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* src: add synproxy stateful object supportFernando Fernandez Mancera2019-09-131-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Add support for "synproxy" stateful object. For example (for TCP port 80 and using maps with saddr): table ip foo { synproxy https-synproxy { mss 1460 wscale 7 timestamp sack-perm } synproxy other-synproxy { mss 1460 wscale 5 } chain bar { tcp dport 80 synproxy name "https-synproxy" synproxy name ip saddr map { 192.168.1.0/24 : "https-synproxy", 192.168.2.0/24 : "other-synproxy" } } } Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* meta: Introduce new conditions 'time', 'day' and 'hour'Ander Juaristi2019-09-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These keywords introduce new checks for a timestamp, an absolute date (which is converted to a timestamp), an hour in the day (which is converted to the number of seconds since midnight) and a day of week. When converting an ISO date (eg. 2019-06-06 17:00) to a timestamp, we need to substract it the GMT difference in seconds, that is, the value of the 'tm_gmtoff' field in the tm structure. This is because the kernel doesn't know about time zones. And hence the kernel manages different timestamps than those that are advertised in userspace when running, for instance, date +%s. The same conversion needs to be done when converting hours (e.g 17:00) to seconds since midnight as well. The result needs to be computed modulo 86400 in case GMT offset (difference in seconds from UTC) is negative. We also introduce a new command line option (-t, --seconds) to show the actual timestamps when printing the values, rather than the ISO dates, or the hour. Some usage examples: time < "2019-06-06 17:00" drop; time < "2019-06-06 17:20:20" drop; time < 12341234 drop; day "Saturday" drop; day 6 drop; hour >= 17:00 drop; hour >= "17:00:01" drop; hour >= 63000 drop; We need to convert an ISO date to a timestamp without taking into account the time zone offset, since comparison will be done in kernel space and there is no time zone information there. Overwriting TZ is portable, but will cause problems when parsing a ruleset that has 'time' and 'hour' rules. Parsing an 'hour' type must not do time zone conversion, but that will be automatically done if TZ has been overwritten to UTC. Hence, we use timegm() to parse the 'time' type, even though it's not portable. Overwriting TZ seems to be a much worse solution. Finally, be aware that timestamps are converted to nanoseconds when transferring to the kernel (as comparison is done with nanosecond precision), and back to seconds when retrieving them for printing. We swap left and right values in a range to properly handle cross-day hour ranges (e.g. 23:15-03:22). Signed-off-by: Ander Juaristi <a@juaristi.eus> Reviewed-by: Florian Westphal <fw@strlen.de>
* scanner: don't rely on fseek for input stream repositioningFlorian Westphal2019-07-301-15/+20
| | | | | | | | | | It doesn't work when reading from a pipe, leading to parser errors in case of 'cat foo | nft -f -', whereas 'nft -f < foo' works fine. Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1354 Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: introduce SYNPROXY matchingFernando Fernandez Mancera2019-07-171-0/+5
| | | | | | | | | | | | | | | | | | | | Add support for "synproxy" statement. For example (for TCP port 8888): table ip x { chain y { type filter hook prerouting priority raw; policy accept; tcp dport 8888 tcp flags syn notrack } chain z { type filter hook input priority filter; policy accept; tcp dport 8888 ct state invalid,untracked synproxy mss 1460 wscale 7 timestamp sack-perm ct state invalid drop } } Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: add ct expectations supportStéphane Veyret2019-07-161-0/+1
| | | | | | | This modification allow to directly add/list/delete expectations. Signed-off-by: Stéphane Veyret <sveyret@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* exthdr: add support for matching IPv4 optionsStephen Suryaputra2019-07-041-0/+8
| | | | | | | | | Add capability to have rules matching IPv4 options. This is developed mainly to support dropping of IP packets with loose and/or strict source route route options. Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: enable set expiration date for set elementsLaura Garcia Liebana2019-06-281-0/+1
| | | | | | | | | | | | | | | | Currently, the expiration of every element in a set or map is a read-only parameter generated at kernel side. This change will permit to set a certain expiration date per element that will be required, for example, during stateful replication among several nodes. This patch will enable the _expires_ input parameter in the parser and propagate NFTNL_SET_ELEM_EXPIRATION in order to send the configured value. Signed-off-by: Laura Garcia Liebana <nevola@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: dynamic input_descriptor allocationPablo Neira Ayuso2019-06-051-21/+42
| | | | | | | | | | | | | This patch introduces the input descriptor list, that stores the existing input descriptor objects. These objects are now dynamically allocated and release from scanner_destroy() path. Follow up patches that decouple the parsing and the evaluation phases require this for error reporting as described by b14572f72aac ("erec: Fix input descriptors for included files"), this patch partially reverts such partial. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: file descriptor leak in include_file()Pablo Neira Ayuso2019-03-151-19/+23
| | | | | | | | File that contains the ruleset is never closed, track open files through the nft_ctx object and close them accordingly. Reported-by: Václav Zindulka <vaclav.zindulka@tlapnet.cz> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: add igmp supportPablo Neira Ayuso2019-01-091-0/+3
| | | | Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: add support for setting secmarkChristian Göttsche2018-10-151-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | Add support for new nft object secmark holding security context strings. The following should demonstrate its usage (based on SELinux context): # define a tag containing a context string nft add secmark inet filter sshtag \"system_u:object_r:ssh_server_packet_t:s0\" nft list secmarks # set the secmark nft add rule inet filter input tcp dport 22 meta secmark set sshtag # map usage nft add map inet filter secmapping { type inet_service : secmark \; } nft add element inet filter secmapping { 22 : sshtag } nft list maps nft list map inet filter secmapping nft add rule inet filter input meta secmark set tcp dport map @secmapping [ Original patch based on v0.9.0. Rebase on top on git HEAD. --pablo ] Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: add ipsec (xfrm) expressionMáté Eckl2018-09-211-0/+9
| | | | | | | | | | | | | | | | This allows matching on ipsec tunnel/beet addresses in xfrm state associated with a packet, ipsec request id and the SPI. Examples: ipsec in ip saddr 192.168.1.0/24 ipsec out ip6 daddr @endpoints ipsec in spi 1-65536 Joint work with Florian Westphal. Cc: Máté Eckl <ecklm94@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de>
* src: rt: add support to check if route will perform ipsec transformationFlorian Westphal2018-09-211-0/+1
| | | | | Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: Set/print standard chain prios with textual namesMáté Eckl2018-08-141-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the possibility to use textual names to set the chain priority to standard values so that numeric values do not need to be learnt any more for basic usage. Basic arithmetic can also be done with them to ease the addition of relatively higher/lower priority chains. Addition and substraction is possible. Values are also printed with their friendly name within the range of <basicprio> +- 10. Also numeric printing is supported in case of -nnn option (numeric == NFT_NUMERIC_ALL) The supported name-value pairs and where they are valid is based on how x_tables use these values when registering their base chains. (See iptables/nft.c in the iptables repository). Also see the compatibility matrices extracted from the man page: Standard priority names, family and hook compatibility matrix ┌─────────┬───────┬────────────────┬─────────────┐ │Name │ Value │ Families │ Hooks │ ├─────────┼───────┼────────────────┼─────────────┤ │ │ │ │ │ │raw │ -300 │ ip, ip6, inet │ all │ ├─────────┼───────┼────────────────┼─────────────┤ │ │ │ │ │ │mangle │ -150 │ ip, ip6, inet │ all │ ├─────────┼───────┼────────────────┼─────────────┤ │ │ │ │ │ │dstnat │ -100 │ ip, ip6, inet │ prerouting │ ├─────────┼───────┼────────────────┼─────────────┤ │ │ │ │ │ │filter │ 0 │ ip, ip6, inet, │ all │ │ │ │ arp, netdev │ │ ├─────────┼───────┼────────────────┼─────────────┤ │ │ │ │ │ │security │ 50 │ ip, ip6, inet │ all │ ├─────────┼───────┼────────────────┼─────────────┤ │ │ │ │ │ │srcnat │ 100 │ ip, ip6, inet │ postrouting │ └─────────┴───────┴────────────────┴─────────────┘ Standard priority names and hook compatibility for the bridge family ┌───────┬───────┬─────────────┐ │ │ │ │ │Name │ Value │ Hooks │ ├───────┼───────┼─────────────┤ │ │ │ │ │dstnat │ -300 │ prerouting │ ├───────┼───────┼─────────────┤ │ │ │ │ │filter │ -200 │ all │ ├───────┼───────┼─────────────┤ │ │ │ │ │out │ 100 │ output │ ├───────┼───────┼─────────────┤ │ │ │ │ │srcnat │ 300 │ postrouting │ └───────┴───────┴─────────────┘ This can be also applied for flowtables wher it works as a netdev family chain. Example: nft> add table ip x nft> add chain ip x y { type filter hook prerouting priority raw; } nft> add chain ip x z { type filter hook prerouting priority mangle + 1; } nft> add chain ip x w { type filter hook prerouting priority dstnat - 5; } nft> add chain ip x r { type filter hook prerouting priority filter + 10; } nft> add chain ip x t { type filter hook prerouting priority security; } nft> add chain ip x q { type filter hook postrouting priority srcnat + 11; } nft> add chain ip x h { type filter hook prerouting priority 15; } nft> nft> add flowtable ip x y { hook ingress priority filter + 5 ; devices = {enp0s31f6}; } nft> nft> add table arp x nft> add chain arp x y { type filter hook input priority filter + 5; } nft> nft> add table bridge x nft> add chain bridge x y { type filter hook input priority filter + 9; } nft> add chain bridge x z { type filter hook prerouting priority dstnat; } nft> add chain bridge x q { type filter hook postrouting priority srcnat; } nft> add chain bridge x k { type filter hook output priority out; } nft> nft> list ruleset table ip x { flowtable y { hook ingress priority filter + 5 devices = { enp0s31f6 } } chain y { type filter hook prerouting priority raw; policy accept; } chain z { type filter hook prerouting priority mangle + 1; policy accept; } chain w { type filter hook prerouting priority dstnat - 5; policy accept; } chain r { type filter hook prerouting priority filter + 10; policy accept; } chain t { type filter hook prerouting priority security; policy accept; } chain q { type filter hook postrouting priority 111; policy accept; } chain h { type filter hook prerouting priority 15; policy accept; } } table arp x { chain y { type filter hook input priority filter + 5; policy accept; } } table bridge x { chain y { type filter hook input priority filter + 9; policy accept; } chain z { type filter hook prerouting priority dstnat; policy accept; } chain q { type filter hook postrouting priority srcnat; policy accept; } chain k { type filter hook output priority out; policy accept; } } nft> # Everything should fail after this nft> add chain ip x h { type filter hook prerouting priority first; } Error: 'first' is invalid priority in this context. add chain ip x h { type filter hook prerouting priority first; } ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ nft> add chain ip x q { type filter hook prerouting priority srcnat + 11; } Error: 'srcnat' is invalid priority in this context. add chain ip x q { type filter hook prerouting priority srcnat + 11; } ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ nft> add chain arp x y { type filter hook input priority raw; } Error: 'raw' is invalid priority in this context. add chain arp x y { type filter hook input priority raw; } ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ nft> add flowtable ip x y { hook ingress priority magle; devices = {enp0s31f6}; } Error: 'magle' is invalid priority. add flowtable ip x y { hook ingress priority magle; devices = {enp0s31f6}; } ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ nft> add chain bridge x r { type filter hook postrouting priority dstnat; } Error: 'dstnat' is invalid priority in this context. add chain bridge x r { type filter hook postrouting priority dstnat; } ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ nft> add chain bridge x t { type filter hook prerouting priority srcnat; } Error: 'srcnat' is invalid priority in this context. add chain bridge x t { type filter hook prerouting priority srcnat; } ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Signed-off-by: Máté Eckl <ecklm94@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: introduce passive OS fingerprint matchingFernando Fernandez Mancera2018-08-041-0/+2
| | | | | | | | | | | | | | Add support for "osf" expression. Example: table ip foo { chain bar { type filter hook input priority 0; policy accept; osf name "Linux" counter packets 3 bytes 132 } } Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: Add tproxy supportMáté Eckl2018-08-031-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds support for transparent proxy functionality which is supported in ip, ip6 and inet tables. The syntax is the following: tproxy [{|ip|ip6}] to {<ip address>|:<port>|<ip address>:<port>} It looks for a socket listening on the specified address or port and assigns it to the matching packet. In an inet table, a packet matches for both families until address is specified. Network protocol family has to be specified **only** in inet tables if address is specified. As transparent proxy support is implemented for sockets with layer 4 information, a transport protocol header criterion has to be set in the same rule. eg. 'meta l4proto tcp' or 'udp dport 4444' Example ruleset: table ip x { chain y { type filter hook prerouting priority -150; policy accept; tcp dport ntp tproxy to 1.1.1.1 udp dport ssh tproxy to :2222 } } table ip6 x { chain y { type filter hook prerouting priority -150; policy accept; tcp dport ntp tproxy to [dead::beef] udp dport ssh tproxy to :2222 } } table inet x { chain y { type filter hook prerouting priority -150; policy accept; tcp dport 321 tproxy to :ssh tcp dport 99 tproxy ip to 1.1.1.1:999 udp dport 155 tproxy ip6 to [dead::beef]:smux } } Signed-off-by: Máté Eckl <ecklm94@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: Do not convert tabs into spacesPhil Sutter2018-06-181-15/+1
| | | | | | | | | | | | | | | | | | | | | Commit 2f86dd5a43baf ("erec: Review erec_print()") changed erec_print() function to expect tabs in input by replacing the whitespace character in the marker line at the same offset with a tab character so that the marker aligns with the offending part of input. The need for that came from JSON input not having its tabs converted to spaces, which erec_print() didn't expect. Above change though has a shortcoming: When reading standard syntax input from a file, Flex code converts tabs into spaces. Location information is taken from this converted input, but when printing an error message, the offending input line is read from the input file directly (which still contains tabs). The solution is to simply drop said tab conversion from scanner.l. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: add dynamic flag and use itPablo Neira Ayuso2018-06-121-0/+1
| | | | | | | We need to signal the kernel to use a set backend that supports dynamic updates. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: Introduce socket matchingMáté Eckl2018-06-061-0/+3
| | | | | | | | | | | | | | | | For now it can only match sockets with IP(V6)_TRANSPARENT socket option set. Example: table inet sockin { chain sockchain { type filter hook prerouting priority -150; policy accept; socket transparent 1 mark set 0x00000001 nftrace set 1 counter packets 9 bytes 504 accept } } Signed-off-by: Máté Eckl <ecklm94@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* Support 'add/insert rule index <IDX>'Phil Sutter2018-05-091-0/+1
| | | | | | | | | | | Allow to specify an absolute rule position in add/insert commands like with iptables. The translation to rule handle takes place in userspace, so no kernel support for this is needed. Possible undesired effects are pointed out in man page to make users aware that this way of specifying a rule location might not be ideal. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: support timeouts in millisecondsFlorian Westphal2018-05-091-1/+1
| | | | | | | | | | currently the frontend uses seconds everywhere and multiplies/divides by 1000. Pass milliseconds around instead and extend the scanner to accept 'ms' in timestrings. Signed-off-by: Florian Westphal <fw@strlen.de>
* scanner: Support rfc4291 IPv4-compatible addressesPhil Sutter2018-05-061-1/+2
| | | | | | | | | | | These are defined in section 2.5.5.1. Although it is stated that they are deprecated and new implementations are not required to support them, they occur in ruleset output if an address in the form '::feed:babe' was given in input. In order to support reinsertion of that rule, we have to support those deprecated addresses as well. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: use ibrname and obrnamePablo Neira Ayuso2018-04-191-2/+2
| | | | | | | | | Legacy tool name is 'brctl' and so the 'br' prefix is already known. If we use ibrname and obrname it looks consistent with iifname and oifname. So let's this instead of ibridgename and obridgename since Florian likes this too. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: rename ibrportname, obrportnameFlorian Westphal2018-04-171-0/+2
| | | | | | | | | | | | | | | For bridge, iifname is the port name, whereas 'ibrport' is the logical name of the bridge ("br0") the port ("iifname") is enslaved to. So, 'ibrport' is a misnomer. libnftl calls these 'bri_iifname' and 'bri_oifname', which is good but using 'briiifname' in nft is rather ugly, so use 'ibridgename' and 'obridgename' instead. Old names are still recognized, listing shows the new names. Signed-off-by: Florian Westphal <fw@strlen.de>
* scanner: add helpers tokenFlorian Westphal2018-04-171-0/+1
| | | | | | | | | without it, you get: nft list ct helpers table filter Error: syntax error, unexpected string, expecting helper or helpers Fixes: 14fd3ad720f6e ("src: prepare for future ct timeout policy support") Signed-off-by: Florian Westphal <fw@strlen.de>
* erec: Review erec_print()Phil Sutter2018-04-141-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A new requirement to erec for the upcoming JSON support is printing records with file input descriptors without open stream. The approach is to treat 'name' field as file name, open it, extract the offending line and close it again. Further changes to libnftables input parsing routines though have shown that the whole concept of file pointer reuse in erec is tedious and not worth keeping: * Closed files are to be supported as well, so there needs to be fallback code for opening the file anyway. * When input descriptor is duplicated from parser state into an error record, the file pointer is copied as well. Therefore care has to be taken to not free the parser state before any error records have been printed. This is the only point where old and duplicated input descriptors are connected. Therefore drop struct input_descriptor's 'fp' field and just always open the file by name. This way also the old stream offset doesn't have to be restored after reading. While being at it, this patch fixes two other (potential) problems: * If the offending line from input contains tabs, add them at the right position in the marker buffer as well to avoid misalignment. * The input file may not be seekable (/dev/stdin for instance), so skip printing of offending line and markers if it couldn't be read properly. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* libnftables: Fix for input without trailing newlinePhil Sutter2018-04-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Input parser implementation requires a newline at end of input, otherwise the last pattern may not be recognized correctly. If input comes from a file, the culprit was YY_INPUT macro not expecting the last line not ending with a newline, so the last word wasn't accepted. This is easily fixed by checking for feof(yyin) in there. A simple test case for that is: | echo -en "table ip t {\nchain c {\n}\n}" >/tmp/foo | nft -f /tmp/foo Input from a string buffer is a bit more tricky: The culprit here is that detection of classid pattern is done by checking the character following it which makes it impossible to sit right at end of input and I haven't found an alternative to that. After dropping the manual newline appending when combining argv into a single buffer in main(), a rule like this won't be recognized anymore: | nft add rule ip t c meta priority feed:babe Since a direct call to run_cmd_from_buffer() via libnftables bypasses the sanitizing done in main() entirely, it has to happen in libnftables instead which means creating a newline-terminated duplicate of the input buffer. Note that main() created a buffer one byte longer than needed since it accounts for whitespace at end of each argv but doesn't add it to the buffer for the last one, so buffer length is reduced by two bytes instead of just one although only one less character is printed into it. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: Adding support for segment routing header 'srh'Ahmed Abdelsalam2018-03-111-0/+4
| | | | | | | | | | | | | | Segment Routing Header "SRH" is new type of IPv6 Routing extension header (type 4). SRH contains a list of segments (each is represented as an IPv6 address) to be visited by packets during the journey from source to destination. The SRH specification are defined in the below IETF SRH draft. https://tools.ietf.org/html/draft-ietf-6man-segment-routing-header-07 Signed-off-by: Ahmed Abdelsalam <amsalam20@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: support for get element commandPablo Neira Ayuso2018-03-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | You need a Linux kernel >= 4.15 to use this feature. This patch allows us to dump the content of an existing set. # nft list ruleset table ip x { set x { type ipv4_addr flags interval elements = { 1.1.1.1-2.2.2.2, 3.3.3.3, 5.5.5.5-6.6.6.6 } } } You check if a single element exists in the set: # nft get element x x { 1.1.1.5 } table ip x { set x { type ipv4_addr flags interval elements = { 1.1.1.1-2.2.2.2 } } } Output means '1.1.1.5' belongs to the '1.1.1.1-2.2.2.2' interval. You can also check for intervals: # nft get element x x { 1.1.1.1-2.2.2.2 } table ip x { set x { type ipv4_addr flags interval elements = { 1.1.1.1-2.2.2.2 } } } If you try to check for an element that doesn't exist, an error is displayed. # nft get element x x { 1.1.1.0 } Error: Could not receive set elements: No such file or directory get element x x { 1.1.1.0 } ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ You can also check for multiple elements in one go: # nft get element x x { 1.1.1.5, 5.5.5.10 } table ip x { set x { type ipv4_addr flags interval elements = { 1.1.1.1-2.2.2.2, 5.5.5.5-6.6.6.6 } } } You can also use this to fetch the existing timeout for specific elements, in case you have a set with timeouts in place: # nft get element w z { 2.2.2.2 } table ip w { set z { type ipv4_addr timeout 30s elements = { 2.2.2.2 expires 17s } } } Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: flow offload supportPablo Neira Ayuso2018-03-051-0/+1
| | | | | | | | | | | | This patch allows us to refer to existing flowtables: # nft add rule x x flow offload @m Packets matching this rule create an entry in the flow table 'm', hence, follow up packets that get to the flowtable at ingress bypass the classic forwarding path. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: add support to add flowtablesPablo Neira Ayuso2018-03-051-0/+2
| | | | | | | | | | | | | | | | | This patch allows you to create flowtable: # nft add table x # nft add flowtable x m { hook ingress priority 10\; devices = { eth0, wlan0 }\; } You have to specify hook and priority. So far, only the ingress hook is supported. The priority represents where this flowtable is placed in the ingress hook, which is registered to the devices that the user specifies. You can also use the 'create' command instead to bail out in case that there is an existing flowtable with this name. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: support for flowtable listingPablo Neira Ayuso2018-03-051-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | This patch allows you to dump existing flowtable. # nft list ruleset table ip x { flowtable x { hook ingress priority 10 devices = { eth0, tap0 } } } You can also list existing flowtables via: # nft list flowtables table ip x { flowtable x { hook ingress priority 10 devices = { eth0, tap0 } } } You need a Linux kernel >= 4.16-rc to test this new feature. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* Added undefine/redefine keywordsDavid Fabian2018-02-261-0/+2
| | | | | | | | | | | | | | | | | This is a small patch to nft which adds two new keywords - undefine and redefine. undefine simply undefines a variable from the current scope. redefine allows one to change a variable definition. We have a firewall written in bash (using iptables) that is organized by customer VLANs. Each VLAN has its own set of bash variables holding things like uplink iface names, gateway IPs, etc. We want to rewrite the firewall to nftables but are stuck on the fact that nft variables cannot be overridden in the same scope. We have each VLAN configuration in a separate file containing pre/post-routing, input, output and forward rules,and we include those files to a master firewall configuration. One solution is to rename all the variables with some VLAN specific (pre/su)ffix. But that is cumbersome. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: add 'auto-merge' option to setsPablo Neira Ayuso2018-01-221-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After discussions with Karel here: https://bugzilla.netfilter.org/show_bug.cgi?id=1184 And later on with Phil Sutter, we decided to disable the automatic merge feature in sets with intervals. This feature is problematic because it introduces an inconsistency between what we add and what we later on get. This is going to get worse with the upcoming timeout support for intervals. Therefore, we turned off this by default. However, Jeff Kletsky and folks like this feature, so let's restore this behaviour on demand with this new 'auto-merge' statement, that you can place on the set definition, eg. # nft list ruleset table ip x { ... set y { type ipv4_addr flags interval auto-merge } } # nft add element x z { 1.1.1.1-2.2.2.2, 1.1.1.2 } Regarding implementation details: Given this feature only makes sense from userspace, let's store this in the set user data area, so nft knows it has to do automatic merge of adjacent/overlapping elements as per user request. # nft add set x z { type ipv4_addr\; auto-merge\; } Error: auto-merge only works with interval sets add set x z { type ipv4_addr; auto-merge; } ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Fixes: https://bugzilla.netfilter.org/show_bug.cgi?id=1216 Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: Add import command for low level jsonShyam Saini2018-01-171-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This new operation allows to import low level virtual machine ruleset in json to make incremental changes using the parse functions of libnftnl. A basic way to test this new functionality is: $ cat file.json | nft import vm json where the file.json is a ruleset exported in low level json format. To export json rules in low level virtual machine format we need to specify "vm" token before json. See below $ nft export vm json and $ nft export/import json will do no operations. Same goes with "$nft monitor" Highly based on work from Alvaro Neira <alvaroneay@gmail.com> and Arturo Borrero <arturo@netfilter.org> Acked-by: Arturo Borrero Gonzalez <arturo@netfilter.org> Signed-off-by: Shyam Saini <mayhs11saini@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: deprecate "flow table" syntax, replace it by "meter"Pablo Neira Ayuso2017-11-241-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | According to bugzilla 1137: "flow tables" should not be syntactically unique. "Flow tables are always named, but they don't conform to the way sets, maps, and dictionaries work in terms of "add" and "delete" and all that. They are also "flow tables" instead of one word like "flows" or "throttle" or something. It seems weird to just have these break the syntactic expectations." Personally, I never liked the reference to "table" since we have very specific semantics in terms of what a "table" is netfilter for long time. This patch promotes "meter" as the new keyword. The former syntax is still accepted for a while, just to reduce chances of breaking things. At some point the former syntax will just be removed. Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1137 Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Arturo Borrero Gonzalez <arturo@netfilter.org>
* libnftables: Introduce getters and setters for everythingPhil Sutter2017-10-241-3/+1
| | | | | | | | | | | | | | | | | | | | | | | | | This introduces getter/setter pairs for all parts in struct nft_ctx (and contained structs) which should be configurable. Most of them are simple ones, just allowing to get/set a given field: * nft_ctx_{get,set}_dry_run() -> ctx->check * nft_ctx_output_{get,set}_numeric() -> ctx->output.numeric * nft_ctx_output_{get,set}_stateless() -> ctx->output.stateless * nft_ctx_output_{get,set}_ip2name() -> ctx->output.ip2name * nft_ctx_output_{get,set}_debug() -> ctx->debug_mask * nft_ctx_output_{get,set}_handle() -> ctx->output.handle * nft_ctx_output_{get,set}_echo() -> ctx->output.echo A more complicated case is include paths handling: In order to keep the API simple, remove INCLUDE_PATHS_MAX restraint and dynamically allocate nft_ctx field include_paths instead. So there is: * nft_ctx_add_include_path() -> add an include path to the list * nft_ctx_clear_include_paths() -> flush the list of include paths Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: IPv4-Mapped IPv6 addresses supportPablo Neira Ayuso2017-10-091-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The scanner rejects IPv4-Mapped IPv6 addresses, eg. # cat test #!/usr/sbin/nft -f flush ruleset table inet global { set blackhole_ipv6 { type ipv6_addr flags interval elements = { ::ffff:0.0.0.0/96 } } } # nft -f test test:8:30-38: Error: syntax error, unexpected string, expecting comma or '}' elements = { ::ffff:0.0.0.0/96 } ^^^^^^^^^^ According to RFC4291, Sect. 2.5.5.2. IPv4-Mapped IPv6 Address: | 80 bits | 16 | 32 bits | +--------------------------------------+--------------------------+ |0000..............................0000|FFFF| IPv4 address | +--------------------------------------+----+---------------------+ Update scanner bits to parse this. Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1188 Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* parser_bison: use keywords in ct expressionPablo Neira Ayuso2017-09-271-0/+9
| | | | | | | | Using string give us more chances to hit shift/reduce conflicts when extending this grammar, more specifically, from the stmt_expr rule, so add keywords for this. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: add stateful object support for limitPablo M. Bermudo Garay2017-09-041-0/+1
| | | | | | | | This patch adds support for a new type of stateful object: limit. Creation, deletion and listing operations are supported. Signed-off-by: Pablo M. Bermudo Garay <pablombg@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: Make use of yylex_init_extra()Phil Sutter2017-08-241-2/+1
| | | | | | This combines the calls to yylex_init() and yyset_extra(). Signed-off-by: Phil Sutter <phil@nwl.cc>
* scanner: Fix for wrong parameter type of scanner_destroy()Phil Sutter2017-08-241-1/+1
| | | | | | | | The function takes the scanner as argument, not the state. This wasn't a real issue since scanner is a void pointer, which means it's only casted around without need. So this fix is a rather cosmetic one. Signed-off-by: Phil Sutter <phil@nwl.cc>
* scanner: Fix for memleak due to unclosed file pointerPhil Sutter2017-08-241-1/+2
| | | | | | | | | | | | | | | | | | | | When including a file, it is opened by fopen() and therefore needs to be closed after scanning has finished using fclose(), otherwise valgrind will report a memleak. This patch changes struct input_descriptor to track the opened FILE pointer instead of the file descriptor so the pointer is available for closing in scanner_destroy(). While at it, change erec_print() to work on the open FILE pointer so it doesn't have to call fileno() in beforehand. And as a little bonus, use C99 initializer of the buffer to get rid of the call to memset(). Note that it is necessary to call erec_print_list() prior to destroying the scanner, otherwise it will start manipulating an already freed FILE pointer (and therefore crash the program). Signed-off-by: Phil Sutter <phil@nwl.cc>
* src: add include_paths to struct nft_ctxPablo Neira Ayuso2017-08-231-5/+5
| | | | | | | Not convenient to keep this as static for the upcoming library, so let's move it where it belongs. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: handle rule tracing as an monitor objectPablo Neira Ayuso2017-08-021-0/+1
| | | | | | Traces are not an event type, they should be handled as an object. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: free filename when destroying scannerEric Leblond2017-07-171-2/+9
| | | | | | | | To be able to do so we duplicate the name in the indesc if it is set. Signed-off-by: Eric Leblond <eric@regit.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: support for wildcards in include statements.Ismo Puustinen2017-06-271-119/+107
| | | | | | | | | | | | | | | | Use glob() to find paths in include statements. The rules are these: 1. If no files can be found in the pattern with wildcards, do not return an error. 2. Do not match any files beginning with '.'. 3. Do not handle include directories anymore. For example, the statement: include "foo/" would now need to be rewritten: include "foo/*" Signed-off-by: Ismo Puustinen <ismo.puustinen@intel.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: add files in include dirs in alphabetical order.Ismo Puustinen2017-06-071-27/+70
| | | | | | | | | | | | | | | | | | This means that if you have a directory structure like this /foo /foo/02_rules.nft /foo/01_rules.nft where *.nft files in directory /foo are nft scripts, then an include statement in another nft script like this include "/foo/" guarantees that "01_rules.nft" is loaded before "02_rules.nft". Signed-off-by: Ismo Puustinen <ismo.puustinen@intel.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: add support for include directoriesIsmo Puustinen2017-06-061-23/+109
| | | | | | | | | | | | | | | | If a string after "include" keyword points to a directory instead of a file, consider the directory to contain only nft rule files and try to load them all. This helps with a use case where services drop their own firewall configuration files into a directory and nft needs to include those without knowing the exact file names. File loading order from the include directory is not specified, so the files inside an include directory should not depend on each other. Fixes(Bug 1154 - Allow include statement to operate on directories and/or wildcards). Signed-off-by: Ismo Puustinen <ismo.puustinen@intel.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* exthdr: Implement existence checkPhil Sutter2017-03-101-0/+2
| | | | | | | | | | | This allows to check for existence of an IPv6 extension or TCP option header by using the following syntax: | exthdr frag exists | tcpopt window exists Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>