From 61b0dd664fa1873501297efbb12e5684aff074d4 Mon Sep 17 00:00:00 2001 From: Tudor Ambarus Date: Fri, 15 Nov 2019 13:49:06 +0000 Subject: crypto: atmel-tdes - Set the IV after {en,de}crypt The req->iv of the skcipher_request is expected to contain the last ciphertext block when the {en,de}crypt operation is done. In case of in-place decryption, copy the ciphertext in an intermediate buffer before decryption. This fixes the following tcrypt tests: alg: skcipher: atmel-cbc-des encryption test failed (wrong output IV) on test vector 0, cfg="in-place" 00000000: fe dc ba 98 76 54 32 10 alg: skcipher: atmel-cbc-tdes encryption test failed (wrong output IV) on test vector 0, cfg="in-place" 00000000: 7d 33 88 93 0f 93 b2 42 Signed-off-by: Tudor Ambarus Signed-off-by: Herbert Xu --- drivers/crypto/atmel-tdes.c | 40 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 38 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/crypto/atmel-tdes.c b/drivers/crypto/atmel-tdes.c index bb7c0a387c04..0c1f79b30fc1 100644 --- a/drivers/crypto/atmel-tdes.c +++ b/drivers/crypto/atmel-tdes.c @@ -81,6 +81,7 @@ struct atmel_tdes_ctx { struct atmel_tdes_reqctx { unsigned long mode; + u8 lastc[DES_BLOCK_SIZE]; }; struct atmel_tdes_dma { @@ -572,6 +573,30 @@ static int atmel_tdes_crypt_start(struct atmel_tdes_dev *dd) return err; } +static void +atmel_tdes_set_iv_as_last_ciphertext_block(struct atmel_tdes_dev *dd) +{ + struct skcipher_request *req = dd->req; + struct atmel_tdes_reqctx *rctx = skcipher_request_ctx(req); + struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req); + unsigned int ivsize = crypto_skcipher_ivsize(skcipher); + + if (req->cryptlen < ivsize) + return; + + if (rctx->mode & TDES_FLAGS_ENCRYPT) { + scatterwalk_map_and_copy(req->iv, req->dst, + req->cryptlen - ivsize, ivsize, 0); + } else { + if (req->src == req->dst) + memcpy(req->iv, rctx->lastc, ivsize); + else + scatterwalk_map_and_copy(req->iv, req->src, + req->cryptlen - ivsize, + ivsize, 0); + } +} + static void atmel_tdes_finish_req(struct atmel_tdes_dev *dd, int err) { struct skcipher_request *req = dd->req; @@ -580,6 +605,8 @@ static void atmel_tdes_finish_req(struct atmel_tdes_dev *dd, int err) dd->flags &= ~TDES_FLAGS_BUSY; + atmel_tdes_set_iv_as_last_ciphertext_block(dd); + req->base.complete(&req->base, err); } @@ -668,8 +695,8 @@ static int atmel_tdes_crypt_dma_stop(struct atmel_tdes_dev *dd) static int atmel_tdes_crypt(struct skcipher_request *req, unsigned long mode) { - struct atmel_tdes_ctx *ctx = crypto_skcipher_ctx( - crypto_skcipher_reqtfm(req)); + struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req); + struct atmel_tdes_ctx *ctx = crypto_skcipher_ctx(skcipher); struct atmel_tdes_reqctx *rctx = skcipher_request_ctx(req); if (mode & TDES_FLAGS_CFB8) { @@ -700,6 +727,15 @@ static int atmel_tdes_crypt(struct skcipher_request *req, unsigned long mode) rctx->mode = mode; + if (!(mode & TDES_FLAGS_ENCRYPT) && req->src == req->dst) { + unsigned int ivsize = crypto_skcipher_ivsize(skcipher); + + if (req->cryptlen >= ivsize) + scatterwalk_map_and_copy(rctx->lastc, req->src, + req->cryptlen - ivsize, + ivsize, 0); + } + return atmel_tdes_handle_queue(ctx->dd, req); } -- cgit v1.2.3-59-g8ed1b