| // 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/err.h> |
| #include <linux/firmware/xlnx-zynqmp.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/mod_devicetable.h> |
| #include <linux/platform_device.h> |
| #include <linux/string.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_engine_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 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.base); |
| |
| 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.base); |
| |
| 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.base); |
| tfm_ctx->dev = drv_ctx->dev; |
| |
| tfm_ctx->fbk_cipher = crypto_alloc_aead(drv_ctx->alg.aead.base.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.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.base = { |
| .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, |
| } |
| }, |
| .alg.aead.op = { |
| .do_one_request = zynqmp_handle_aes_req, |
| }, |
| }; |
| |
| 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_engine_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_engine_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_engine_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"); |