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* scanner: queue: move to own scopeFlorian Westphal2021-03-111-5/+7
| | | | | | allows to remove 3 queue specific keywords from INITIAL scope. Signed-off-by: Florian Westphal <fw@strlen.de>
* scanner: introduce start condition stackFlorian Westphal2021-03-111-7/+29
| | | | | | | | | | | | | | | | | | | | Add a small initial chunk of flex start conditionals. This starts with two low-hanging fruits, numgen and j/symhash. NUMGEN and HASH start conditions are entered from flex when the corresponding expression token is encountered. Flex returns to the INIT condition when the bison parser has seen a complete numgen/hash statement. This intentionally uses a stack rather than BEGIN() to eventually support nested states. The scanner_pop_start_cond() function argument is not used yet, but will need to be used later to deal with nesting. Signed-off-by: Florian Westphal <fw@strlen.de>
* scanner: remove unused tokensFlorian Westphal2021-03-091-6/+0
| | | | Signed-off-by: Florian Westphal <fw@strlen.de>
* tcpopts: clean up parser -> tcpopt.c plumbingFlorian Westphal2020-11-091-1/+2
| | | | | | | | | | | | | | | | | tcpopt template mapping is asymmetric: one mapping is to match dumped netlink exthdr expression to the original tcp option template. This struct is indexed by the raw, on-write kind/type number. The other mapping maps parsed options to the tcp option template. Remove the latter. The parser is changed to translate the textual option name, e.g. "maxseg" to the on-wire number. This avoids the second mapping, it will also allow to more easily support raw option matching in a followup patch. Signed-off-by: Florian Westphal <fw@strlen.de>
* parser: merge sack-perm/sack-permitted and maxseg/mssFlorian Westphal2020-11-091-4/+4
| | | | | | | | | | | | | | | | | | | | | | One was added by the tcp option parsing ocde, the other by synproxy. So we have: synproxy ... sack-perm synproxy ... mss and tcp option maxseg tcp option sack-permitted This kills the extra tokens on the scanner/parser side, so sack-perm and sack-permitted can both be used. Likewise, 'synproxy maxseg' and 'tcp option mss size 42' will work too. On the output side, the shorter form is now preferred, i.e. sack-perm and mss. Signed-off-by: Florian Westphal <fw@strlen.de>
* src/scanner.l: fix whitespace issue for the TRANSPARENT keywordBalazs Scheidler2020-08-291-1/+1
| | | | | Signed-off-by: Balazs Scheidler <bazsi77@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* socket: add support for "wildcard" keyBalazs Scheidler2020-08-291-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | iptables had a "-m socket --transparent" which didn't match sockets that are bound to all addresses (e.g. 0.0.0.0 for ipv4, and ::0 for ipv6). It was possible to override this behavior by using --nowildcard, in which case it did match zero bound sockets as well. The issue is that nftables never included the wildcard check, so in effect it behaved like "iptables -m socket --transparent --nowildcard" with no means to exclude wildcarded listeners. This is a problem as a user-space process that binds to 0.0.0.0:<port> that enables IP_TRANSPARENT would effectively intercept traffic going in _any_ direction on the specific port, whereas in most cases, transparent proxies would only need this for one specific address. The solution is to add "socket wildcard" key to the nft_socket module, which makes it possible to match on the wildcardness of a socket from one's ruleset. This is how to use it: table inet haproxy { chain prerouting { type filter hook prerouting priority -150; policy accept; socket transparent 1 socket wildcard 0 mark set 0x00000001 } } This patch effectively depends on its counterpart in the kernel. Signed-off-by: Balazs Scheidler <bazsi77@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* src: nat concatenation support with anonymous mapsPablo Neira Ayuso2020-02-241-0/+1
| | | | | | | | | This patch extends the parser to define the mapping datatypes, eg. ... dnat ip addr . port to ip saddr map { 1.1.1.1 : 2.2.2.2 . 30 } ... dnat ip addr . port to ip saddr map @y Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: use list_is_first() from scanner_pop_indesc()Pablo Neira Ayuso2020-02-131-1/+1
| | | | | | | | | | !list_empty() always stands true since the list is never empty when calling scanner_pop_indesc(). Check for list_is_first() which actually tells us this is the initial input file, hence, state->indesc is set to NULL. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: remove parser_state->indesc_idxLaurent Fasnacht2020-02-131-6/+0
| | | | | | | | Now that we have a proper stack implementation, we don't need an additional counter for the number of buffer state pushed. Signed-off-by: Laurent Fasnacht <fasnacht@protonmail.ch> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: fix indesc_list stack to be in the correct orderLaurent Fasnacht2020-02-131-1/+5
| | | | | | | This fixes the location displayed in error messages. Signed-off-by: Laurent Fasnacht <fasnacht@protonmail.ch> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* Inclusion depth was computed incorrectly for glob includes.Laurent Fasnacht2020-02-131-6/+14
| | | | | Signed-off-by: Laurent Fasnacht <fasnacht@protonmail.ch> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: remove parser_state->indescs static arrayLaurent Fasnacht2020-02-131-6/+7
| | | | | | | | This static array is redundant with the indesc_list structure, but is less flexible. Signed-off-by: Laurent Fasnacht <fasnacht@protonmail.ch> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: move indesc list append in scanner_push_indescLaurent Fasnacht2020-02-111-9/+7
| | | | | | | Having a single point makes refactoring easier. Signed-off-by: Laurent Fasnacht <fasnacht@protonmail.ch> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: move the file descriptor to be in the input_descriptor structureLaurent Fasnacht2020-02-111-9/+9
| | | | | | | | This prevents a static allocation of file descriptors array, thus allows more flexibility. Signed-off-by: Laurent Fasnacht <fasnacht@protonmail.ch> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: Extend asteriskstring definitionPhil Sutter2020-02-101-1/+1
| | | | | | | | Accept escaped asterisks also mid-string and as only character. Especially the latter will help when translating from iptables where asterisk has no special meaning. Signed-off-by: Phil Sutter <phil@nwl.cc>
* scanner: incorrect error reporting after file inclusionPablo Neira Ayuso2020-01-051-3/+19
| | | | | | | | | | | scanner_pop_buffer() incorrectly sets the current input descriptor. The state->indesc_idx field actually stores the number of input descriptors in the stack, decrement it and then update the current input descriptor accordingly. Fixes: 60e917fa7cb5 ("src: dynamic input_descriptor allocation") Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1383 Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* parser: add typeof keyword for declarationsPablo Neira Ayuso2019-12-171-0/+1
| | | | | | | | | | | | | | | | | | Add a typeof keyword to automatically use the correct type in set and map declarations. table filter { set blacklist { typeof ip saddr } chain input { ip saddr @blacklist counter drop } } Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Florian Westphal <fw@strlen.de>
* scanner: fix out-of-bound memory write in include_file()Eric Jallot2019-12-021-12/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before patch: # echo 'include "/tmp/rules.nft"' > /tmp/rules.nft # nft -f /tmp/rules.nft In file included from /tmp/rules.nft:1:1-25: from /tmp/rules.nft:1:1-25: [snip] from /tmp/rules.nft:1:1-25: /tmp/rules.nft:1:1-25: Error: Include nested too deeply, max 16 levels include "/tmp/rules.nft" ^^^^^^^^^^^^^^^^^^^^^^^^^ double free or corruption (out) Aborted (core dumped) valgrind reports: ==8856== Invalid write of size 8 ==8856== at 0x4E8FCAF: include_file (scanner.l:718) ==8856== by 0x4E8FEF6: include_glob (scanner.l:793) ==8856== by 0x4E9985D: scanner_include_file (scanner.l:875) ==8856== by 0x4E89D7A: nft_parse (parser_bison.y:828) ==8856== by 0x4E765E1: nft_parse_bison_filename (libnftables.c:394) ==8856== by 0x4E765E1: nft_run_cmd_from_filename (libnftables.c:497) ==8856== by 0x40172D: main (main.c:340) So perform bounds checking on MAX_INCLUDE_DEPTH before writing. After patch: # nft -f /tmp/rules.nft In file included from /tmp/rules.nft:1:1-25: from /tmp/rules.nft:1:1-25: [snip] from /tmp/rules.nft:1:1-25: /tmp/rules.nft:1:1-25: Error: Include nested too deeply, max 16 levels include "/tmp/rules.nft" ^^^^^^^^^^^^^^^^^^^^^^^^^ # echo $? 1 Also: Update scanner_push_file() function definition accordingly. Fixes: 32325e3c3fab4 ("libnftables: Store top_scope in struct nft_ctx") Signed-off-by: Eric Jallot <ejallot@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* scanner: Introduce numberstringPhil Sutter2019-11-191-11/+2
| | | | | | | | | This token combines decstring and hexstring. The latter two had identical action blocks (which were not completely trivial), this allows to merge them. Signed-off-by: Phil Sutter <phil@nwl.cc> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
* 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>