From e9440ff37254c85cbc1143991a39b656957394ba Mon Sep 17 00:00:00 2001 From: Tudor-Dan Ambarus Date: Wed, 13 Jun 2018 16:29:58 +0300 Subject: [PATCH] crypto: atmel-ecc - fix to allow multi segment scatterlists Remove the limitation of single element scatterlists. ECDH with multi-element scatterlists is needed by TPM. Similar to 'commit 95ec01ba1ef0 ("crypto: ecdh - fix to allow multi segment scatterlists")'. Signed-off-by: Tudor Ambarus Signed-off-by: Herbert Xu --- drivers/crypto/atmel-ecc.c | 31 ++++++++++++++++++++++--------- 1 file changed, 22 insertions(+), 9 deletions(-) diff --git a/drivers/crypto/atmel-ecc.c b/drivers/crypto/atmel-ecc.c index e66f18a0ddd0..a25772ed26e1 100644 --- a/drivers/crypto/atmel-ecc.c +++ b/drivers/crypto/atmel-ecc.c @@ -186,7 +186,10 @@ static int atmel_ecc_init_ecdh_cmd(struct atmel_ecc_cmd *cmd, * always be the same. Use a macro for the key size to avoid unnecessary * computations. */ - copied = sg_copy_to_buffer(pubkey, 1, cmd->data, ATMEL_ECC_PUBKEY_SIZE); + copied = sg_copy_to_buffer(pubkey, + sg_nents_for_len(pubkey, + ATMEL_ECC_PUBKEY_SIZE), + cmd->data, ATMEL_ECC_PUBKEY_SIZE); if (copied != ATMEL_ECC_PUBKEY_SIZE) return -EINVAL; @@ -268,15 +271,17 @@ static void atmel_ecdh_done(struct atmel_ecc_work_data *work_data, void *areq, struct kpp_request *req = areq; struct atmel_ecdh_ctx *ctx = work_data->ctx; struct atmel_ecc_cmd *cmd = &work_data->cmd; - size_t copied; - size_t n_sz = ctx->n_sz; + size_t copied, n_sz; if (status) goto free_work_data; + /* might want less than we've got */ + n_sz = min_t(size_t, ctx->n_sz, req->dst_len); + /* copy the shared secret */ - copied = sg_copy_from_buffer(req->dst, 1, &cmd->data[RSP_DATA_IDX], - n_sz); + copied = sg_copy_from_buffer(req->dst, sg_nents_for_len(req->dst, n_sz), + &cmd->data[RSP_DATA_IDX], n_sz); if (copied != n_sz) status = -EINVAL; @@ -440,7 +445,7 @@ static int atmel_ecdh_generate_public_key(struct kpp_request *req) { struct crypto_kpp *tfm = crypto_kpp_reqtfm(req); struct atmel_ecdh_ctx *ctx = kpp_tfm_ctx(tfm); - size_t copied; + size_t copied, nbytes; int ret = 0; if (ctx->do_fallback) { @@ -448,10 +453,14 @@ static int atmel_ecdh_generate_public_key(struct kpp_request *req) return crypto_kpp_generate_public_key(req); } + /* might want less than we've got */ + nbytes = min_t(size_t, ATMEL_ECC_PUBKEY_SIZE, req->dst_len); + /* public key was saved at private key generation */ - copied = sg_copy_from_buffer(req->dst, 1, ctx->public_key, - ATMEL_ECC_PUBKEY_SIZE); - if (copied != ATMEL_ECC_PUBKEY_SIZE) + copied = sg_copy_from_buffer(req->dst, + sg_nents_for_len(req->dst, nbytes), + ctx->public_key, nbytes); + if (copied != nbytes) ret = -EINVAL; return ret; @@ -470,6 +479,10 @@ static int atmel_ecdh_compute_shared_secret(struct kpp_request *req) return crypto_kpp_compute_shared_secret(req); } + /* must have exactly two points to be on the curve */ + if (req->src_len != ATMEL_ECC_PUBKEY_SIZE) + return -EINVAL; + gfp = (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ? GFP_KERNEL : GFP_ATOMIC; -- 2.11.0