crypto: arm64/aes-neonbs - fix crash with CFI enabled

aesbs_ecb_encrypt(), aesbs_ecb_decrypt(), aesbs_xts_encrypt(), and
aesbs_xts_decrypt() are called via indirect function calls. Therefore
they need to use SYM_TYPED_FUNC_START instead of SYM_FUNC_START to cause
their type hashes to be emitted when the kernel is built with
CONFIG_CFI_CLANG=y. Otherwise, the code crashes with a CFI failure if
the compiler doesn't happen to optimize out the indirect calls.

Fixes: c50d32859e70 ("arm64: Add types to indirect called assembly functions")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: arm64/aes-neonbs - use frame_push/pop consistently

Use the frame_push and frame_pop macros consistently to create the stack
frame, so that we will get PAC and/or shadow call stack handling as well
when enabled.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: arm64/aes-neonbs-xts - use plain NEON for non-power-of-2 input sizes

Even though the kernel's implementations of AES-XTS were updated to
implement ciphertext stealing and can operate on inputs of any size
larger than or equal to the AES block size, this feature is rarely used
in practice.

In fact, in the kernel, AES-XTS is only used to operate on 4096 or 512
byte blocks, which means that not only the ciphertext stealing is
effectively dead code, the logic in the bit sliced NEON implementation
to deal with fewer than 8 blocks at a time is also never used.

Since the bit-sliced NEON driver already depends on the plain NEON
version, which is slower but can operate on smaller data quantities more
straightforwardly, let's fallback to the plain NEON implementation of
XTS for any residual inputs that are not multiples of 128 bytes. This
allows us to remove a lot of complicated logic that rarely gets
exercised in practice.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: arm64/aes-neonbs-ctr - fallback to plain NEON for final chunk

Instead of processing the entire input with the 8-way bit sliced
algorithm, which is sub-optimal for inputs that are not a multiple of
128 bytes in size, invoke the plain NEON version of CTR for the
remainder of the input after processing the bulk using 128 byte strides.

This allows us to greatly simplify the asm code that implements CTR, and
get rid of all the branches and special code paths. It also gains us a
couple of percent of performance.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: arm64/aes-neonbs - remove NEON yield calls

There is no need for elaborate yield handling in the bit-sliced NEON
implementation of AES, given that skciphers are naturally bounded by the
size of the chunks returned by the skcipher_walk API. So remove the
yield calls from the asm code.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: arm64: Use x16 with indirect branch to bti_c

The AES code uses a 'br x7' as part of a function called by
a macro. That branch needs a bti_j as a target. This results
in a panic as seen below. Using x16 (or x17) with an indirect
branch keeps the target bti_c.

Bad mode in Synchronous Abort handler detected on CPU1, code 0x34000003 -- BTI
CPU: 1 PID: 265 Comm: cryptomgr_test Not tainted 5.8.11-300.fc33.aarch64 #1
pstate: 20400c05 (nzCv daif +PAN -UAO BTYPE=j-)
pc : aesbs_encrypt8+0x0/0x5f0 [aes_neon_bs]
lr : aesbs_xts_encrypt+0x48/0xe0 [aes_neon_bs]
sp : ffff80001052b730

aesbs_encrypt8+0x0/0x5f0 [aes_neon_bs]
__xts_crypt+0xb0/0x2dc [aes_neon_bs]
xts_encrypt+0x28/0x3c [aes_neon_bs]
crypto_skcipher_encrypt+0x50/0x84
simd_skcipher_encrypt+0xc8/0xe0
crypto_skcipher_encrypt+0x50/0x84
test_skcipher_vec_cfg+0x224/0x5f0
test_skcipher+0xbc/0x120
alg_test_skcipher+0xa0/0x1b0
alg_test+0x3dc/0x47c
cryptomgr_test+0x38/0x60

Fixes: 0e89640b640d ("crypto: arm64 - Use modern annotations for assembly functions")
Cc: <stable@vger.kernel.org> # 5.6.x-
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Suggested-by: Dave P Martin <Dave.Martin@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20201006163326.2780619-1-jeremy.linton@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

crypto: arm64 - Use modern annotations for assembly functions

In an effort to clarify and simplify the annotation of assembly functions
in the kernel new macros have been introduced. These replace ENTRY and
ENDPROC and also add a new annotation for static functions which previously
had no ENTRY equivalent. Update the annotations in the crypto code to the
new macros.

There are a small number of files imported from OpenSSL where the assembly
is generated using perl programs, these are not currently annotated at all
and have not been modified.

Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: arm64/aes-neonbs - replace tweak mask literal with composition

Replace the vector load from memory sequence with a simple instruction
sequence to compose the tweak vector directly.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

crypto: arm64/aes-neonbs - fix returning final keystream block

The arm64 NEON bit-sliced implementation of AES-CTR fails the improved
skcipher tests because it sometimes produces the wrong ciphertext. The
bug is that the final keystream block isn't returned from the assembly
code when the number of non-final blocks is zero. This can happen if
the input data ends a few bytes after a page boundary. In this case the
last bytes get "encrypted" by XOR'ing them with uninitialized memory.

Fix the assembly code to return the final keystream block when needed.

Fixes: 88a3f582bea9 ("crypto: arm64/aes - don't use IV buffer to return final keystream block")
Cc: <stable@vger.kernel.org> # v4.11+
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: arm64/aes-bs - yield NEON after every block of input

Avoid excessive scheduling delays under a preemptible kernel by
yielding the NEON after every block of input.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: arm64/aes - don't use IV buffer to return final keystream block

The arm64 bit sliced AES core code uses the IV buffer to pass the final
keystream block back to the glue code if the input is not a multiple of
the block size, so that the asm code does not have to deal with anything
except 16 byte blocks. This is done under the assumption that the outgoing
IV is meaningless anyway in this case, given that chaining is no longer
possible under these circumstances.

However, as it turns out, the CCM driver does expect the IV to retain
a value that is equal to the original IV except for the counter value,
and even interprets byte zero as a length indicator, which may result
in memory corruption if the IV is overwritten with something else.

So use a separate buffer to return the final keystream block.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: arm64/aes - reimplement bit-sliced ARM/NEON implementation for arm64

This is a reimplementation of the NEON version of the bit-sliced AES
algorithm. This code is heavily based on Andy Polyakov's OpenSSL version
for ARM, which is also available in the kernel. This is an alternative for
the existing NEON implementation for arm64 authored by me, which suffers
from poor performance due to its reliance on the pathologically slow four
register variant of the tbl/tbx NEON instruction.

This version is about ~30% (*) faster than the generic C code, but only in
cases where the input can be 8x interleaved (this is a fundamental property
of bit slicing). For this reason, only the chaining modes ECB, XTS and CTR
are implemented. (The significance of ECB is that it could potentially be
used by other chaining modes)

* Measured on Cortex-A57. Note that this is still an order of magnitude
slower than the implementations that use the dedicated AES instructions
introduced in ARMv8, but those are part of an optional extension, and so
it is good to have a fallback.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>