From 898387e40cf538b7d1605e05d456699fe418a77f Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 27 Aug 2021 09:03:42 +0200 Subject: crypto: arm64/aes-ccm - avoid by-ref argument for ce_aes_ccm_auth_data With the SIMD code path removed, we can clean up the CCM auth-only path a bit further, by passing the 'macp' input buffer pointer by value, rather than by reference, and taking the output value from the function's return value. This way, the compiler is no longer forced to allocate macp on the stack. This is not expected to make any difference in practice, it just makes for slightly cleaner code. Signed-off-by: Ard Biesheuvel Reviewed-by: Eric Biggers Signed-off-by: Herbert Xu --- arch/arm64/crypto/aes-ce-ccm-core.S | 23 +++++++++++------------ 1 file changed, 11 insertions(+), 12 deletions(-) (limited to 'arch/arm64/crypto/aes-ce-ccm-core.S') diff --git a/arch/arm64/crypto/aes-ce-ccm-core.S b/arch/arm64/crypto/aes-ce-ccm-core.S index 8adff299fcd3..b03f7f71f893 100644 --- a/arch/arm64/crypto/aes-ce-ccm-core.S +++ b/arch/arm64/crypto/aes-ce-ccm-core.S @@ -12,22 +12,21 @@ .arch armv8-a+crypto /* - * void ce_aes_ccm_auth_data(u8 mac[], u8 const in[], u32 abytes, - * u32 *macp, u8 const rk[], u32 rounds); + * u32 ce_aes_ccm_auth_data(u8 mac[], u8 const in[], u32 abytes, + * u32 macp, u8 const rk[], u32 rounds); */ SYM_FUNC_START(ce_aes_ccm_auth_data) - ldr w8, [x3] /* leftover from prev round? */ ld1 {v0.16b}, [x0] /* load mac */ - cbz w8, 1f - sub w8, w8, #16 + cbz w3, 1f + sub w3, w3, #16 eor v1.16b, v1.16b, v1.16b 0: ldrb w7, [x1], #1 /* get 1 byte of input */ subs w2, w2, #1 - add w8, w8, #1 + add w3, w3, #1 ins v1.b[0], w7 ext v1.16b, v1.16b, v1.16b, #1 /* rotate in the input bytes */ beq 8f /* out of input? */ - cbnz w8, 0b + cbnz w3, 0b eor v0.16b, v0.16b, v1.16b 1: ld1 {v3.4s}, [x4] /* load first round key */ prfm pldl1strm, [x1] @@ -62,7 +61,7 @@ SYM_FUNC_START(ce_aes_ccm_auth_data) beq 10f adds w2, w2, #16 beq 10f - mov w8, w2 + mov w3, w2 7: ldrb w7, [x1], #1 umov w6, v0.b[0] eor w6, w6, w7 @@ -71,15 +70,15 @@ SYM_FUNC_START(ce_aes_ccm_auth_data) beq 10f ext v0.16b, v0.16b, v0.16b, #1 /* rotate out the mac bytes */ b 7b -8: cbz w8, 91f - mov w7, w8 - add w8, w8, #16 +8: cbz w3, 91f + mov w7, w3 + add w3, w3, #16 9: ext v1.16b, v1.16b, v1.16b, #1 adds w7, w7, #1 bne 9b 91: eor v0.16b, v0.16b, v1.16b st1 {v0.16b}, [x0] -10: str w8, [x3] +10: mov w0, w3 ret SYM_FUNC_END(ce_aes_ccm_auth_data) -- cgit v1.2.3-59-g8ed1b