From 41c76690b0990efacd15d35cfb4e77318cd80ebb Mon Sep 17 00:00:00 2001 From: Nicolas Toromanoff Date: Tue, 30 Nov 2021 08:54:55 +0100 Subject: crypto: stm32/cryp - fix CTR counter carry STM32 CRYP hardware doesn't manage CTR counter bigger than max U32, as a workaround, at each block the current IV is saved, if the saved IV lower u32 is 0xFFFFFFFF, the full IV is manually incremented, and set in hardware. Fixes: bbb2832620ac ("crypto: stm32 - Fix sparse warnings") Signed-off-by: Nicolas Toromanoff Signed-off-by: Herbert Xu --- drivers/crypto/stm32/stm32-cryp.c | 27 +++++++++++++-------------- 1 file changed, 13 insertions(+), 14 deletions(-) (limited to 'drivers/crypto/stm32') diff --git a/drivers/crypto/stm32/stm32-cryp.c b/drivers/crypto/stm32/stm32-cryp.c index 7b55ad6d2f1a..ab4a107a0860 100644 --- a/drivers/crypto/stm32/stm32-cryp.c +++ b/drivers/crypto/stm32/stm32-cryp.c @@ -163,7 +163,7 @@ struct stm32_cryp { struct scatter_walk in_walk; struct scatter_walk out_walk; - u32 last_ctr[4]; + __be32 last_ctr[4]; u32 gcm_ctr; }; @@ -1217,27 +1217,26 @@ static void stm32_cryp_check_ctr_counter(struct stm32_cryp *cryp) { u32 cr; - if (unlikely(cryp->last_ctr[3] == 0xFFFFFFFF)) { - cryp->last_ctr[3] = 0; - cryp->last_ctr[2]++; - if (!cryp->last_ctr[2]) { - cryp->last_ctr[1]++; - if (!cryp->last_ctr[1]) - cryp->last_ctr[0]++; - } + if (unlikely(cryp->last_ctr[3] == cpu_to_be32(0xFFFFFFFF))) { + /* + * In this case, we need to increment manually the ctr counter, + * as HW doesn't handle the U32 carry. + */ + crypto_inc((u8 *)cryp->last_ctr, sizeof(cryp->last_ctr)); cr = stm32_cryp_read(cryp, CRYP_CR); stm32_cryp_write(cryp, CRYP_CR, cr & ~CR_CRYPEN); - stm32_cryp_hw_write_iv(cryp, (__be32 *)cryp->last_ctr); + stm32_cryp_hw_write_iv(cryp, cryp->last_ctr); stm32_cryp_write(cryp, CRYP_CR, cr); } - cryp->last_ctr[0] = stm32_cryp_read(cryp, CRYP_IV0LR); - cryp->last_ctr[1] = stm32_cryp_read(cryp, CRYP_IV0RR); - cryp->last_ctr[2] = stm32_cryp_read(cryp, CRYP_IV1LR); - cryp->last_ctr[3] = stm32_cryp_read(cryp, CRYP_IV1RR); + /* The IV registers are BE */ + cryp->last_ctr[0] = cpu_to_be32(stm32_cryp_read(cryp, CRYP_IV0LR)); + cryp->last_ctr[1] = cpu_to_be32(stm32_cryp_read(cryp, CRYP_IV0RR)); + cryp->last_ctr[2] = cpu_to_be32(stm32_cryp_read(cryp, CRYP_IV1LR)); + cryp->last_ctr[3] = cpu_to_be32(stm32_cryp_read(cryp, CRYP_IV1RR)); } static bool stm32_cryp_irq_read_data(struct stm32_cryp *cryp) -- cgit v1.2.3