From 7c9d65c40a53290039c701cacfd4316a699061a5 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Tue, 3 Sep 2019 09:43:32 -0700 Subject: [PATCH] crypto: arm64/aes-cts-cbc - move request context data to the stack Since the CTS-CBC code completes synchronously, there is no point in keeping part of the scratch data it uses in the request context, so move it to the stack instead. Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu --- arch/arm64/crypto/aes-glue.c | 61 +++++++++++++++--------------------- 1 file changed, 26 insertions(+), 35 deletions(-) diff --git a/arch/arm64/crypto/aes-glue.c b/arch/arm64/crypto/aes-glue.c index a1c4e30d76c9..e78f69b81dfc 100644 --- a/arch/arm64/crypto/aes-glue.c +++ b/arch/arm64/crypto/aes-glue.c @@ -107,12 +107,6 @@ asmlinkage void aes_mac_update(u8 const in[], u32 const rk[], int rounds, int blocks, u8 dg[], int enc_before, int enc_after); -struct cts_cbc_req_ctx { - struct scatterlist sg_src[2]; - struct scatterlist sg_dst[2]; - struct skcipher_request subreq; -}; - struct crypto_aes_xts_ctx { struct crypto_aes_ctx key1; struct crypto_aes_ctx __aligned(8) key2; @@ -292,23 +286,20 @@ static int __maybe_unused cbc_decrypt(struct skcipher_request *req) return cbc_decrypt_walk(req, &walk); } -static int cts_cbc_init_tfm(struct crypto_skcipher *tfm) -{ - crypto_skcipher_set_reqsize(tfm, sizeof(struct cts_cbc_req_ctx)); - return 0; -} - static int cts_cbc_encrypt(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); - struct cts_cbc_req_ctx *rctx = skcipher_request_ctx(req); int err, rounds = 6 + ctx->key_length / 4; int cbc_blocks = DIV_ROUND_UP(req->cryptlen, AES_BLOCK_SIZE) - 2; struct scatterlist *src = req->src, *dst = req->dst; + struct scatterlist sg_src[2], sg_dst[2]; + struct skcipher_request subreq; struct skcipher_walk walk; - skcipher_request_set_tfm(&rctx->subreq, tfm); + skcipher_request_set_tfm(&subreq, tfm); + skcipher_request_set_callback(&subreq, skcipher_request_flags(req), + NULL, NULL); if (req->cryptlen <= AES_BLOCK_SIZE) { if (req->cryptlen < AES_BLOCK_SIZE) @@ -317,31 +308,30 @@ static int cts_cbc_encrypt(struct skcipher_request *req) } if (cbc_blocks > 0) { - skcipher_request_set_crypt(&rctx->subreq, req->src, req->dst, + skcipher_request_set_crypt(&subreq, req->src, req->dst, cbc_blocks * AES_BLOCK_SIZE, req->iv); - err = skcipher_walk_virt(&walk, &rctx->subreq, false) ?: - cbc_encrypt_walk(&rctx->subreq, &walk); + err = skcipher_walk_virt(&walk, &subreq, false) ?: + cbc_encrypt_walk(&subreq, &walk); if (err) return err; if (req->cryptlen == AES_BLOCK_SIZE) return 0; - dst = src = scatterwalk_ffwd(rctx->sg_src, req->src, - rctx->subreq.cryptlen); + dst = src = scatterwalk_ffwd(sg_src, req->src, subreq.cryptlen); if (req->dst != req->src) - dst = scatterwalk_ffwd(rctx->sg_dst, req->dst, - rctx->subreq.cryptlen); + dst = scatterwalk_ffwd(sg_dst, req->dst, + subreq.cryptlen); } /* handle ciphertext stealing */ - skcipher_request_set_crypt(&rctx->subreq, src, dst, + skcipher_request_set_crypt(&subreq, src, dst, req->cryptlen - cbc_blocks * AES_BLOCK_SIZE, req->iv); - err = skcipher_walk_virt(&walk, &rctx->subreq, false); + err = skcipher_walk_virt(&walk, &subreq, false); if (err) return err; @@ -357,13 +347,16 @@ static int cts_cbc_decrypt(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); - struct cts_cbc_req_ctx *rctx = skcipher_request_ctx(req); int err, rounds = 6 + ctx->key_length / 4; int cbc_blocks = DIV_ROUND_UP(req->cryptlen, AES_BLOCK_SIZE) - 2; struct scatterlist *src = req->src, *dst = req->dst; + struct scatterlist sg_src[2], sg_dst[2]; + struct skcipher_request subreq; struct skcipher_walk walk; - skcipher_request_set_tfm(&rctx->subreq, tfm); + skcipher_request_set_tfm(&subreq, tfm); + skcipher_request_set_callback(&subreq, skcipher_request_flags(req), + NULL, NULL); if (req->cryptlen <= AES_BLOCK_SIZE) { if (req->cryptlen < AES_BLOCK_SIZE) @@ -372,31 +365,30 @@ static int cts_cbc_decrypt(struct skcipher_request *req) } if (cbc_blocks > 0) { - skcipher_request_set_crypt(&rctx->subreq, req->src, req->dst, + skcipher_request_set_crypt(&subreq, req->src, req->dst, cbc_blocks * AES_BLOCK_SIZE, req->iv); - err = skcipher_walk_virt(&walk, &rctx->subreq, false) ?: - cbc_decrypt_walk(&rctx->subreq, &walk); + err = skcipher_walk_virt(&walk, &subreq, false) ?: + cbc_decrypt_walk(&subreq, &walk); if (err) return err; if (req->cryptlen == AES_BLOCK_SIZE) return 0; - dst = src = scatterwalk_ffwd(rctx->sg_src, req->src, - rctx->subreq.cryptlen); + dst = src = scatterwalk_ffwd(sg_src, req->src, subreq.cryptlen); if (req->dst != req->src) - dst = scatterwalk_ffwd(rctx->sg_dst, req->dst, - rctx->subreq.cryptlen); + dst = scatterwalk_ffwd(sg_dst, req->dst, + subreq.cryptlen); } /* handle ciphertext stealing */ - skcipher_request_set_crypt(&rctx->subreq, src, dst, + skcipher_request_set_crypt(&subreq, src, dst, req->cryptlen - cbc_blocks * AES_BLOCK_SIZE, req->iv); - err = skcipher_walk_virt(&walk, &rctx->subreq, false); + err = skcipher_walk_virt(&walk, &subreq, false); if (err) return err; @@ -673,7 +665,6 @@ static struct skcipher_alg aes_algs[] = { { .setkey = skcipher_aes_setkey, .encrypt = cts_cbc_encrypt, .decrypt = cts_cbc_decrypt, - .init = cts_cbc_init_tfm, }, { .base = { .cra_name = "__essiv(cbc(aes),sha256)", -- 2.30.2