linux/include/net/netfilter, branch v5.6

nf_tables: Add set type for arbitrary concatenation of ranges

2020-01-27T07:54:30Z

This new set type allows for intervals in concatenated fields, which are expressed in the usual way, that is, simple byte concatenation with padding to 32 bits for single fields, and given as ranges by specifying start and end elements containing, each, the full concatenation of start and end values for the single fields. Ranges are expanded to composing netmasks, for each field: these are inserted as rules in per-field lookup tables. Bits to be classified are divided in 4-bit groups, and for each group, the lookup table contains 4^2 buckets, representing all the possible values of a bit group. This approach was inspired by the Grouper algorithm: http://www.cse.usf.edu/~ligatti/projects/grouper/ Matching is performed by a sequence of AND operations between bucket values, with buckets selected according to the value of packet bits, for each group. The result of this sequence tells us which rules matched for a given field. In order to concatenate several ranged fields, per-field rules are mapped using mapping arrays, one per field, that specify which rules should be considered while matching the next field. The mapping array for the last field contains a reference to the element originally inserted. The notes in nft_set_pipapo.c cover the algorithm in deeper detail. A pure hash-based approach is of no use here, as ranges need to be classified. An implementation based on "proxying" the existing red-black tree set type, creating a tree for each field, was considered, but deemed impractical due to the fact that elements would need to be shared between trees, at least as long as we want to keep UAPI changes to a minimum. A stand-alone implementation of this algorithm is available at: https://pipapo.lameexcu.se together with notes about possible future optimisations (in pipapo.c). This algorithm was designed with data locality in mind, and can be highly optimised for SIMD instruction sets, as the bulk of the matching work is done with repetitive, simple bitwise operations. At this point, without further optimisations, nft_concat_range.sh reports, for one AMD Epyc 7351 thread (2.9GHz, 512 KiB L1D$, 8 MiB L2$): TEST: performance net,port [ OK ] baseline (drop from netdev hook): 10190076pps baseline hash (non-ranged entries): 6179564pps baseline rbtree (match on first field only): 2950341pps set with 1000 full, ranged entries: 2304165pps port,net [ OK ] baseline (drop from netdev hook): 10143615pps baseline hash (non-ranged entries): 6135776pps baseline rbtree (match on first field only): 4311934pps set with 100 full, ranged entries: 4131471pps net6,port [ OK ] baseline (drop from netdev hook): 9730404pps baseline hash (non-ranged entries): 4809557pps baseline rbtree (match on first field only): 1501699pps set with 1000 full, ranged entries: 1092557pps port,proto [ OK ] baseline (drop from netdev hook): 10812426pps baseline hash (non-ranged entries): 6929353pps baseline rbtree (match on first field only): 3027105pps set with 30000 full, ranged entries: 284147pps net6,port,mac [ OK ] baseline (drop from netdev hook): 9660114pps baseline hash (non-ranged entries): 3778877pps baseline rbtree (match on first field only): 3179379pps set with 10 full, ranged entries: 2082880pps net6,port,mac,proto [ OK ] baseline (drop from netdev hook): 9718324pps baseline hash (non-ranged entries): 3799021pps baseline rbtree (match on first field only): 1506689pps set with 1000 full, ranged entries: 783810pps net,mac [ OK ] baseline (drop from netdev hook): 10190029pps baseline hash (non-ranged entries): 5172218pps baseline rbtree (match on first field only): 2946863pps set with 1000 full, ranged entries: 1279122pps v4: - fix build for 32-bit architectures: 64-bit division needs div_u64() (kbuild test robot ) v3: - rework interface for field length specification, NFT_SET_SUBKEY disappears and information is stored in description - remove scratch area to store closing element of ranges, as elements now come with an actual attribute to specify the upper range limit (Pablo Neira Ayuso) - also remove pointer to 'start' element from mapping table, closing key is now accessible via extension data - use bytes right away instead of bits for field lengths, this way we can also double the inner loop of the lookup function to take care of upper and lower bits in a single iteration (minor performance improvement) - make it clearer that set operations are actually atomic API-wise, but we can't e.g. implement flush() as one-shot action - fix type for 'dup' in nft_pipapo_insert(), check for duplicates only in the next generation, and in general take care of differentiating generation mask cases depending on the operation (Pablo Neira Ayuso) - report C implementation matching rate in commit message, so that AVX2 implementation can be compared (Pablo Neira Ayuso) v2: - protect access to scratch maps in nft_pipapo_lookup() with local_bh_disable/enable() (Florian Westphal) - drop rcu_read_lock/unlock() from nft_pipapo_lookup(), it's already implied (Florian Westphal) - explain why partial allocation failures don't need handling in pipapo_realloc_scratch(), rename 'm' to clone and update related kerneldoc to make it clear we're not operating on the live copy (Florian Westphal) - add expicit check for priv->start_elem in nft_pipapo_insert() to avoid ending up in nft_pipapo_walk() with a NULL start element, and also zero it out in every operation that might make it invalid, so that insertion doesn't proceed with an invalid element (Florian Westphal) Signed-off-by: Stefano Brivio Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: Support for sets with multiple ranged fields

2020-01-27T07:54:30Z

Introduce a new nested netlink attribute, NFTA_SET_DESC_CONCAT, used to specify the length of each field in a set concatenation. This allows set implementations to support concatenation of multiple ranged items, as they can divide the input key into matching data for every single field. Such set implementations would be selected as they specify support for NFT_SET_INTERVAL and allow desc->field_count to be greater than one. Explicitly disallow this for nft_set_rbtree. In order to specify the interval for a set entry, userspace would include in NFTA_SET_DESC_CONCAT attributes field lengths, and pass range endpoints as two separate keys, represented by attributes NFTA_SET_ELEM_KEY and NFTA_SET_ELEM_KEY_END. While at it, export the number of 32-bit registers available for packet matching, as nftables will need this to know the maximum number of field lengths that can be specified. For example, "packets with an IPv4 address between 192.0.2.0 and 192.0.2.42, with destination port between 22 and 25", can be expressed as two concatenated elements: NFTA_SET_ELEM_KEY: 192.0.2.0 . 22 NFTA_SET_ELEM_KEY_END: 192.0.2.42 . 25 and NFTA_SET_DESC_CONCAT attribute would contain: NFTA_LIST_ELEM NFTA_SET_FIELD_LEN: 4 NFTA_LIST_ELEM NFTA_SET_FIELD_LEN: 2 v4: No changes v3: Complete rework, NFTA_SET_DESC_CONCAT instead of NFTA_SET_SUBKEY v2: No changes Signed-off-by: Stefano Brivio Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: add NFTA_SET_ELEM_KEY_END attribute

2020-01-27T07:54:30Z

Add NFTA_SET_ELEM_KEY_END attribute to convey the closing element of the interval between kernel and userspace. This patch also adds the NFT_SET_EXT_KEY_END extension to store the closing element value in this interval. v4: No changes v3: New patch [sbrivio: refactor error paths and labels; add corresponding nft_set_ext_type for new key; rebase] Signed-off-by: Pablo Neira Ayuso

netfilter: flowtable: refresh flow if hardware offload fails

2020-01-16T14:51:52Z

If nf_flow_offload_add() fails to add the flow to hardware, then the NF_FLOW_HW_REFRESH flag bit is set and the flow remains in the flowtable software path. If flowtable hardware offload is enabled, this patch enqueues a new request to offload this flow to hardware. Signed-off-by: Pablo Neira Ayuso

netfilter: flowtable: add nf_flowtable_hw_offload() helper function

2020-01-16T14:51:51Z

This function checks for the NF_FLOWTABLE_HW_OFFLOAD flag, meaning that the flowtable hardware offload is enabled. Signed-off-by: Pablo Neira Ayuso

netfilter: flowtable: use atomic bitwise operations for flow flags

2020-01-16T14:51:50Z

Originally, all flow flag bits were set on only from the workqueue. With the introduction of the flow teardown state and hardware offload this is no longer true. Let's be safe and use atomic bitwise operation to operation with flow flags. Fixes: 59c466dd68e7 ("netfilter: nf_flow_table: add a new flow state for tearing down offloading") Signed-off-by: Pablo Neira Ayuso

netfilter: flowtable: remove dying bit, use teardown bit instead

2020-01-16T14:51:49Z

The dying bit removes the conntrack entry if the netdev that owns this flow is going down. Instead, use the teardown mechanism to push back the flow to conntrack to let the classic software path decide what to do with it. Signed-off-by: Pablo Neira Ayuso

netfilter: flowtable: add nf_flowtable_time_stamp

2020-01-06T09:30:46Z

This patch adds nf_flowtable_time_stamp and updates the existing code to use it. This patch is also implicitly fixing up hardware statistic fetching via nf_flow_offload_stats() where casting to u32 is missing. Use nf_flow_timeout_delta() to fix this. Fixes: c29f74e0df7a ("netfilter: nf_flow_table: hardware offload support") Signed-off-by: Pablo Neira Ayuso Acked-by: wenxu

treewide: Use sizeof_field() macro

2019-12-09T18:36:44Z

Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except at places where these are defined. Later patches will remove the unused definition of FIELD_SIZEOF(). This patch is generated using following script: EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h" git grep -l -e "\bFIELD_SIZEOF\b" | while read file; do if [[ "$file" =~ $EXCLUDE_FILES ]]; then continue fi sed -i -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file; done Signed-off-by: Pankaj Bharadiya Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com Co-developed-by: Kees Cook Signed-off-by: Kees Cook Acked-by: David Miller # for net

netfilter: nf_tables: constify nft_reg_load{8, 16, 64}()

2019-11-20T19:21:34Z

This patch constifies the pointer to source register data that is passed as an input parameter. Signed-off-by: Pablo Neira Ayuso Signed-off-by: David S. Miller