scanner.c -- flex make[3]: *** [scanner.c] Error 1 make[3]: Leaving directory `/home/pablo/devel/scm/git-netfilter/nftables/src' make[2]: *** [all] Error 2 make[2]: Leaving directory `/home/pablo/devel/scm/git-netfilter/nftables/src' make[1]: *** [all-recursive] Error 1 make[1]: Leaving directory `/home/pablo/devel/scm/git-netfilter/nftables' make: *** [all] Error 2 7) Add Makefile.am for include/ (contributed by Giorgio Dal Molin). The doc/ and files/ conversion to automake will come in follow up patches but 'make distcheck' already works. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* include: add cli.hPablo Neira Ayuso2014-11-102-12/+20
| | | | | | Needed by follow up patches to use autotools. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: Add cgroup support in meta expresionAna Rey2014-11-101-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | The new attribute of meta is "cgroup". Example of use in nft: # nft add rule ip test output meta cgroup != 0x100001 counter drop Moreover, this adds tests to the meta.t test file. The kernel support is addedin the commit: ce67417 ("netfilter: nft_meta: add cgroup support") The libnftnl support is add in the commit: 1d4a480 ("expr: meta: Add cgroup support") More information about the steps to use cgroup: https://www.kernel.org/doc/Documentation/cgroups/net_cls.txt More info about cgroup in iptables: http://git.kernel.org/cgit/linux/kernel/git/pablo/nftables.git/commit/net/netfilter/xt_cgroup.c?id=82a37132f300ea53bdcd812917af5a6329ec80c3 Signed-off-by: Ana Rey <anarey@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* include: refresh cached copy of nf_tables.hPablo Neira Ayuso2014-11-101-4/+20
| | | | Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* nft: don't resolve hostnames by defaultArturo Borrero2014-11-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | This patch changes the default behaviour of nft to not translate IP addresses to hostnames when printing rules if no options are passed. The options regarding translations after this patch are: <no -n/-N> show IP addresses numerically (default behaviour) -n show IP addresses numerically -nn show Internet services and uid/gid numerically -nnn show protocols numerically -N (--reversedns) translate IP addresses to names The idea is to avoid breaking existing scripts that most likely rely on '-n' to save the ruleset, so we reduce the impact of this patch and provide a default behaviour that doesn't generate network traffic when listing / saving the ruleset. Joint work with Pablo. Suggested-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* utils: indicate file and line on memory allocation errorsPablo Neira Ayuso2014-11-041-1/+4
| | | | | | | | | | | | For example: src/netlink.c:179: Memory allocation failure This shouldn't happen, so this allows us to identify at what point the memory allocation failure has happened. It may be helpful to identify bugs. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: add redirect supportArturo Borrero2014-11-041-0/+10
| | | | | | | | | | | This patch adds redirect support for nft. The syntax is: % nft add rule nat prerouting redirect [port] [nat_flags] Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>