sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

elf: EF_ARM_EABI_VERSION_UNKNOWN is no longer used, retire

EF_ARM_EABI_VERSION_UNKNOWN was used when we could run either eabi or
oabi. That was armv[45] only, and went away when we migrated to eabi
many major releases ago. No standard defines this symbol, so retire it.

Pointed out by: jrtc27
Sponsored by: Netflix

elf: Catch up with defining EF_ARM_EABI_VERSION in elf_common.h

FreeBSD defines EF_ARM_EABI_VERSION in a non-standard way (at least
differently than everybody else). We use this only in elf*machdep.c to
make sure the image is new enough. Switch to the more standard way of
defining this and adjust other constants to match.

Fixes: c52c98e69a2e
Sponsored by: Netflix

arm, arm64: tweak hard-coded load addresses for PIE binaries

They are used when ASLR is not applied.
The need for adjusting is due to rtld direct exec mode puts ld-elf.so.1
at the PIE load address, and this address must not conflict with the
default linker' load address for non-PIE binaries. Otherwise rtld in
direct mode cannot activate image. Example of implicit failure is ldd(1)
refusing to run.

Reported by: kp
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D37085

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

Remove remnant of arm's ELF trampoline

The trampoline code used for loading gzipped a.out kernels on arm was
removed in r350436. A portion of this code allowed for DDB to find the
symbol tables when booting without loader(8), and some of this was
untouched in the removal. Remove it now.

Differential Revision: https://reviews.freebsd.org/D24950

Move the fixed base for PIE loading on arm.

Existing base causes conflicts for direct execution of ld-elf.so.1
because default linking base for non-PIE binaries is 0x10000.

Reported and tested by: Mark Millard <marklmi26-fbsd@yahoo.com>
Sponsored by: The FreeBSD Foundation
MFC after: 1 week

Consolidate identical ELF auxargs type defintions.

All platforms except powerpc use the same values and powerpc shares a
majority of them.

Go ahead and declare AT_NOTELF, AT_UID, and AT_EUID in favor of the
unused AT_DCACHEBSIZE, AT_ICACHEBSIZE, and AT_UCACHEBSIZE for powerpc.

Reviewed by: jhb, imp
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D17397

sys/arm: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Fullify implementation of AT_HWCAP and AT_HWCAP2 for ARMv6,7.
This makes elf_aux_info(3) useable for ARM ports.

MFC after: 1 month

Add AT_HWCAP2 ELF auxiliary vector.
- allocate value for new AT_HWCAP2 auxiliary vector on all platforms.
- expand 'struct sysentvec' by new 'u_long *sv_hwcap2', in exactly
same way as for AT_HWCAP.

MFC after: 1 month
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D12699

Detect NEON and set HWCAP_NEON if present.

Reviewed by: andrew, ian
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D12389

Correct HWCAP_VFP3* values to match Linux.

Reviewed by: andrew, ian
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D12388

Add AT_HWCAP flags for VFP settings for FreeBSD/arm.

These flags match the meaning and value of flags in Linux, though
Linux has many more flags.

Reviewed by: stevek, Michal Meloun <meloun-miracle-cz> (earlier version)
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D12291

Add AT_HWCAP and AT_EHDRFLAGS on all platforms.

A new 'u_long *sv_hwcap' field is added to 'struct sysentvec'. A
process ABI can set this field to point to a value holding a mask of
architecture-specific CPU feature flags. If an ABI does not wish to
supply AT_HWCAP to processes the field can be left as NULL.

The support code for AT_EHDRFLAGS was already present on all systems,
just the #define was not present. This is a step towards unifying the
AT_* constants across platforms.

Reviewed by: kib
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D12290

Move/add ARM ELF PHDR types to elf_common.h

Accidentally missed in r303674

Export the eflags field from the elf header. This allows better
discrimination between different subarch binaries, at least for mips
and arm. Arm is implemented, mips is still tbd, so not currently
exported. aarch64 does not export this because aarch64 binaries use
different tags and flags than arm.

Differential Revision: https://reviews.freebsd.org/D2611

Update ELF headers to include additional defines

The elftoolchain project includes these additional defines for various
userland programs. Given that arch-specific defines are still interesting
in the context of userland programs reading or writing ELF metadata, they
should be included in top-level ELF headers.

Remove duplicate defines from ARM and MIPS elf headers.

Submitted by: will (initial version)
Reviewed by: imp, will
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D844

Expand the elf brandelf infrastructure to give access to the whole ELF
header (Elf_Ehdr) to determine if a particular interpretor wants to
accept it or not. Use this mechanism to filter EABI arm on OABI arm
kernels, and vice versa. This method could also be used to implement
OABI on EABI arm kernels, if desired, or to allow a single mips kernel
to run o32, n32 and n64 binaries.

Differential Revision: https://reviews.freebsd.org/D609

Add dl_unwind_find_exidx() for ARM EABI, required for C++ exception
handling. For statically linked apps this uses the __exidx_start/end
symbols set up by the linker. For dynamically linked apps it finds the
shared object that contains the given address and returns the location and
size of the exidx section in that shared object.

The dl_unwind_find_exidx() name is used by other BSD projects and Android,
and is mentioned in clang 3.5 comments as "the BSD interface" for finding
exidx data. GCC (in libgcc_s) expects the exact same API and functionality
to be provided by a function named __gnu_Unwind_Find_exidx(), so we provide
that with an alias ("strong reference").

Reviewed by: kib@
MFC after: 1 week

Reserve AT_TIMEKEEP auxv entry for providing usermode the pointer to
timekeeping information.

MFC after: 1 week

trim trailing whitespace

Add AT_STACKPROT elf aux vector. Will be used to inform rtld about the
initial stack protection set by the kernel image activator.

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Supply some useful information to the started image using ELF aux vectors.
In particular, provide pagesize and pagesizes array, the canary value
for SSP use, number of host CPUs and osreldate.

Tested by: marius (sparc64)
MFC after: 1 month

MFC r197933:
Define architectural load bases for PIE binaries.

MFC r198203 (by marius):
Change load base for sparc to match default gcc memory layout model.

Approved by: re (kensmith)

Define architectural load bases for PIE binaries. Addresses were selected
by looking at the bases used for non-relocatable executables by gnu ld(1),
and adjusting it slightly.

Discussed with: bz
Reviewed by: kan
Tested by: bz (i386, amd64), bsam (linux)
MFC after: some time

Add AT_EXECPATH ELF auxinfo entry type. The value's a_ptr is a pointer
to the full path of the image that is being executed.
Increase AT_COUNT.

Remove no longer true comment about types used in Linux ELF binaries,
listed types contain FreeBSD-specific entries.

Reviewed by: kan

AT_DEBUG and AT_BRK were OBE like 10 years ago, so retire them.

Reviewed by: peter

- Import the HEAD csup code which is the basis for the cvsmode work.

PR:
Submitted by:
Reviewed by:
Approved by:
Obtained from:
MFC after:
Security:
Move the relocation definitions to the common elf header so that DTrace
can use them on one architecture targeted to a different one.

Add the additional ELF types defines in Sun's "Linker and Libraries"
manual.

Use ELFDATA2MSB if we're building big endian.

Noticed by: Oleksandr Tymoshenko <gonzo freebsd org>

Use a magic number to know we were started from the elf wrapper.
Add a dummy _start function to make the non-elf version of the wrapper work.

Add the Elf32_Auxinfo declaretion.
Define AT_*.
(Maybe some of this could go in a MI header ?)

Add sysentvec->sv_fixlimits() hook so that we can catch cases on 64 bit
systems where the data/stack/etc limits are too big for a 32 bit process.

Move the 5 or so identical instances of ELF_RTLD_ADDR() into imgact_elf.c.

Supply an ia32_fixlimits function. Export the clip/default values to
sysctl under the compat.ia32 heirarchy.

Have mmap(0, ...) respect the current p->p_limits[RLIMIT_DATA].rlim_max
value rather than the sysctl tweakable variable. This allows mmap to
place mappings at sensible locations when limits have been reduced.

Have the imgact_elf.c ld-elf.so.1 placement algorithm use the same
method as mmap(0, ...) now does.

Note that we cannot remove all references to the sysctl tweakable
maxdsiz etc variables because /etc/login.conf specifies a datasize
of 'unlimited'. And that causes exec etc to fail since it can no
longer find space to mmap things.

Make MAXTSIZ, DFLDSIZ, MAXDSIZ, DFLSSIZ, MAXSSIZ, SGROWSIZ loader
tunable.

Reviewed by: peter
MFC after: 2 weeks

Fix style of defines.

StrongARM platform-specific definitions.