diff options
Diffstat (limited to 'drivers/crypto/ccp/ccp-crypto-aes-xts.c')
| -rw-r--r-- | drivers/crypto/ccp/ccp-crypto-aes-xts.c | 96 |
1 files changed, 53 insertions, 43 deletions
diff --git a/drivers/crypto/ccp/ccp-crypto-aes-xts.c b/drivers/crypto/ccp/ccp-crypto-aes-xts.c index 58a4244b4752..94b5bcf5b628 100644 --- a/drivers/crypto/ccp/ccp-crypto-aes-xts.c +++ b/drivers/crypto/ccp/ccp-crypto-aes-xts.c @@ -1,8 +1,9 @@ /* * AMD Cryptographic Coprocessor (CCP) AES XTS crypto API support * - * Copyright (C) 2013 Advanced Micro Devices, Inc. + * Copyright (C) 2013,2017 Advanced Micro Devices, Inc. * + * Author: Gary R Hook <gary.hook@amd.com> * Author: Tom Lendacky <thomas.lendacky@amd.com> * * This program is free software; you can redistribute it and/or modify @@ -15,6 +16,7 @@ #include <linux/delay.h> #include <linux/scatterlist.h> #include <crypto/aes.h> +#include <crypto/xts.h> #include <crypto/internal/skcipher.h> #include <crypto/scatterwalk.h> @@ -37,46 +39,26 @@ struct ccp_unit_size_map { u32 value; }; -static struct ccp_unit_size_map unit_size_map[] = { +static struct ccp_unit_size_map xts_unit_sizes[] = { { - .size = 4096, - .value = CCP_XTS_AES_UNIT_SIZE_4096, - }, - { - .size = 2048, - .value = CCP_XTS_AES_UNIT_SIZE_2048, - }, - { - .size = 1024, - .value = CCP_XTS_AES_UNIT_SIZE_1024, + .size = 16, + .value = CCP_XTS_AES_UNIT_SIZE_16, }, { - .size = 512, + .size = 512, .value = CCP_XTS_AES_UNIT_SIZE_512, }, { - .size = 256, - .value = CCP_XTS_AES_UNIT_SIZE__LAST, - }, - { - .size = 128, - .value = CCP_XTS_AES_UNIT_SIZE__LAST, - }, - { - .size = 64, - .value = CCP_XTS_AES_UNIT_SIZE__LAST, - }, - { - .size = 32, - .value = CCP_XTS_AES_UNIT_SIZE__LAST, + .size = 1024, + .value = CCP_XTS_AES_UNIT_SIZE_1024, }, { - .size = 16, - .value = CCP_XTS_AES_UNIT_SIZE_16, + .size = 2048, + .value = CCP_XTS_AES_UNIT_SIZE_2048, }, { - .size = 1, - .value = CCP_XTS_AES_UNIT_SIZE__LAST, + .size = 4096, + .value = CCP_XTS_AES_UNIT_SIZE_4096, }, }; @@ -96,15 +78,26 @@ static int ccp_aes_xts_complete(struct crypto_async_request *async_req, int ret) static int ccp_aes_xts_setkey(struct crypto_ablkcipher *tfm, const u8 *key, unsigned int key_len) { - struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ablkcipher_tfm(tfm)); + struct crypto_tfm *xfm = crypto_ablkcipher_tfm(tfm); + struct ccp_ctx *ctx = crypto_tfm_ctx(xfm); + unsigned int ccpversion = ccp_version(); + int ret; - /* Only support 128-bit AES key with a 128-bit Tweak key, - * otherwise use the fallback + ret = xts_check_key(xfm, key, key_len); + if (ret) + return ret; + + /* Version 3 devices support 128-bit keys; version 5 devices can + * accommodate 128- and 256-bit keys. */ switch (key_len) { case AES_KEYSIZE_128 * 2: memcpy(ctx->u.aes.key, key, key_len); break; + case AES_KEYSIZE_256 * 2: + if (ccpversion > CCP_VERSION(3, 0)) + memcpy(ctx->u.aes.key, key, key_len); + break; } ctx->u.aes.key_len = key_len / 2; sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len); @@ -117,6 +110,8 @@ static int ccp_aes_xts_crypt(struct ablkcipher_request *req, { struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm); struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req); + unsigned int ccpversion = ccp_version(); + unsigned int fallback = 0; unsigned int unit; u32 unit_size; int ret; @@ -130,18 +125,32 @@ static int ccp_aes_xts_crypt(struct ablkcipher_request *req, if (!req->info) return -EINVAL; + /* Check conditions under which the CCP can fulfill a request. The + * device can handle input plaintext of a length that is a multiple + * of the unit_size, bug the crypto implementation only supports + * the unit_size being equal to the input length. This limits the + * number of scenarios we can handle. + */ unit_size = CCP_XTS_AES_UNIT_SIZE__LAST; - if (req->nbytes <= unit_size_map[0].size) { - for (unit = 0; unit < ARRAY_SIZE(unit_size_map); unit++) { - if (!(req->nbytes & (unit_size_map[unit].size - 1))) { - unit_size = unit_size_map[unit].value; - break; - } + for (unit = 0; unit < ARRAY_SIZE(xts_unit_sizes); unit++) { + if (req->nbytes == xts_unit_sizes[unit].size) { + unit_size = unit; + break; } } - - if ((unit_size == CCP_XTS_AES_UNIT_SIZE__LAST) || - (ctx->u.aes.key_len != AES_KEYSIZE_128)) { + /* The CCP has restrictions on block sizes. Also, a version 3 device + * only supports AES-128 operations; version 5 CCPs support both + * AES-128 and -256 operations. + */ + if (unit_size == CCP_XTS_AES_UNIT_SIZE__LAST) + fallback = 1; + if ((ccpversion < CCP_VERSION(5, 0)) && + (ctx->u.aes.key_len != AES_KEYSIZE_128)) + fallback = 1; + if ((ctx->u.aes.key_len != AES_KEYSIZE_128) && + (ctx->u.aes.key_len != AES_KEYSIZE_256)) + fallback = 1; + if (fallback) { SKCIPHER_REQUEST_ON_STACK(subreq, ctx->u.aes.tfm_skcipher); /* Use the fallback to process the request for any @@ -164,6 +173,7 @@ static int ccp_aes_xts_crypt(struct ablkcipher_request *req, memset(&rctx->cmd, 0, sizeof(rctx->cmd)); INIT_LIST_HEAD(&rctx->cmd.entry); rctx->cmd.engine = CCP_ENGINE_XTS_AES_128; + rctx->cmd.u.xts.type = CCP_AES_TYPE_128; rctx->cmd.u.xts.action = (encrypt) ? CCP_AES_ACTION_ENCRYPT : CCP_AES_ACTION_DECRYPT; rctx->cmd.u.xts.unit_size = unit_size; |