We don't need it for userboot, but it avoids issues with BIND_NOW, so
just provide it.  time(3) isn't defined but ends up being provided by
libc linked into the host process, which is generally fine.

PR:	262920
Reviewed by:	imp, jhb

(cherry picked from commit 660c1892d5c90500d37f98185326c6287b2b61be)

This is a change in preparation for stopping to use lorder.sh (D26044) and
instead assume that we have a linker newer than ~1990. Without lorder.sh
duplicates end up being passed to the linker when building .so files and this
can result in duplicate symbol definition errors.

There is one minor change: libcompiler_rt.a will no longer provide
gcc_personality_v0 and instead we now only have it in libgcc_eh.a/libgcc_s.so.
This matches GCC's behaviour.

Reviewed By:	emaste, cem
Differential Revision: https://reviews.freebsd.org/D26042

(cherry picked from commit 0b862b03998a292a18bcc7f9ac5b05c0303c5de3)

No functional changes intended.

MFC after:	1 week

(cherry picked from commit 5d5a6216645a6aefa8665c79bb761b754d74c067)

We should have nextboot feature implemented in libsa zfs code.
To get there, I have created zfs_nextboot() implementation based on
two sources, our current simple textual string based approach with added
structured boot label PAD structure from OpenZFS.

Secondly, all nvlist details are moved to separate source file and
restructured a bit. This is done to provide base support to add nvlist
add/update feature in followup updates.

And finally, the zfsboot/gptzfsboot disk access functions are swapped to
use libi386 and libsa.

(cherry picked from commit 3830659e99640001c09d26dfc0e1bbd77d919a62)
(cherry picked from commit a137f7997efc8a34da75a7643c8fade4be67e82c)
(cherry picked from commit 4583682ec14cc63f063b6769b7706af1891b0934)

Test is printing decimal value after prefix 0x.

(cherry picked from commit 96b2f9c996c82941b58eceaafe55eb696e8a5a4d)

allow to specify multiple -d options, test -d disk1 -d disk2 ..

(cherry picked from commit bcbb1e60a1c181310a7ce36af2c202fa789d03e5)

Stop setting PG_U in bootstrap mappings.

r359406, r359413-r359416, r359424-r359425, r359427, r359432-r359433,
r359443, r359675-r359678

Note: this is not necessarily a complete fix to get these programs to build
with -fno-common applied; further work may be needed in this branch.

r359389:
config(8): fixes for -fno-common

Move this handful of definitions into main.c, properly declare these as
extern in config.h. This fixes the config(8) build with -fno-common.

Unexplained in my previous commit to gas, -fno-common will become the
default in GCC10 and LLVM11, so it's worth addressing these in advance.

r359394:
MFV r359393: tcsh: import 6974bc35a5cd

This removes an extra variable definition that causes the -fno-common build
to fail, which will be a new default in GCC10/LLVM11.

r359397:
zfs: fix -fno-common issues

A similar (or identical?) fix has already landed in OpenZFS.

-fno-common will become the default in GCC10/LLVM11.

r359398:
sh: remove duplicate el definition

el is declared extern in myhistedit.h and defined in histedit.c. Remove the
duplicate definition in input.c to appease the -fno-common build.

-fno-common will become the default in GCC10/LLVM11.

r359399:
telnet: remove some duplicate definitions, mark terminaltype extern

Most of these were already properly declared and defined elsewhere, this is
effectively just a minor cleanup that fixes the -fno-common build.

-fno-common will become the default in GCC10/LLVM11.

r359403:
Revert 359399: telnet -fno-common bits

There was a large misfire from my local diff that I need to investigate, and
this version committed did not build.

r359404:
Re-apply r359399: telnet -fno-common fix

line and auth_level's redefinitions are just extraneous

telnetd will #define extern and then include ext.h to allocate storage for
all of these extern'd vars; however, two of them are actually defined in
libtelnet instead. Instead of doing an #ifdef extern dance around those
function pointers, just add an EXTERN macro to make it easier to
differentiate by sight which ones will get allocated in globals.c and which
ones are defined elsewhere.

r359406:
telnet: kill off remaining duplicate definition

r359413:
ipfilter: remove duplicate definition of 'thishost'

thishost is already defined in lib/initparse.c; no need for this one. This
fixes the ipfilter build with -fno-common.

-fno-common will become the default in GCC10/LLVM11.

r359414:
iscontrol: move definition of vflag/iscsidev to iscontrol.c

Mark the declaration extern as these are used elsewhere; this fixes the
build with -fno-common.

r359415:
userboot: mark host_fsops as extern

This is already defined elsewhere; mark this declaration extern to the fix
the -fno-common build.

r359416:
systat: remove redundant definition of kd

kd is already properly declared in extern.h and defined in main.c, rendering
this definition useless. This fixes the -fno-common build.

r359424:
openssh: -fno-common fix from upstream f47d72ddad

This is currently staged in vendor/ as part of the 8.0p1 import, which isn't
quite ready to land. Given that this is a simple one-line fix, apply it now
as the fallout will be pretty minimal.

-fno-common will become the default in GCC10/LLVM11.

r359425:
locate: fix -fno-common build

Just a single variable declaration to extern and define elsewhere here,
myctype.

-fno-common will become a default in GCC10/LLVM11.

r359427:
fsck_ffs/fsdb: fix -fno-common build

This one is also a small list:

- 3x duplicate definition (ufs2_zino, returntosingle, nflag)
- 5x 'needs extern', 3/5 of which are referenced in fsdb

-fno-common will become the default in GCC10/LLVM11.

r359432:
gdb: compile with -fcommon explicitly

As described in the comment, gdb relies on some of the linker magic that
happens with -fcommon. I suspect the life expectancy of gdb-in-base is low
enough that this isn't worth spending much time addressing, especially given
the vintage. Hit it with the -fcommon hammer so that it continues to just
work.

r359433:
bmake: fix -fno-common build

debug was declared extern, but debug_file was not; correct this and define
debug_file in main.c (as debug is) to fix the -fno-common build.

-fno-common will become the default with GCC10/LLVM11.

r359443:
MFV r359442: bmake: import -fno-common fix build back from upstream

sjg@ committed the local patch previously committed upstream; pull it in to
vendor/ to ease any potential stress of future imports.

r359675:
kqueue tests: fix -fno-common build

vnode_fd and kqfd are both shared among multiple CU; define them exactly
once.

In the case of vnode_fd, it was simply the declaration that needed
correction.

-fno-common will become the default in GCC10/LLVM11.

r359676:
ntpd: fix build with -fno-common

Only a small nit here: psl should be declared extern and defined exactly
once.

-fno-common will become the default in GCC10/LLVM11.

r359677:
yp*: fix -fno-common build

This is mostly two problems spread out far and wide:
- ypldap_process should be declared properly
- debug is defined differently in many programs

For the latter, just extern it and define it everywhere that actually needs
it. This mostly works out nicely for ^/libexec/ypxfr, which can remove the
assignment at the beginning of main in favor of defining it properly.

-fno-common will become the default in GCC10/LLVM11.

r359678:
indent: fix the -fno-common build

Spread the globals far and wide, hopefully to the files that make the most
sense.

-fno-common will become the default in GCC10/LLVM11.

The vectx API, computes the hash for verifying a file as it is read.
This avoids the overhead of reading files twice - once to verify, then
again to load.

For doing an install via loader, avoiding the need to rewind
large files is critical.

This API is only used for modules, kernel and mdimage as these are the
biggest files read by the loader.
The reduction in boot time depends on how expensive the I/O is
on any given platform.  On a fast VM we see 6% improvement.

For install via loader the first file to be verified is likely to be the
kernel, so some of the prep work (finding manifest etc) done by
verify_file() needs to be factored so it can be reused for
vectx_open().

For missing or unrecognized fingerprint entries, we fail
in vectx_open() unless verifying is disabled.

Otherwise fingerprint check happens in vectx_close() and
since this API is only used for files which must be verified
(VE_MUST) we panic if we get an incorrect hash.

Fix pkgfs stat so it satisfies libsecureboot

We need a valid st_dev, st_ino and st_mtime
to correctly track which files have been verified
and to update our notion of time.

ve_utc_set(): ignore utc if it would jump our current time
by more than VE_UTC_MAX_JUMP (20 years).

Allow testing of install command via userboot.
Need to fix its stat implementation too.

bhyveload also needs stat fixed - due to change to userboot.h

Call ve_error_get() from vectx_close() when hash is wrong.

Track the names of files we have hashed into pcr

For the purposes of measured boot, it is important
to be able to reproduce the hash reflected in
loader.ve.pcr
so loader.ve.hashed provides a list of names in the order they
were added.

Avoid unused vars when VE_ECDSA_HASH_AGAIN undefined

MFC of r358744 r358767 r359307 r355962

Reviewed by:	imp,tsoome,emaste
Sponsored by:	Juniper Networks
Differential Revision:	https://reviews.freebsd.org//D23827 https://reviews.freebsd.org//D24027

r345477:
Distinguish between "no partition" and "choose best partition" with a
constant.

The values of the d_slice and d_partition fields of a disk_devdesc have a
few values with special meanings in the disk_open() routine. Through various
evolutions of the loader code over time, a d_partition value of -1 has
meant both "use the first ufs partition found in the bsd label" and "don't
open a bsd partition at all, open the raw slice."

This defines a new special value of -2 to mean open the raw slice, and it
gives symbolic names to all the special values used in d_slice and
d_partition, and adjusts all existing uses of those fields to use the new
constants.

The phab review for this timed out without being accepted, but I'm still
citing it below because there is useful commentary there.

r346675:
Restore the ability to open a raw disk or partition in loader(8).

The disk_open() function searches for "the best partition" when slice and
partition information is not provided as part of the device name.  As of
r345477 the slice and partition fields of a disk_devdesc are initialized to
D_SLICEWILD and D_PARTWILD; in the past they were initialized to -1, which
was sometimes interpreted as meaning 'wildcard' and sometimes as 'open the
raw partition' depending on the context.  So as an unintended side effect of
r345477 it became basically impossible to ever open a disk or partition
without doing the 'best partition' search.  One visible effect of that was
the inability to open the raw disk to read the partition table correctly in
zfs_probe_dev(), leading to failures to find the zfs pool unless it was on
the first partition.

Now instead of always initializing slice and partition to wildcards, the
disk_parsedev() function initializes them based on the presence of a
path/file name following the device.  If there is any path or filename
following the ':' that ends the device name, then slice and partition are
initialized to D_SLICEWILD and D_PARTWILD.  If there is nothing after the
':' then it is considered to be a request to open the raw device or
partition itself (not a file stored within it), and the fields are
initialized to D_SLICENONE and D_PARTNONE.

With this change in place, all the tests in src/tools/boot are succesful
again, including the recently-added cases of booting from a zfs pool on
a partition other than slice 1 of the device.

r346984:
Use D_PARTISGPT rather than bare 255

These three cases dovetail with other places in the code where we use
or set D_PARTISGPT when we mean that the partitioning scheme is
GPT. Use this #define to make the code easier to undertand.

r348748:
loader: disk_open() should honor D_PARTNONE

The D_PARTNONE is documented to make it possible to open raw MBR
partition, but the current disk_open() does not really implement this
statement.

The current code is checking partition against -1 (D_PARTNONE) but does
attempt to open partition table in case we do have FreeBSD MBR partition
type.
Instead, we should check -2 (D_PARTWILD).

In case we do have MBR + BSD label, this code is only working because
by default, the first BSD partiton is created starting with relative sector
0, and we can still access the BSD table from that MBR slice.

PR:		236981