diff options
Diffstat (limited to 'drivers/crypto/xilinx/zynqmp-aes-gcm.c')
| -rw-r--r-- | drivers/crypto/xilinx/zynqmp-aes-gcm.c | 449 |
1 files changed, 449 insertions, 0 deletions
diff --git a/drivers/crypto/xilinx/zynqmp-aes-gcm.c b/drivers/crypto/xilinx/zynqmp-aes-gcm.c new file mode 100644 index 000000000..bf1f421e0 --- /dev/null +++ b/drivers/crypto/xilinx/zynqmp-aes-gcm.c @@ -0,0 +1,449 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Xilinx ZynqMP AES Driver. + * Copyright (c) 2020 Xilinx Inc. + */ + +#include <crypto/aes.h> +#include <crypto/engine.h> +#include <crypto/gcm.h> +#include <crypto/internal/aead.h> +#include <crypto/scatterwalk.h> + +#include <linux/dma-mapping.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> + +#include <linux/firmware/xlnx-zynqmp.h> + +#define ZYNQMP_DMA_BIT_MASK 32U + +#define ZYNQMP_AES_KEY_SIZE AES_KEYSIZE_256 +#define ZYNQMP_AES_AUTH_SIZE 16U +#define ZYNQMP_KEY_SRC_SEL_KEY_LEN 1U +#define ZYNQMP_AES_BLK_SIZE 1U +#define ZYNQMP_AES_MIN_INPUT_BLK_SIZE 4U +#define ZYNQMP_AES_WORD_LEN 4U + +#define ZYNQMP_AES_GCM_TAG_MISMATCH_ERR 0x01 +#define ZYNQMP_AES_WRONG_KEY_SRC_ERR 0x13 +#define ZYNQMP_AES_PUF_NOT_PROGRAMMED 0xE300 + +enum zynqmp_aead_op { + ZYNQMP_AES_DECRYPT = 0, + ZYNQMP_AES_ENCRYPT +}; + +enum zynqmp_aead_keysrc { + ZYNQMP_AES_KUP_KEY = 0, + ZYNQMP_AES_DEV_KEY, + ZYNQMP_AES_PUF_KEY +}; + +struct zynqmp_aead_drv_ctx { + union { + struct aead_alg aead; + } alg; + struct device *dev; + struct crypto_engine *engine; +}; + +struct zynqmp_aead_hw_req { + u64 src; + u64 iv; + u64 key; + u64 dst; + u64 size; + u64 op; + u64 keysrc; +}; + +struct zynqmp_aead_tfm_ctx { + struct crypto_engine_ctx engine_ctx; + struct device *dev; + u8 key[ZYNQMP_AES_KEY_SIZE]; + u8 *iv; + u32 keylen; + u32 authsize; + enum zynqmp_aead_keysrc keysrc; + struct crypto_aead *fbk_cipher; +}; + +struct zynqmp_aead_req_ctx { + enum zynqmp_aead_op op; +}; + +static int zynqmp_aes_aead_cipher(struct aead_request *req) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct zynqmp_aead_tfm_ctx *tfm_ctx = crypto_aead_ctx(aead); + struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req); + struct device *dev = tfm_ctx->dev; + struct zynqmp_aead_hw_req *hwreq; + dma_addr_t dma_addr_data, dma_addr_hw_req; + unsigned int data_size; + unsigned int status; + int ret; + size_t dma_size; + char *kbuf; + int err; + + if (tfm_ctx->keysrc == ZYNQMP_AES_KUP_KEY) + dma_size = req->cryptlen + ZYNQMP_AES_KEY_SIZE + + GCM_AES_IV_SIZE; + else + dma_size = req->cryptlen + GCM_AES_IV_SIZE; + + kbuf = dma_alloc_coherent(dev, dma_size, &dma_addr_data, GFP_KERNEL); + if (!kbuf) + return -ENOMEM; + + hwreq = dma_alloc_coherent(dev, sizeof(struct zynqmp_aead_hw_req), + &dma_addr_hw_req, GFP_KERNEL); + if (!hwreq) { + dma_free_coherent(dev, dma_size, kbuf, dma_addr_data); + return -ENOMEM; + } + + data_size = req->cryptlen; + scatterwalk_map_and_copy(kbuf, req->src, 0, req->cryptlen, 0); + memcpy(kbuf + data_size, req->iv, GCM_AES_IV_SIZE); + + hwreq->src = dma_addr_data; + hwreq->dst = dma_addr_data; + hwreq->iv = hwreq->src + data_size; + hwreq->keysrc = tfm_ctx->keysrc; + hwreq->op = rq_ctx->op; + + if (hwreq->op == ZYNQMP_AES_ENCRYPT) + hwreq->size = data_size; + else + hwreq->size = data_size - ZYNQMP_AES_AUTH_SIZE; + + if (hwreq->keysrc == ZYNQMP_AES_KUP_KEY) { + memcpy(kbuf + data_size + GCM_AES_IV_SIZE, + tfm_ctx->key, ZYNQMP_AES_KEY_SIZE); + + hwreq->key = hwreq->src + data_size + GCM_AES_IV_SIZE; + } else { + hwreq->key = 0; + } + + ret = zynqmp_pm_aes_engine(dma_addr_hw_req, &status); + + if (ret) { + dev_err(dev, "ERROR: AES PM API failed\n"); + err = ret; + } else if (status) { + switch (status) { + case ZYNQMP_AES_GCM_TAG_MISMATCH_ERR: + dev_err(dev, "ERROR: Gcm Tag mismatch\n"); + break; + case ZYNQMP_AES_WRONG_KEY_SRC_ERR: + dev_err(dev, "ERROR: Wrong KeySrc, enable secure mode\n"); + break; + case ZYNQMP_AES_PUF_NOT_PROGRAMMED: + dev_err(dev, "ERROR: PUF is not registered\n"); + break; + default: + dev_err(dev, "ERROR: Unknown error\n"); + break; + } + err = -status; + } else { + if (hwreq->op == ZYNQMP_AES_ENCRYPT) + data_size = data_size + ZYNQMP_AES_AUTH_SIZE; + else + data_size = data_size - ZYNQMP_AES_AUTH_SIZE; + + sg_copy_from_buffer(req->dst, sg_nents(req->dst), + kbuf, data_size); + err = 0; + } + + if (kbuf) { + memzero_explicit(kbuf, dma_size); + dma_free_coherent(dev, dma_size, kbuf, dma_addr_data); + } + if (hwreq) { + memzero_explicit(hwreq, sizeof(struct zynqmp_aead_hw_req)); + dma_free_coherent(dev, sizeof(struct zynqmp_aead_hw_req), + hwreq, dma_addr_hw_req); + } + return err; +} + +static int zynqmp_fallback_check(struct zynqmp_aead_tfm_ctx *tfm_ctx, + struct aead_request *req) +{ + int need_fallback = 0; + struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req); + + if (tfm_ctx->authsize != ZYNQMP_AES_AUTH_SIZE) + need_fallback = 1; + + if (tfm_ctx->keysrc == ZYNQMP_AES_KUP_KEY && + tfm_ctx->keylen != ZYNQMP_AES_KEY_SIZE) { + need_fallback = 1; + } + if (req->assoclen != 0 || + req->cryptlen < ZYNQMP_AES_MIN_INPUT_BLK_SIZE) { + need_fallback = 1; + } + if ((req->cryptlen % ZYNQMP_AES_WORD_LEN) != 0) + need_fallback = 1; + + if (rq_ctx->op == ZYNQMP_AES_DECRYPT && + req->cryptlen <= ZYNQMP_AES_AUTH_SIZE) { + need_fallback = 1; + } + return need_fallback; +} + +static int zynqmp_handle_aes_req(struct crypto_engine *engine, + void *req) +{ + struct aead_request *areq = + container_of(req, struct aead_request, base); + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct zynqmp_aead_tfm_ctx *tfm_ctx = crypto_aead_ctx(aead); + struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(areq); + struct aead_request *subreq = aead_request_ctx(req); + int need_fallback; + int err; + + need_fallback = zynqmp_fallback_check(tfm_ctx, areq); + + if (need_fallback) { + aead_request_set_tfm(subreq, tfm_ctx->fbk_cipher); + + aead_request_set_callback(subreq, areq->base.flags, + NULL, NULL); + aead_request_set_crypt(subreq, areq->src, areq->dst, + areq->cryptlen, areq->iv); + aead_request_set_ad(subreq, areq->assoclen); + if (rq_ctx->op == ZYNQMP_AES_ENCRYPT) + err = crypto_aead_encrypt(subreq); + else + err = crypto_aead_decrypt(subreq); + } else { + err = zynqmp_aes_aead_cipher(areq); + } + + crypto_finalize_aead_request(engine, areq, err); + return 0; +} + +static int zynqmp_aes_aead_setkey(struct crypto_aead *aead, const u8 *key, + unsigned int keylen) +{ + struct crypto_tfm *tfm = crypto_aead_tfm(aead); + struct zynqmp_aead_tfm_ctx *tfm_ctx = + (struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm); + unsigned char keysrc; + + if (keylen == ZYNQMP_KEY_SRC_SEL_KEY_LEN) { + keysrc = *key; + if (keysrc == ZYNQMP_AES_KUP_KEY || + keysrc == ZYNQMP_AES_DEV_KEY || + keysrc == ZYNQMP_AES_PUF_KEY) { + tfm_ctx->keysrc = (enum zynqmp_aead_keysrc)keysrc; + } else { + tfm_ctx->keylen = keylen; + } + } else { + tfm_ctx->keylen = keylen; + if (keylen == ZYNQMP_AES_KEY_SIZE) { + tfm_ctx->keysrc = ZYNQMP_AES_KUP_KEY; + memcpy(tfm_ctx->key, key, keylen); + } + } + + tfm_ctx->fbk_cipher->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK; + tfm_ctx->fbk_cipher->base.crt_flags |= (aead->base.crt_flags & + CRYPTO_TFM_REQ_MASK); + + return crypto_aead_setkey(tfm_ctx->fbk_cipher, key, keylen); +} + +static int zynqmp_aes_aead_setauthsize(struct crypto_aead *aead, + unsigned int authsize) +{ + struct crypto_tfm *tfm = crypto_aead_tfm(aead); + struct zynqmp_aead_tfm_ctx *tfm_ctx = + (struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm); + + tfm_ctx->authsize = authsize; + return crypto_aead_setauthsize(tfm_ctx->fbk_cipher, authsize); +} + +static int zynqmp_aes_aead_encrypt(struct aead_request *req) +{ + struct zynqmp_aead_drv_ctx *drv_ctx; + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct aead_alg *alg = crypto_aead_alg(aead); + struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req); + + rq_ctx->op = ZYNQMP_AES_ENCRYPT; + drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead); + + return crypto_transfer_aead_request_to_engine(drv_ctx->engine, req); +} + +static int zynqmp_aes_aead_decrypt(struct aead_request *req) +{ + struct zynqmp_aead_drv_ctx *drv_ctx; + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct aead_alg *alg = crypto_aead_alg(aead); + struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req); + + rq_ctx->op = ZYNQMP_AES_DECRYPT; + drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead); + + return crypto_transfer_aead_request_to_engine(drv_ctx->engine, req); +} + +static int zynqmp_aes_aead_init(struct crypto_aead *aead) +{ + struct crypto_tfm *tfm = crypto_aead_tfm(aead); + struct zynqmp_aead_tfm_ctx *tfm_ctx = + (struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm); + struct zynqmp_aead_drv_ctx *drv_ctx; + struct aead_alg *alg = crypto_aead_alg(aead); + + drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead); + tfm_ctx->dev = drv_ctx->dev; + + tfm_ctx->engine_ctx.op.do_one_request = zynqmp_handle_aes_req; + tfm_ctx->engine_ctx.op.prepare_request = NULL; + tfm_ctx->engine_ctx.op.unprepare_request = NULL; + + tfm_ctx->fbk_cipher = crypto_alloc_aead(drv_ctx->alg.aead.base.cra_name, + 0, + CRYPTO_ALG_NEED_FALLBACK); + + if (IS_ERR(tfm_ctx->fbk_cipher)) { + pr_err("%s() Error: failed to allocate fallback for %s\n", + __func__, drv_ctx->alg.aead.base.cra_name); + return PTR_ERR(tfm_ctx->fbk_cipher); + } + + crypto_aead_set_reqsize(aead, + max(sizeof(struct zynqmp_aead_req_ctx), + sizeof(struct aead_request) + + crypto_aead_reqsize(tfm_ctx->fbk_cipher))); + return 0; +} + +static void zynqmp_aes_aead_exit(struct crypto_aead *aead) +{ + struct crypto_tfm *tfm = crypto_aead_tfm(aead); + struct zynqmp_aead_tfm_ctx *tfm_ctx = + (struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm); + + if (tfm_ctx->fbk_cipher) { + crypto_free_aead(tfm_ctx->fbk_cipher); + tfm_ctx->fbk_cipher = NULL; + } + memzero_explicit(tfm_ctx, sizeof(struct zynqmp_aead_tfm_ctx)); +} + +static struct zynqmp_aead_drv_ctx aes_drv_ctx = { + .alg.aead = { + .setkey = zynqmp_aes_aead_setkey, + .setauthsize = zynqmp_aes_aead_setauthsize, + .encrypt = zynqmp_aes_aead_encrypt, + .decrypt = zynqmp_aes_aead_decrypt, + .init = zynqmp_aes_aead_init, + .exit = zynqmp_aes_aead_exit, + .ivsize = GCM_AES_IV_SIZE, + .maxauthsize = ZYNQMP_AES_AUTH_SIZE, + .base = { + .cra_name = "gcm(aes)", + .cra_driver_name = "xilinx-zynqmp-aes-gcm", + .cra_priority = 200, + .cra_flags = CRYPTO_ALG_TYPE_AEAD | + CRYPTO_ALG_ASYNC | + CRYPTO_ALG_ALLOCATES_MEMORY | + CRYPTO_ALG_KERN_DRIVER_ONLY | + CRYPTO_ALG_NEED_FALLBACK, + .cra_blocksize = ZYNQMP_AES_BLK_SIZE, + .cra_ctxsize = sizeof(struct zynqmp_aead_tfm_ctx), + .cra_module = THIS_MODULE, + } + } +}; + +static int zynqmp_aes_aead_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + int err; + + /* ZynqMP AES driver supports only one instance */ + if (!aes_drv_ctx.dev) + aes_drv_ctx.dev = dev; + else + return -ENODEV; + + err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(ZYNQMP_DMA_BIT_MASK)); + if (err < 0) { + dev_err(dev, "No usable DMA configuration\n"); + return err; + } + + aes_drv_ctx.engine = crypto_engine_alloc_init(dev, 1); + if (!aes_drv_ctx.engine) { + dev_err(dev, "Cannot alloc AES engine\n"); + err = -ENOMEM; + goto err_engine; + } + + err = crypto_engine_start(aes_drv_ctx.engine); + if (err) { + dev_err(dev, "Cannot start AES engine\n"); + goto err_engine; + } + + err = crypto_register_aead(&aes_drv_ctx.alg.aead); + if (err < 0) { + dev_err(dev, "Failed to register AEAD alg.\n"); + goto err_aead; + } + return 0; + +err_aead: + crypto_unregister_aead(&aes_drv_ctx.alg.aead); + +err_engine: + if (aes_drv_ctx.engine) + crypto_engine_exit(aes_drv_ctx.engine); + + return err; +} + +static int zynqmp_aes_aead_remove(struct platform_device *pdev) +{ + crypto_engine_exit(aes_drv_ctx.engine); + crypto_unregister_aead(&aes_drv_ctx.alg.aead); + + return 0; +} + +static const struct of_device_id zynqmp_aes_dt_ids[] = { + { .compatible = "xlnx,zynqmp-aes" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, zynqmp_aes_dt_ids); + +static struct platform_driver zynqmp_aes_driver = { + .probe = zynqmp_aes_aead_probe, + .remove = zynqmp_aes_aead_remove, + .driver = { + .name = "zynqmp-aes", + .of_match_table = zynqmp_aes_dt_ids, + }, +}; + +module_platform_driver(zynqmp_aes_driver); +MODULE_LICENSE("GPL"); |