Switch direct rt fields access in rtsock.c to newly-create field acessors.

rtsock code was build around the assumption that each rtentry record
in the system radix tree is a ready-to-use sockaddr.

Switch direct rt fields access in rtsock.c to newly-create field acessors.

rtsock code was build around the assumption that each rtentry record
in the system radix tree is a ready-to-use sockaddr. This assumptions
turned out to be not quite true:
* masks have their length tweaked, so we have rtsock_fix_netmask() hack
* IPv6 addresses have their scope embedded, so we have another explicit
deembedding hack.

Change the code to decouple rtentry internals from rtsock code using
newly-created rtentry accessors. This will allow to eventually eliminate
both of the hacks and change rtentry dst/mask format.

Differential Revision: https://reviews.freebsd.org/D27451

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Remove RADIX_MPATH config option.

ROUTE_MPATH is the new config option controlling new multipath routing
implementation. Remove the last pieces of RADIX_MPATH-related code and
the config option.

Remove RADIX_MPATH config option.

ROUTE_MPATH is the new config option controlling new multipath routing
implementation. Remove the last pieces of RADIX_MPATH-related code and
the config option.

Reviewed by: glebius
Differential Revision: https://reviews.freebsd.org/D27244

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Fix route flags update during RTM_CHANGE.
Nexthop lookup was not consireding rt_flags when doing
structure comparison, which lead to an original nexthop
selection when changing flags. Fix the case

Fix route flags update during RTM_CHANGE.
Nexthop lookup was not consireding rt_flags when doing
structure comparison, which lead to an original nexthop
selection when changing flags. Fix the case by adding
rt_flags field into comparison and rearranging nhop_priv
fields to allow for efficient matching.
Fix `route change X/Y flags` case - recent changes
disallowed specifying RTF_GATEWAY flag without actual gateway.
It turns out, route(8) fills in RTF_GATEWAY by default, unless
-interface flag is specified. Fix regression by clearing
RTF_GATEWAY flag instead of failing.
Fix route flag reporting in RTM_CHANGE messages by explicitly
updating rtm_flags after operation competion.
Add IPv4/IPv6 tests for flag-only route changes.

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Remove ROUTE_MPATH-related warnings introduced in r366390.

Reported by: mjg

Introduce scalable route multipath.

This change is based on the nexthop objects landed in D24232.

The change introduces the concept of nexthop groups.
Each group contains the collection of nexthops

Introduce scalable route multipath.

This change is based on the nexthop objects landed in D24232.

The change introduces the concept of nexthop groups.
Each group contains the collection of nexthops with their
relative weights and a dataplane-optimized structure to enable
efficient nexthop selection.

Simular to the nexthops, nexthop groups are immutable. Dataplane part
gets compiled during group creation and is basically an array of
nexthop pointers, compiled w.r.t their weights.

With this change, `rt_nhop` field of `struct rtentry` contains either
nexthop or nexthop group. They are distinguished by the presense of
NHF_MULTIPATH flag.
All dataplane lookup functions returns pointer to the nexthop object,
leaving nexhop groups details inside routing subsystem.

User-visible changes:

The change is intended to be backward-compatible: all non-mpath operations
should work as before with ROUTE_MPATH and net.route.multipath=1.

All routes now comes with weight, default weight is 1, maximum is 2^24-1.

Current maximum multipath group width is statically set to 64.
This will become sysctl-tunable in the followup changes.

Using functionality:
* Recompile kernel with ROUTE_MPATH
* set net.route.multipath to 1

route add -6 2001:db8::/32 2001:db8::2 -weight 10
route add -6 2001:db8::/32 2001:db8::3 -weight 20

netstat -6On

Nexthop groups data

Internet6:
GrpIdx NhIdx Weight Slots Gateway Netif Refcnt
1 ------- ------- ------- --------------------------------------- --------- 1
13 10 1 2001:db8::2 vlan2
14 20 2 2001:db8::3 vlan2

Next steps:
* Land outbound hashing for locally-originated routes ( D26523 ).
* Fix net/bird multipath (net/frr seems to work fine)
* Add ROUTE_MPATH to GENERIC
* Set net.route.multipath=1 by default

Tested by: olivier
Reviewed by: glebius
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D26449

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Rework part of routing code to reduce difference to D26449.

* Split rt_setmetrics into get_info_weight() and rt_set_expire_info(),
as these two can be applied at different entities and at different

Rework part of routing code to reduce difference to D26449.

* Split rt_setmetrics into get_info_weight() and rt_set_expire_info(),
as these two can be applied at different entities and at different times.
* Start filling route weight in route change notifications
* Pass flowid to UDP/raw IP route lookups
* Rework nd6_subscription_cb() and sysctl_dumpentry() to prepare for the fact
that rtentry can contain multiple nexthops.

Differential Revision: https://reviews.freebsd.org/D26497

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rtsock.c: remove extraneous space

Submitted by: Neel Chauhan <neel AT neelc DOT org>
Differential Revision: https://reviews.freebsd.org/D26249

net: clean up empty lines in .c and .h files

Move net/route/shared.h definitions to net/route/route_var.h.

No functional changes.

net/route/shared.h was created in the inital phases of nexthop conversion.
It was intended to serve the same pur

Move net/route/shared.h definitions to net/route/route_var.h.

No functional changes.

net/route/shared.h was created in the inital phases of nexthop conversion.
It was intended to serve the same purpose as route_var.h - share definitions
of functions and structures between the routing subsystem components. At
that time route_var.h was included by many files external to the routing
subsystem, which largerly defeats its purpose.

As currently this is not the case anymore and amount of route_var.h includes
is roughly the same as shared.h, retire the latter in favour of the former.

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Remove RT_LOCK mutex from rte.

rtentry lock traditionally served 2 purposed: first was protecting refcounts,
the second was assuring consistent field access/changes.
Since route nexthop introductio

Remove RT_LOCK mutex from rte.

rtentry lock traditionally served 2 purposed: first was protecting refcounts,
the second was assuring consistent field access/changes.
Since route nexthop introduction, the need for the former disappeared and
the need for the latter reduced.
To be more precise, the following rte field are mutable:

rt_nhop (nexthop pointer, updated with RIB_WLOCK, passed in rib_cmd_info)
rte_flags (only RTF_HOST and RTF_UP, where RTF_UP gets changed at rte removal)
rt_weight (relative weight, updated with RIB_WLOCK, passed in rib_cmd_info)
rt_expire (time when rte deletion is scheduled, updated with RIB_WLOCK)
rt_chain (deletion chain pointer, updated with RIB_WLOCK)
All of them are updated under RIB_WLOCK, so the only remaining concern is the reading.

rt_nhop and rt_weight (addressed in this review) are read under rib lock and
stored in the rib_cmd_info, so the caller has no problem with consitency.
rte_flags is currently read unlocked in rtsock reporting (however the scope
is only RTF_UP flag, which is pretty static).
rt_expire is currently read unlocked in rtsock reporting.
rt_chain accesses are safe, as this is only used at route deletion.

rt_expire and rte_flags reads will be dealt in a separate reviews soon.

Differential Revision: https://reviews.freebsd.org/D26162

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Rename rt_flags to rte_flags && reduce number of rt_nhop accesses.

No functional changes.

Most of the routing flags are stored in the netxtop instead of rtentry.
Rename rt->rt_flags to rt->rte_flag

Rename rt_flags to rte_flags && reduce number of rt_nhop accesses.

No functional changes.

Most of the routing flags are stored in the netxtop instead of rtentry.
Rename rt->rt_flags to rt->rte_flags to simplify reading/modifying code
checking routing flags.

In the new multipath code, rt->rt_nhop may actually point to nexthop group
instead of nhop. To ease transition, reduce the amount of rt->rt_nhop->...
accesses.

Differential Revision: https://reviews.freebsd.org/D26156

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Make net.inet6.ip6.deembed_scopeid behaviour default & remove sysctl.

Submitted by: Neel Chauhan <neel AT neelc DOT org>
Differential Revision: https://reviews.freebsd.org/D25637

Switch rtsock code to using newly-create rib_action() KPI call.

This simplifies the code and allows to further split rtentry and nexthop,
removing one of the blockers for multipath code introductio

Switch rtsock code to using newly-create rib_action() KPI call.

This simplifies the code and allows to further split rtentry and nexthop,
removing one of the blockers for multipath code introduction, described in
D24141.

Reviewed by: ae
Differential Revision: https://reviews.freebsd.org/D25192

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Use epoch(9) for rtentries to simplify control plane operations.

Currently the only reason of refcounting rtentries is the need to report
the rtable operation details immediately after the executio

Use epoch(9) for rtentries to simplify control plane operations.

Currently the only reason of refcounting rtentries is the need to report
the rtable operation details immediately after the execution.
Delaying rtentry reclamation allows to stop refcounting and simplify the code.
Additionally, this change allows to reimplement rib_lookup_info(), which
is used by some of the customers to get the matching prefix along
with nexthops, in more efficient way.

The change keeps per-vnet rtzone uma zone. It adds nh_vnet field to
nhop_priv to be able to reliably set curvnet even during vnet teardown.
Rest of the reference counting code will be removed in the D24867 .

Differential Revision: https://reviews.freebsd.org/D24866

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Embed dst sockaddr into rtentry and remove rte packet counter

Currently each rtentry has dst&gateway allocated separately from another zone,
bloating cache accesses.

Current 'struct rtentry' has 1

Embed dst sockaddr into rtentry and remove rte packet counter

Currently each rtentry has dst&gateway allocated separately from another zone,
bloating cache accesses.

Current 'struct rtentry' has 12 "mandatory" radix pointers in the beginning,
leaving 4 usable pointers/32 bytes in the first 2 cache lines (amd64).
Fields needed for the datapath are destination sockaddr and rt_nhop.

So far it doesn't look like there is other routable addressing protocol other
than IPv4/IPv6/MPLS, which uses keys longer than 20 bytes.
With that in mind, embed dst into struct rtentry, making the first 24 bytes
of rtentry within 128 bytes. That is enough to make IPv6 address within first
128 bytes.

It is still pretty easy to add code for supporting separately-allocated dst,
however it doesn't make a lot of sense in having such code without a use case.

As rS359823 moved the gateway to the nexthop structure, the dst embedding change
removes the need for any additional allocations done by rt_setgate().

Lastly, as a part of cleanup, remove counter(9) allocation code, as this field
is not used in packet processing anymore.

Reviewed by: ae
Differential Revision: https://reviews.freebsd.org/D24669

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Convert more rtentry field accesses into nhop fields accesses.

Continue routing subsystem conversion to nhop objects defined in r359823.
Use fields from nhop structure instead of "struct rtentry" fi

Convert more rtentry field accesses into nhop fields accesses.

Continue routing subsystem conversion to nhop objects defined in r359823.
Use fields from nhop structure instead of "struct rtentry" fields.
This is one of the last changes prior to removing rt_ifp, rt_ifa,
rt_gateway and rt_mtu from struct rtentry.

Differential Revision: https://reviews.freebsd.org/D24609

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Move route-specific ddb commands to route/route_ddb.c

Currently functionality resides in rtsock.c, which is a controlling
interface, partially external to the routing subsystem.
Additionally, DDB-s

Move route-specific ddb commands to route/route_ddb.c

Currently functionality resides in rtsock.c, which is a controlling
interface, partially external to the routing subsystem.
Additionally, DDB-supporting functionality is > 100SLOC, which deserves
a separate file.

Given that, move this functionality to a newly-created net/route/ subdir.

Reviewed by: cem
Differential Revision: https://reviews.freebsd.org/D24561

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Move route_temporal.c and route_var.h to net/route.

Nexthop objects implementation, defined in r359823,
introduced sys/net/route directory intended to hold all
routing-related code. Move recently-

Move route_temporal.c and route_var.h to net/route.

Nexthop objects implementation, defined in r359823,
introduced sys/net/route directory intended to hold all
routing-related code. Move recently-introduced route_temporal.c and
private route_var.h header there.

Differential Revision: https://reviews.freebsd.org/D24597

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Convert rtentry field accesses into nhop field accesses.

One of the goals of the new routing KPI defined in r359823 is to entirely
hide`struct rtentry` from the consumers. It will allow to improve

Convert rtentry field accesses into nhop field accesses.

One of the goals of the new routing KPI defined in r359823 is to entirely
hide`struct rtentry` from the consumers. It will allow to improve routing
subsystem internals and deliver more features much faster.

This commit is mostly mechanical change to eliminate direct struct rtentry
field accesses.

The only notable difference is AF_LINK gateway encoding.

AF_LINK gw is used in routing stack for operations with interface routes
and host loopback routes.
In the former case it indicates _some_ non-NULL gateway, as the interface
is the same as in rt_ifp in kernel and rtm_ifindex in rtsock reporting.
In the latter case the interface index inside gateway was used by the IPv6
datapath to verify address scope for link-local interfaces.

Kernel uses struct sockaddr_dl for this type of gateway. This structure
allows for specifying rich interface data, such as mac address and interface
name. However, this results in relatively large structure size - 52 bytes.
Routing stack fils in only 2 fields - sdl_index and sdl_type, which reside
in the first 8 bytes of the structure.

In the new KPI, struct nhop_object tries to be cache-efficient, hence
embodies gateway address inside the structure. In the AF_LINK case it
stores stortened version of the structure - struct sockaddr_dl_short,
which occupies 16 bytes. After D24340 changes, the data inside AF_LINK
gateway will not be used in the kernel at all, leaving rtsock as the only
potential concern.

The difference in rtsock reporting:

(old)
got message of size 240 on Thu Apr 16 03:12:13 2020
RTM_ADD: Add Route: len 240, pid: 0, seq 0, errno 0, flags:<UP,DONE,PINNED>
locks: inits:
sockaddrs: <DST,GATEWAY,NETMASK>
10.0.0.0 link#5 255.255.255.0

(new)
got message of size 200 on Sun Apr 19 09:46:32 2020
RTM_ADD: Add Route: len 200, pid: 0, seq 0, errno 0, flags:<UP,DONE,PINNED>
locks: inits:
sockaddrs: <DST,GATEWAY,NETMASK>
10.0.0.0 link#5 255.255.255.0

Note 40 bytes different (52-16 + alignment).
However, gateway is still a valid AF_LINK gateway with proper data filled in.

It is worth noting that these particular messages (interface routes) are mostly
ignored by routing daemons:
* bird/quagga/frr uses RTM_NEWADDR and ignores prefix route addition messages.
* quagga/frr ignores routes without gateway

More detailed overview on how rtsock messages are used by the
routing daemons to reconstruct the kernel view, can be found in D22974.

Differential Revision: https://reviews.freebsd.org/D24519

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Remove an duplicate definition of nhops_dump_sysctl()

One of the source files included both nhop.h and shared.h, leading to this
clashing.

Tested with: mips-gcc cross toolchain

Introduce nexthop objects and new routing KPI.

This is the foundational change for the routing subsytem rearchitecture.
More details and goals are available in https://reviews.freebsd.org/D24141 .

Introduce nexthop objects and new routing KPI.

This is the foundational change for the routing subsytem rearchitecture.
More details and goals are available in https://reviews.freebsd.org/D24141 .

This patch introduces concept of nexthop objects and new nexthop-based
routing KPI.

Nexthops are objects, containing all necessary information for performing
the packet output decision. Output interface, mtu, flags, gw address goes
there. For most of the cases, these objects will serve the same role as
the struct rtentry is currently serving.
Typically there will be low tens of such objects for the router even with
multiple BGP full-views, as these objects will be shared between routing
entries. This allows to store more information in the nexthop.

New KPI:

struct nhop_object *fib4_lookup(uint32_t fibnum, struct in_addr dst,
uint32_t scopeid, uint32_t flags, uint32_t flowid);
struct nhop_object *fib6_lookup(uint32_t fibnum, const struct in6_addr *dst6,
uint32_t scopeid, uint32_t flags, uint32_t flowid);

These 2 function are intended to replace all all flavours of
<in_|in6_>rtalloc[1]<_ign><_fib>, mpath functions and the previous
fib[46]-generation functions.

Upon successful lookup, they return nexthop object which is guaranteed to
exist within current NET_EPOCH. If longer lifetime is desired, one can
specify NHR_REF as a flag and get a referenced version of the nexthop.
Reference semantic closely resembles rtentry one, allowing sed-style conversion.

Additionally, another 2 functions are introduced to support uRPF functionality
inside variety of our firewalls. Their primary goal is to hide the multipath
implementation details inside the routing subsystem, greatly simplifying
firewalls implementation:

int fib4_lookup_urpf(uint32_t fibnum, struct in_addr dst, uint32_t scopeid,
uint32_t flags, const struct ifnet *src_if);
int fib6_lookup_urpf(uint32_t fibnum, const struct in6_addr *dst6, uint32_t scopeid,
uint32_t flags, const struct ifnet *src_if);

All functions have a separate scopeid argument, paving way to eliminating IPv6 scope
embedding and allowing to support IPv4 link-locals in the future.

Structure changes:
* rtentry gets new 'rt_nhop' pointer, slightly growing the overall size.
* rib_head gets new 'rnh_preadd' callback pointer, slightly growing overall sz.

Old KPI:
During the transition state old and new KPI will coexists. As there are another 4-5
decent-sized conversion patches, it will probably take a couple of weeks.
To support both KPIs, fields not required by the new KPI (most of rtentry) has to be
kept, resulting in the temporary size increase.
Once conversion is finished, rtentry will notably shrink.

More details:
* architectural overview: https://reviews.freebsd.org/D24141
* list of the next changes: https://reviews.freebsd.org/D24232

Reviewed by: ae,glebius(initial version)
Differential Revision: https://reviews.freebsd.org/D24232

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Mark more nodes as CTLFLAG_MPSAFE or CTLFLAG_NEEDGIANT (17 of many)

r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly mark

Mark more nodes as CTLFLAG_MPSAFE or CTLFLAG_NEEDGIANT (17 of many)

r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.

This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.

Mark all obvious cases as MPSAFE. All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT

Approved by: kib (mentor, blanket)
Commented by: kib, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D23718

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Fix rtsock route message generation for interface addresses.

Reviewed by: olivier
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D22974

Fix NOINET6 build broken by r356236.

MFC after: 2 weeks

Split gigantic rtsock route_output() into smaller functions.

Amount of changes to the original code has been intentionally minimised
to ease diffing.
The changes are mostly mechanical, with the foll

Split gigantic rtsock route_output() into smaller functions.

Amount of changes to the original code has been intentionally minimised
to ease diffing.
The changes are mostly mechanical, with the following exceptions:

* lltable handler is now called directly based of RTF_LLINFO flag presense.
* "report" logic for updating rtm in RTM_GET/RTM_DELETE has been simplified,
fixing several potential use-after-free cases in rt_addrinfo.
* llable asserts has been replaced with error-returning, preventing kernel
crashes when lltable gw af family is invalid (root required).

MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D22864

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