Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Merge helper fib* functions used for basic lookups.

Vast majority of rtalloc(9) users require only basic info from
route table (e.g. "does the rtentry interface match with the interface
I have?". "what is the MTU?", "Give me the IPv4 source address to use",
etc..).
Instead of hand-rolling lookups, checking if rtentry is up, valid,
dealing with IPv6 mtu, finding "address" ifp (almost never done right),
provide easy-to-use API hiding all the complexity and returning the
needed info into small on-stack structure.

This change also helps hiding route subsystem internals (locking, direct
rtentry accesses).
Additionaly, using this API improves lookup performance since rtentry is not
locked.
(This is safe, since all the rtentry changes happens under both radix WLOCK
and rtentry WLOCK).

Sponsored by: Yandex LLC

Add sa6_checkzone_ifp() function. It checks correctness of struct
sockaddr_in6, usually obtained from the user level through ioctl.
It initializes sin6_scope_id using given interface.

Sponsored by: Yandex LLC

Introduce new scope related functions.

* new macro to remove magic number - IPV6_ADDR_SCOPES_COUNT;
* sa6_checkzone() - this function checks sockaddr_in6 structure
for correctness of sin6_scope_id. It also can fill correct
value sometimes.
* in6_getscopezone() - this function returns scope zone id for
specified interface and scope.
* in6_getlinkifnet() - this function returns struct ifnet for
corresponding zone id of link-local scope.

Obtained from: Yandex LLC
Sponsored by: Yandex LLC

Add some missing checks for unsupported interfaces (e.g. pflog(4)) when
handling ioctls. While here, remove duplicated checks for a NULL ifp in
in6_control(): this check is already done near the beginning of the
function.

PR: 189117
Reviewed by: hrs
MFC after: 2 weeks

- Move definition of V_deembed_scopeid to scope6_var.h.
- Deembed scope id in L3 address in in6_lltable_dump().
- Simplify scope id recovery in rtsock routines.
- Remove embedded scope id handling in ndp(8) and route(8) completely.

Remove __P.

Submitted by: kevlo
Reviewed by: md5(1)
MFC after: 2 months

MFp4 bz_ipv6_fast:

Introduce in6_getscope() to allow more effective checksum
computations without the need to copy the address to clear the
scope.

Sponsored by: The FreeBSD Foundation
Sponsored by: iXsystems

Reviewed by: gnn (as part of the whole)
MFC After: 3 days

Remove a declaration to a non-existent function.

MFC after: 3 days
Sponsored by: The FreeBSD Foundation

Clean up VCS Ids.

scope cleanup. with this change
- most of the kernel code will not care about the actual encoding of
scope zone IDs and won't touch "s6_addr16[1]" directly.
- similarly, most of the kernel code will not care about link-local
scoped addresses as a special case.
- scope boundary check will be stricter. For example, the current
*BSD code allows a packet with src=::1 and dst=(some global IPv6
address) to be sent outside of the node, if the application do:
s = socket(AF_INET6);
bind(s, "::1");
sendto(s, some_global_IPv6_addr);
This is clearly wrong, since ::1 is only meaningful within a single
node, but the current implementation of the *BSD kernel cannot
reject this attempt.

Submitted by: JINMEI Tatuya <jinmei__at__isl.rdc.toshiba.co.jp>
Obtained from: KAME

/* -> /*- for license, minor formatting changes, separate for KAME

- add dom_if{attach,detach} framework.
- transition to use ifp->if_afdata.

Obtained from: KAME

- typo in comment
- style
- ANSIfy
(there is no functional change.)

Obtained from: KAME

sync with kame tree as of july00. tons of bug fixes/improvements.

API changes:
- additional IPv6 ioctls
- IPsec PF_KEY API was changed, it is mandatory to upgrade setkey(8).
(also syntax change)