| Message ID | 20240118170628.3049797-10-ardb+git@google.com |
|---|---|
| Headers | show |
| Series | crypto: Clean up arm64 AES-CCM code | expand |
On Thu, Jan 18, 2024 at 06:06:29PM +0100, Ard Biesheuvel wrote: > From: Ard Biesheuvel <ardb@kernel.org> > > The AES-CCM driver was written 10+ years ago, based on the very first > kernel mode NEON API for arm64, which eagerly preserved/restored the > NEON registers on each call to kernel_neon_begin() resp. > kernel_neon_end(). > > For this reason, the asm helpers were constructed in a way that used > only 6 NEON registers, as the kernel mode NEON API at the time > implemented an optimization where kernel_neon_begin() took an int > denoting the number of NEON registers to preserve/restore. Given that no > actual hardware existed at the time (except perhaps for APM Xgene1 which > did not implement the crypto instructions), all of this was based on > premature assumptions. > > These days, the NEON API is a bit more sophisticated, and does not > bother to preserve/restore anything unless it is needed (e.g., when > context switching or returning to user space). It also no longer > disables preemption. Finally, we've developed some code patterns in the > mean time to deal with tail blocks more cleanly and efficiently. > > So let's bring the CCM driver up to date with all of this. > > Changes since v1: > - keep primary en/decryption paths separate > - fix rebase error in v1 > > Ard Biesheuvel (8): > crypto: arm64/aes-ccm - Revert "Rewrite skcipher walker loop" > crypto: arm64/aes-ccm - Keep NEON enabled during skcipher walk > crypto: arm64/aes-ccm - Pass short inputs via stack buffer > crypto: arm64/aes-ccm - Replace bytewise tail handling with NEON > permute > crypto: arm64/aes-ccm - Reuse existing MAC update for AAD input > crypto: arm64/aes-ccm - Cache round keys and unroll AES loops > crypto: arm64/aes-ccm - Merge encrypt and decrypt tail handling > crypto: arm64/aes-ccm - Merge finalization into en/decrypt asm helpers > > arch/arm64/crypto/Kconfig | 1 + > arch/arm64/crypto/aes-ce-ccm-core.S | 265 +++++++------------- > arch/arm64/crypto/aes-ce-ccm-glue.c | 154 ++++++++---- > arch/arm64/crypto/aes-glue.c | 1 + > 4 files changed, 200 insertions(+), 221 deletions(-) > > -- > 2.43.0.381.gb435a96ce8-goog All applied. Thanks.
From: Ard Biesheuvel <ardb@kernel.org> The AES-CCM driver was written 10+ years ago, based on the very first kernel mode NEON API for arm64, which eagerly preserved/restored the NEON registers on each call to kernel_neon_begin() resp. kernel_neon_end(). For this reason, the asm helpers were constructed in a way that used only 6 NEON registers, as the kernel mode NEON API at the time implemented an optimization where kernel_neon_begin() took an int denoting the number of NEON registers to preserve/restore. Given that no actual hardware existed at the time (except perhaps for APM Xgene1 which did not implement the crypto instructions), all of this was based on premature assumptions. These days, the NEON API is a bit more sophisticated, and does not bother to preserve/restore anything unless it is needed (e.g., when context switching or returning to user space). It also no longer disables preemption. Finally, we've developed some code patterns in the mean time to deal with tail blocks more cleanly and efficiently. So let's bring the CCM driver up to date with all of this. Changes since v1: - keep primary en/decryption paths separate - fix rebase error in v1 Ard Biesheuvel (8): crypto: arm64/aes-ccm - Revert "Rewrite skcipher walker loop" crypto: arm64/aes-ccm - Keep NEON enabled during skcipher walk crypto: arm64/aes-ccm - Pass short inputs via stack buffer crypto: arm64/aes-ccm - Replace bytewise tail handling with NEON permute crypto: arm64/aes-ccm - Reuse existing MAC update for AAD input crypto: arm64/aes-ccm - Cache round keys and unroll AES loops crypto: arm64/aes-ccm - Merge encrypt and decrypt tail handling crypto: arm64/aes-ccm - Merge finalization into en/decrypt asm helpers arch/arm64/crypto/Kconfig | 1 + arch/arm64/crypto/aes-ce-ccm-core.S | 265 +++++++------------- arch/arm64/crypto/aes-ce-ccm-glue.c | 154 ++++++++---- arch/arm64/crypto/aes-glue.c | 1 + 4 files changed, 200 insertions(+), 221 deletions(-)