There are number of radix consumers in kernel land (pf,ipfw,nfs,route)
with different requirements. In fact, first 3 don't have _any_ requirements
and first 2 does not use radix locking. On the other hand, routing
structure do have these requirements (rnh_gen, multipath, custom
to-be-added control plane functions, different locking).
Additionally, radix should not known anything about its consumers internals.
So, radix code now uses tiny 'struct radix_head' structure along with
internal 'struct radix_mask_head' instead of 'struct radix_node_head'.
Existing consumers still uses the same 'struct radix_node_head' with
slight modifications: they need to pass pointer to (embedded)
'struct radix_head' to all radix callbacks.
Routing code now uses new 'struct rib_head' with different locking macro:
RADIX_NODE_HEAD prefix was renamed to RIB_ (which stands for routing
information base).
New net/route_var.h header was added to hold routing subsystem internal
data. 'struct rib_head' was placed there. 'struct rtentry' will also
be moved there soon.
compiled into the kernel. Ideally lots more code would just not
be called (or compiled in) in that case but that requires a lot
more surgery. For now try to make IP-less kernels compile again.
Main user-visible changes are related to tables:
* Tables are now identified by names, not numbers.
There can be up to 65k tables with up to 63-byte long names.
* Tables are now set-aware (default off), so you can switch/move
them atomically with rules.
* More functionality is supported (swap, lock, limits, user-level lookup,
batched add/del) by generic table code.
* New table types are added (flow) so you can match multiple packet fields at once.
* Ability to add different type of lookup algorithms for particular
table type has been added.
* New table algorithms are added (cidr:hash, iface:array, number:array and
flow:hash) to make certain types of lookup more effective.
* Table value are now capable of holding multiple data fields for
different tablearg users
Performance changes:
* Main ipfw lock was converted to rmlock
* Rule counters were separated from rule itself and made per-cpu.
* Radix table entries fits into 128 bytes
* struct ip_fw is now more compact so more rules will fit into 64 bytes
* interface tables uses array of existing ifindexes for faster match
ABI changes:
All functionality supported by old ipfw(8) remains functional.
Old & new binaries can work together with the following restrictions:
* Tables named other than ^\d+$ are shown as table(65535) in
ruleset in old binaries
Internal changes:.
Changing table ids to numbers resulted in format modification for
most sockopt codes. Old sopt format was compact, but very hard to
extend (no versioning, inability to add more opcodes), so
* All relevant opcodes were converted to TLV-based versioned IP_FW3-based codes.
* The remaining opcodes were also converted to be able to eliminate
all older opcodes at once
* All IP_FW3 handlers uses special API instead of calling sooptcopy*
directly to ease adding another communication methods
* struct ip_fw is now different for kernel and userland
* tablearg value has been changed to 0 to ease future extensions
* table "values" are now indexes in special value array which
holds extended data for given index
* Batched add/delete has been added to tables code
* Most changes has been done to permit batched rule addition.
* interface tracking API has been added (started on demand)
to permit effective interface tables operations
* O(1) skipto cache, currently turned off by default at
compile-time (eats 512K).
* Several steps has been made towards making libipfw:
* most of new functions were separated into "parse/prepare/show
and actuall-do-stuff" pieces (already merged).
* there are separate functions for parsing text string into "struct ip_fw"
and printing "struct ip_fw" to supplied buffer (already merged).
* Probably some more less significant/forgotten features
MFC after: 1 month
Sponsored by: Yandex LLC
* Ensure we're flushing entries without any locks held.
* Free memory in (rare) case when interface tracker fails to register ifp.
* Add KASSERT on table values refcounts.
This is the last major change in given branch.
Kernel changes:
* Use 64-bytes structures to hold multi-value variables.
* Use shared array to hold values from all tables (assume
each table algo is capable of holding 32-byte variables).
* Add some placeholders to support per-table value arrays in future.
* Use simple eventhandler-style API to ease the process of adding new
table items. Currently table addition may required multiple UH drops/
acquires which is quite tricky due to atomic table modificatio/swap
support, shared array resize, etc. Deal with it by calling special
notifier capable of rolling back state before actually performing
swap/resize operations. Original operation then restarts itself after
acquiring UH lock.
* Bump all objhash users default values to at least 64
* Fix custom hashing inside objhash.
Userland changes:
* Add support for dumping shared value array via "vlist" internal cmd.
* Some small print/fill_flags dixes to support u32 values.
* valtype is now bitmask of
<skipto|pipe|fib|nat|dscp|tag|divert|netgraph|limit|ipv4|ipv6>.
New values can hold distinct values for each of this types.
* Provide special "legacy" type which assumes all values are the same.
* More helpers/docs following..
Some examples:
3:41 [1] zfscurr0# ipfw table mimimi create valtype skipto,limit,ipv4,ipv6
3:41 [1] zfscurr0# ipfw table mimimi info
+++ table(mimimi), set(0) +++
kindex: 2, type: addr
references: 0, valtype: skipto,limit,ipv4,ipv6
algorithm: addr:radix
items: 0, size: 296
3:42 [1] zfscurr0# ipfw table mimimi add 10.0.0.5 3000,10,10.0.0.1,2a02:978:2::1
added: 10.0.0.5/32 3000,10,10.0.0.1,2a02:978:2::1
3:42 [1] zfscurr0# ipfw table mimimi list
+++ table(mimimi), set(0) +++
10.0.0.5/32 3000,0,10.0.0.1,2a02:978:2::1
own hash/compare functions.
* Add requirement for table algorithms to copy "valie" field in @add
callback instead of "prepare_add".
* Document existing requirement for table algorithms to store value
of deleted record to @tei.
* Use different approach to ensure algo has enough space to store N elements:
- explicitly ask algo (under UH_WLOCK) before/after insertion. This (along
with existing reallocation callbacks) really guarantees us that it is safe
to insert N elements at once while holding UH_WLOCK+WLOCK.
- remove old aflags/flags approach
Kernel changes:
* Add TEI_FLAGS_DONTADD entry flag to indicate that insert is not possible
* Support given flag in all algorithms
* Add "limit" field to ipfw_xtable_info
* Add actual limiting code into add_table_entry()
Userland changes:
* Add "limit" option as "create" table sub-option. Limit modification
is currently impossible.
* Print human-readable errors in table enry addition/deletion code.
* Add "flow:hash" algorithm
Kernel changes:
* Add O_IP_FLOW_LOOKUP opcode to support "flow" lookups
* Add IPFW_TABLE_FLOW table type
* Add "struct tflow_entry" as strage for 6-tuple flows
* Add "flow:hash" algorithm. Basically it is auto-growing chained hash table.
Additionally, we store mask of fields we need to compare in each instance/
* Increase ipfw_obj_tentry size by adding struct tflow_entry
* Add per-algorithm stat (ifpw_ta_tinfo) to ipfw_xtable_info
* Increase algoname length: 32 -> 64 (algo options passed there as string)
* Assume every table type can be customized by flags, use u8 to store "tflags" field.
* Simplify ipfw_find_table_entry() by providing @tentry directly to algo callback.
* Fix bug in cidr:chash resize procedure.
Userland changes:
* add "flow table(NAME)" syntax to support n-tuple checking tables.
* make fill_flags() separate function to ease working with _s_x arrays
* change "table info" output to reflect longer "type" fields
Syntax:
ipfw table fl2 create type flow:[src-ip][,proto][,src-port][,dst-ip][dst-port] [algo flow:hash]
Examples:
0:02 [2] zfscurr0# ipfw table fl2 create type flow:src-ip,proto,dst-port algo flow:hash
0:02 [2] zfscurr0# ipfw table fl2 info
+++ table(fl2), set(0) +++
kindex: 0, type: flow:src-ip,proto,dst-port
valtype: number, references: 0
algorithm: flow:hash
items: 0, size: 280
0:02 [2] zfscurr0# ipfw table fl2 add 2a02:6b8::333,tcp,443 45000
0:02 [2] zfscurr0# ipfw table fl2 add 10.0.0.92,tcp,80 22000
0:02 [2] zfscurr0# ipfw table fl2 list
+++ table(fl2), set(0) +++
2a02:6b8::333,6,443 45000
10.0.0.92,6,80 22000
0:02 [2] zfscurr0# ipfw add 200 count tcp from me to 78.46.89.105 80 flow 'table(fl2)'
00200 count tcp from me to 78.46.89.105 dst-port 80 flow table(fl2)
0:03 [2] zfscurr0# ipfw show
00200 0 0 count tcp from me to 78.46.89.105 dst-port 80 flow table(fl2)
65535 617 59416 allow ip from any to any
0:03 [2] zfscurr0# telnet -s 10.0.0.92 78.46.89.105 80
Trying 78.46.89.105...
..
0:04 [2] zfscurr0# ipfw show
00200 5 272 count tcp from me to 78.46.89.105 dst-port 80 flow table(fl2)
65535 682 66733 allow ip from any to any
Kernel changes:
* s/IPFW_TABLE_U32/IPFW_TABLE_NUMBER/
* Force "lookup <port|uid|gid|jid>" to be IPFW_TABLE_NUMBER
* Support "lookup" method for number tables
* Add number:array algorihm (i32 as key, auto-growing).
Userland changes:
* Support named tables in "lookup <tag> Table"
* Fix handling of "table(NAME,val)" case
* Support printing "number" table data.
Algorithm works with both IPv4 and IPv6 prefixes, /32 and /128
ranges are assumed by default.
It works the following way: input IP address is masked to specified
mask, hashed and searched inside hash bucket.
Current implementation does not support "lookup" method and hash auto-resize.
This will be changed soon.
some examples:
ipfw table mi_test2 create type cidr algo cidr:hash
ipfw table mi_test create type cidr algo "cidr:hash masks=/30,/64"
ipfw table mi_test2 info
+++ table(mi_test2), set(0) +++
type: cidr, kindex: 7
valtype: number, references: 0
algorithm: cidr:hash
items: 0, size: 220
ipfw table mi_test info
+++ table(mi_test), set(0) +++
type: cidr, kindex: 6
valtype: number, references: 0
algorithm: cidr:hash masks=/30,/64
items: 0, size: 220
ipfw table mi_test add 10.0.0.5/30
ipfw table mi_test add 10.0.0.8/30
ipfw table mi_test add 2a02:6b8:b010::1/64 25
ipfw table mi_test list
+++ table(mi_test), set(0) +++
10.0.0.4/30 0
10.0.0.8/30 0
2a02:6b8:b010::/64 25
* Rewrite interface tables to use interface indexes
Kernel changes:
* Add generic interface tracking API:
- ipfw_iface_ref (must call unlocked, performs lazy init if needed, allocates
state & bumps ref)
- ipfw_iface_add_ntfy(UH_WLOCK+WLOCK, links comsumer & runs its callback to
update ifindex)
- ipfw_iface_del_ntfy(UH_WLOCK+WLOCK, unlinks consumer)
- ipfw_iface_unref(unlocked, drops reference)
Additionally, consumer callbacks are called in interface withdrawal/departure.
* Rewrite interface tables to use iface tracking API. Currently tables are
implemented the following way:
runtime data is stored as sorted array of {ifidx, val} for existing interfaces
full data is stored inside namedobj instance (chained hashed table).
* Add IP_FW_XIFLIST opcode to dump status of tracked interfaces
* Pass @chain ptr to most non-locked algorithm callbacks:
(prepare_add, prepare_del, flush_entry ..). This may be needed for better
interaction of given algorithm an other ipfw subsystems
* Add optional "change_ti" algorithm handler to permit updating of
cached table_info pointer (happens in case of table_max resize)
* Fix small bug in ipfw_list_tables()
* Add badd (insert into sorted array) and bdel (remove from sorted array) funcs
Userland changes:
* Add "iflist" cmd to print status of currently tracked interface
* Add stringnum_cmp for better interface/table names sorting
* Add resize callbacks for upcoming table-based algorithms.
Kernel changes:
* s/ipfw_modify_table/ipfw_manage_table_ent/
* Simplify add_table_entry(): make table creation a separate piece of code.
Do not perform creation if not in "compat" mode.
* Add ability to perform modification of algorithm state (like table resize).
The following callbacks were added:
- prepare_mod (allocate new state, without locks)
- fill_mod (UH_WLOCK, copy old state to new one)
- modify (UH_WLOCK + WLOCK, switch state)
- flush_mod (no locks, flushes allocated data)
Given callbacks are called if table modification has been requested by add or
delete callbacks. Additional u64 tc->'flags' field was added to pass these
requests.
* Change add/del table ent format: permit adding/removing multiple entries
at once (only 1 supported at the moment).
Userland changes:
* Auto-create tables with warning
Since old structures had _value as the last field,
every table match required 3 cache lines instead of 2.
Fix this by
- using the fact that supplied masks are suplicated inside radix
- using lightweigth sa_in6 structure as key for IPv6
Before (amd64):
sizeof(table_entry): 136
sizeof(table_xentry): 160
After (amd64):
sizeof(radix_cidr_entry): 120
sizeof(radix_cidr_xentry): 128
sizeof(radix_iface): 128
* Fix memory leak for table entry update
* Do some more sanity checks while deleting entry
* Do not store masks for host routes
Sponsored by: Yandex LLC
Kernel changes:
* Change dump format for dynamic states:
each state is now stored inside ipfw_obj_dyntlv
last dynamic state is indicated by IPFW_DF_LAST flag
* Do not perform sooptcopyout() for !SOPT_GET requests.
Userland changes:
* Introduce foreach_state() function handler to ease work
with different states passed by ipfw_dump_config().
* Bump table dump format preserving old ABI.
Kernel size:
* Add IP_FW_TABLE_XFIND to handle "lookup" request from userland.
* Add ta_find_tentry() algorithm callbacks/handlers to support lookups.
* Fully switch to ipfw_obj_tentry for various table dumps:
algorithms are now required to support the latest (ipfw_obj_tentry) entry
dump format, the rest is handled by generic dump code.
IP_FW_TABLE_XLIST opcode version bumped (0 -> 1).
* Eliminate legacy ta_dump_entry algo handler:
dump_table_entry() converts data from current to legacy format.
Userland side:
* Add "lookup" table parameter.
* Change the way table type is guessed: call table_get_info() first,
and check value for IPv4/IPv6 type IFF table does not exist.
* Fix table_get_list(): do more tries if supplied buffer is not enough.
* Sparate table_show_entry() from table_show_list().
Kernel changes:
* Introduce ipfw_obj_tentry table entry structure to force u64 alignment.
* Support "update-on-existing-key" "add" bahavior (TEI_FLAGS_UPDATED).
* Use "subtype" field to distingush between IPv4 and IPv6 table records
instead of previous hack.
* Add value type (vtype) field for kernel tables. Current types are
number,ip and dscp
* Fix sets mask retrieval for old binaries
* Fix crash while using interface tables
Userland changes:
* Switch ipfw_table_handler() to use named-only tables.
* Add "table NAME create [type {cidr|iface|u32} [valtype {number|ip|dscp}] ..."
* Switch ipfw_table_handler to match_token()-based parser.
* Switch ipfw_sets_handler to use new ipfw_get_config() for mask retrieval.
* Allow ipfw set X table ... syntax to permit using per-set table namespaces.
* Add 'algoname' string to ipfw_xtable_info permitting to specify lookup
algoritm with parameters.
* Rework part of ipfw_rewrite_table_uidx()
Sponsored by: Yandex LLC