diff options
Diffstat (limited to 'drivers/crypto/mediatek/mtk-aes.c')
-rw-r--r-- | drivers/crypto/mediatek/mtk-aes.c | 1289 |
1 files changed, 1289 insertions, 0 deletions
diff --git a/drivers/crypto/mediatek/mtk-aes.c b/drivers/crypto/mediatek/mtk-aes.c new file mode 100644 index 000000000..c2058cf59 --- /dev/null +++ b/drivers/crypto/mediatek/mtk-aes.c @@ -0,0 +1,1289 @@ +/* + * Cryptographic API. + * + * Driver for EIP97 AES acceleration. + * + * Copyright (c) 2016 Ryder Lee <ryder.lee@mediatek.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Some ideas are from atmel-aes.c drivers. + */ + +#include <crypto/aes.h> +#include <crypto/gcm.h> +#include "mtk-platform.h" + +#define AES_QUEUE_SIZE 512 +#define AES_BUF_ORDER 2 +#define AES_BUF_SIZE ((PAGE_SIZE << AES_BUF_ORDER) \ + & ~(AES_BLOCK_SIZE - 1)) +#define AES_MAX_STATE_BUF_SIZE SIZE_IN_WORDS(AES_KEYSIZE_256 + \ + AES_BLOCK_SIZE * 2) +#define AES_MAX_CT_SIZE 6 + +#define AES_CT_CTRL_HDR cpu_to_le32(0x00220000) + +/* AES-CBC/ECB/CTR command token */ +#define AES_CMD0 cpu_to_le32(0x05000000) +#define AES_CMD1 cpu_to_le32(0x2d060000) +#define AES_CMD2 cpu_to_le32(0xe4a63806) +/* AES-GCM command token */ +#define AES_GCM_CMD0 cpu_to_le32(0x0b000000) +#define AES_GCM_CMD1 cpu_to_le32(0xa0800000) +#define AES_GCM_CMD2 cpu_to_le32(0x25000010) +#define AES_GCM_CMD3 cpu_to_le32(0x0f020000) +#define AES_GCM_CMD4 cpu_to_le32(0x21e60000) +#define AES_GCM_CMD5 cpu_to_le32(0x40e60000) +#define AES_GCM_CMD6 cpu_to_le32(0xd0070000) + +/* AES transform information word 0 fields */ +#define AES_TFM_BASIC_OUT cpu_to_le32(0x4 << 0) +#define AES_TFM_BASIC_IN cpu_to_le32(0x5 << 0) +#define AES_TFM_GCM_OUT cpu_to_le32(0x6 << 0) +#define AES_TFM_GCM_IN cpu_to_le32(0xf << 0) +#define AES_TFM_SIZE(x) cpu_to_le32((x) << 8) +#define AES_TFM_128BITS cpu_to_le32(0xb << 16) +#define AES_TFM_192BITS cpu_to_le32(0xd << 16) +#define AES_TFM_256BITS cpu_to_le32(0xf << 16) +#define AES_TFM_GHASH_DIGEST cpu_to_le32(0x2 << 21) +#define AES_TFM_GHASH cpu_to_le32(0x4 << 23) +/* AES transform information word 1 fields */ +#define AES_TFM_ECB cpu_to_le32(0x0 << 0) +#define AES_TFM_CBC cpu_to_le32(0x1 << 0) +#define AES_TFM_CTR_INIT cpu_to_le32(0x2 << 0) /* init counter to 1 */ +#define AES_TFM_CTR_LOAD cpu_to_le32(0x6 << 0) /* load/reuse counter */ +#define AES_TFM_3IV cpu_to_le32(0x7 << 5) /* using IV 0-2 */ +#define AES_TFM_FULL_IV cpu_to_le32(0xf << 5) /* using IV 0-3 */ +#define AES_TFM_IV_CTR_MODE cpu_to_le32(0x1 << 10) +#define AES_TFM_ENC_HASH cpu_to_le32(0x1 << 17) + +/* AES flags */ +#define AES_FLAGS_CIPHER_MSK GENMASK(2, 0) +#define AES_FLAGS_ECB BIT(0) +#define AES_FLAGS_CBC BIT(1) +#define AES_FLAGS_CTR BIT(2) +#define AES_FLAGS_GCM BIT(3) +#define AES_FLAGS_ENCRYPT BIT(4) +#define AES_FLAGS_BUSY BIT(5) + +#define AES_AUTH_TAG_ERR cpu_to_le32(BIT(26)) + +/** + * mtk_aes_info - hardware information of AES + * @cmd: command token, hardware instruction + * @tfm: transform state of cipher algorithm. + * @state: contains keys and initial vectors. + * + * Memory layout of GCM buffer: + * /-----------\ + * | AES KEY | 128/196/256 bits + * |-----------| + * | HASH KEY | a string 128 zero bits encrypted using the block cipher + * |-----------| + * | IVs | 4 * 4 bytes + * \-----------/ + * + * The engine requires all these info to do: + * - Commands decoding and control of the engine's data path. + * - Coordinating hardware data fetch and store operations. + * - Result token construction and output. + */ +struct mtk_aes_info { + __le32 cmd[AES_MAX_CT_SIZE]; + __le32 tfm[2]; + __le32 state[AES_MAX_STATE_BUF_SIZE]; +}; + +struct mtk_aes_reqctx { + u64 mode; +}; + +struct mtk_aes_base_ctx { + struct mtk_cryp *cryp; + u32 keylen; + __le32 keymode; + + mtk_aes_fn start; + + struct mtk_aes_info info; + dma_addr_t ct_dma; + dma_addr_t tfm_dma; + + __le32 ct_hdr; + u32 ct_size; +}; + +struct mtk_aes_ctx { + struct mtk_aes_base_ctx base; +}; + +struct mtk_aes_ctr_ctx { + struct mtk_aes_base_ctx base; + + u32 iv[AES_BLOCK_SIZE / sizeof(u32)]; + size_t offset; + struct scatterlist src[2]; + struct scatterlist dst[2]; +}; + +struct mtk_aes_gcm_ctx { + struct mtk_aes_base_ctx base; + + u32 authsize; + size_t textlen; + + struct crypto_skcipher *ctr; +}; + +struct mtk_aes_drv { + struct list_head dev_list; + /* Device list lock */ + spinlock_t lock; +}; + +static struct mtk_aes_drv mtk_aes = { + .dev_list = LIST_HEAD_INIT(mtk_aes.dev_list), + .lock = __SPIN_LOCK_UNLOCKED(mtk_aes.lock), +}; + +static inline u32 mtk_aes_read(struct mtk_cryp *cryp, u32 offset) +{ + return readl_relaxed(cryp->base + offset); +} + +static inline void mtk_aes_write(struct mtk_cryp *cryp, + u32 offset, u32 value) +{ + writel_relaxed(value, cryp->base + offset); +} + +static struct mtk_cryp *mtk_aes_find_dev(struct mtk_aes_base_ctx *ctx) +{ + struct mtk_cryp *cryp = NULL; + struct mtk_cryp *tmp; + + spin_lock_bh(&mtk_aes.lock); + if (!ctx->cryp) { + list_for_each_entry(tmp, &mtk_aes.dev_list, aes_list) { + cryp = tmp; + break; + } + ctx->cryp = cryp; + } else { + cryp = ctx->cryp; + } + spin_unlock_bh(&mtk_aes.lock); + + return cryp; +} + +static inline size_t mtk_aes_padlen(size_t len) +{ + len &= AES_BLOCK_SIZE - 1; + return len ? AES_BLOCK_SIZE - len : 0; +} + +static bool mtk_aes_check_aligned(struct scatterlist *sg, size_t len, + struct mtk_aes_dma *dma) +{ + int nents; + + if (!IS_ALIGNED(len, AES_BLOCK_SIZE)) + return false; + + for (nents = 0; sg; sg = sg_next(sg), ++nents) { + if (!IS_ALIGNED(sg->offset, sizeof(u32))) + return false; + + if (len <= sg->length) { + if (!IS_ALIGNED(len, AES_BLOCK_SIZE)) + return false; + + dma->nents = nents + 1; + dma->remainder = sg->length - len; + sg->length = len; + return true; + } + + if (!IS_ALIGNED(sg->length, AES_BLOCK_SIZE)) + return false; + + len -= sg->length; + } + + return false; +} + +static inline void mtk_aes_set_mode(struct mtk_aes_rec *aes, + const struct mtk_aes_reqctx *rctx) +{ + /* Clear all but persistent flags and set request flags. */ + aes->flags = (aes->flags & AES_FLAGS_BUSY) | rctx->mode; +} + +static inline void mtk_aes_restore_sg(const struct mtk_aes_dma *dma) +{ + struct scatterlist *sg = dma->sg; + int nents = dma->nents; + + if (!dma->remainder) + return; + + while (--nents > 0 && sg) + sg = sg_next(sg); + + if (!sg) + return; + + sg->length += dma->remainder; +} + +static inline void mtk_aes_write_state_le(__le32 *dst, const u32 *src, u32 size) +{ + int i; + + for (i = 0; i < SIZE_IN_WORDS(size); i++) + dst[i] = cpu_to_le32(src[i]); +} + +static inline void mtk_aes_write_state_be(__be32 *dst, const u32 *src, u32 size) +{ + int i; + + for (i = 0; i < SIZE_IN_WORDS(size); i++) + dst[i] = cpu_to_be32(src[i]); +} + +static inline int mtk_aes_complete(struct mtk_cryp *cryp, + struct mtk_aes_rec *aes, + int err) +{ + aes->flags &= ~AES_FLAGS_BUSY; + aes->areq->complete(aes->areq, err); + /* Handle new request */ + tasklet_schedule(&aes->queue_task); + return err; +} + +/* + * Write descriptors for processing. This will configure the engine, load + * the transform information and then start the packet processing. + */ +static int mtk_aes_xmit(struct mtk_cryp *cryp, struct mtk_aes_rec *aes) +{ + struct mtk_ring *ring = cryp->ring[aes->id]; + struct mtk_desc *cmd = NULL, *res = NULL; + struct scatterlist *ssg = aes->src.sg, *dsg = aes->dst.sg; + u32 slen = aes->src.sg_len, dlen = aes->dst.sg_len; + int nents; + + /* Write command descriptors */ + for (nents = 0; nents < slen; ++nents, ssg = sg_next(ssg)) { + cmd = ring->cmd_next; + cmd->hdr = MTK_DESC_BUF_LEN(ssg->length); + cmd->buf = cpu_to_le32(sg_dma_address(ssg)); + + if (nents == 0) { + cmd->hdr |= MTK_DESC_FIRST | + MTK_DESC_CT_LEN(aes->ctx->ct_size); + cmd->ct = cpu_to_le32(aes->ctx->ct_dma); + cmd->ct_hdr = aes->ctx->ct_hdr; + cmd->tfm = cpu_to_le32(aes->ctx->tfm_dma); + } + + /* Shift ring buffer and check boundary */ + if (++ring->cmd_next == ring->cmd_base + MTK_DESC_NUM) + ring->cmd_next = ring->cmd_base; + } + cmd->hdr |= MTK_DESC_LAST; + + /* Prepare result descriptors */ + for (nents = 0; nents < dlen; ++nents, dsg = sg_next(dsg)) { + res = ring->res_next; + res->hdr = MTK_DESC_BUF_LEN(dsg->length); + res->buf = cpu_to_le32(sg_dma_address(dsg)); + + if (nents == 0) + res->hdr |= MTK_DESC_FIRST; + + /* Shift ring buffer and check boundary */ + if (++ring->res_next == ring->res_base + MTK_DESC_NUM) + ring->res_next = ring->res_base; + } + res->hdr |= MTK_DESC_LAST; + + /* Pointer to current result descriptor */ + ring->res_prev = res; + + /* Prepare enough space for authenticated tag */ + if (aes->flags & AES_FLAGS_GCM) + res->hdr += AES_BLOCK_SIZE; + + /* + * Make sure that all changes to the DMA ring are done before we + * start engine. + */ + wmb(); + /* Start DMA transfer */ + mtk_aes_write(cryp, RDR_PREP_COUNT(aes->id), MTK_DESC_CNT(dlen)); + mtk_aes_write(cryp, CDR_PREP_COUNT(aes->id), MTK_DESC_CNT(slen)); + + return -EINPROGRESS; +} + +static void mtk_aes_unmap(struct mtk_cryp *cryp, struct mtk_aes_rec *aes) +{ + struct mtk_aes_base_ctx *ctx = aes->ctx; + + dma_unmap_single(cryp->dev, ctx->ct_dma, sizeof(ctx->info), + DMA_TO_DEVICE); + + if (aes->src.sg == aes->dst.sg) { + dma_unmap_sg(cryp->dev, aes->src.sg, aes->src.nents, + DMA_BIDIRECTIONAL); + + if (aes->src.sg != &aes->aligned_sg) + mtk_aes_restore_sg(&aes->src); + } else { + dma_unmap_sg(cryp->dev, aes->dst.sg, aes->dst.nents, + DMA_FROM_DEVICE); + + if (aes->dst.sg != &aes->aligned_sg) + mtk_aes_restore_sg(&aes->dst); + + dma_unmap_sg(cryp->dev, aes->src.sg, aes->src.nents, + DMA_TO_DEVICE); + + if (aes->src.sg != &aes->aligned_sg) + mtk_aes_restore_sg(&aes->src); + } + + if (aes->dst.sg == &aes->aligned_sg) + sg_copy_from_buffer(aes->real_dst, sg_nents(aes->real_dst), + aes->buf, aes->total); +} + +static int mtk_aes_map(struct mtk_cryp *cryp, struct mtk_aes_rec *aes) +{ + struct mtk_aes_base_ctx *ctx = aes->ctx; + struct mtk_aes_info *info = &ctx->info; + + ctx->ct_dma = dma_map_single(cryp->dev, info, sizeof(*info), + DMA_TO_DEVICE); + if (unlikely(dma_mapping_error(cryp->dev, ctx->ct_dma))) + goto exit; + + ctx->tfm_dma = ctx->ct_dma + sizeof(info->cmd); + + if (aes->src.sg == aes->dst.sg) { + aes->src.sg_len = dma_map_sg(cryp->dev, aes->src.sg, + aes->src.nents, + DMA_BIDIRECTIONAL); + aes->dst.sg_len = aes->src.sg_len; + if (unlikely(!aes->src.sg_len)) + goto sg_map_err; + } else { + aes->src.sg_len = dma_map_sg(cryp->dev, aes->src.sg, + aes->src.nents, DMA_TO_DEVICE); + if (unlikely(!aes->src.sg_len)) + goto sg_map_err; + + aes->dst.sg_len = dma_map_sg(cryp->dev, aes->dst.sg, + aes->dst.nents, DMA_FROM_DEVICE); + if (unlikely(!aes->dst.sg_len)) { + dma_unmap_sg(cryp->dev, aes->src.sg, aes->src.nents, + DMA_TO_DEVICE); + goto sg_map_err; + } + } + + return mtk_aes_xmit(cryp, aes); + +sg_map_err: + dma_unmap_single(cryp->dev, ctx->ct_dma, sizeof(*info), DMA_TO_DEVICE); +exit: + return mtk_aes_complete(cryp, aes, -EINVAL); +} + +/* Initialize transform information of CBC/ECB/CTR mode */ +static void mtk_aes_info_init(struct mtk_cryp *cryp, struct mtk_aes_rec *aes, + size_t len) +{ + struct ablkcipher_request *req = ablkcipher_request_cast(aes->areq); + struct mtk_aes_base_ctx *ctx = aes->ctx; + struct mtk_aes_info *info = &ctx->info; + u32 cnt = 0; + + ctx->ct_hdr = AES_CT_CTRL_HDR | cpu_to_le32(len); + info->cmd[cnt++] = AES_CMD0 | cpu_to_le32(len); + info->cmd[cnt++] = AES_CMD1; + + info->tfm[0] = AES_TFM_SIZE(ctx->keylen) | ctx->keymode; + if (aes->flags & AES_FLAGS_ENCRYPT) + info->tfm[0] |= AES_TFM_BASIC_OUT; + else + info->tfm[0] |= AES_TFM_BASIC_IN; + + switch (aes->flags & AES_FLAGS_CIPHER_MSK) { + case AES_FLAGS_CBC: + info->tfm[1] = AES_TFM_CBC; + break; + case AES_FLAGS_ECB: + info->tfm[1] = AES_TFM_ECB; + goto ecb; + case AES_FLAGS_CTR: + info->tfm[1] = AES_TFM_CTR_LOAD; + goto ctr; + + default: + /* Should not happen... */ + return; + } + + mtk_aes_write_state_le(info->state + ctx->keylen, req->info, + AES_BLOCK_SIZE); +ctr: + info->tfm[0] += AES_TFM_SIZE(SIZE_IN_WORDS(AES_BLOCK_SIZE)); + info->tfm[1] |= AES_TFM_FULL_IV; + info->cmd[cnt++] = AES_CMD2; +ecb: + ctx->ct_size = cnt; +} + +static int mtk_aes_dma(struct mtk_cryp *cryp, struct mtk_aes_rec *aes, + struct scatterlist *src, struct scatterlist *dst, + size_t len) +{ + size_t padlen = 0; + bool src_aligned, dst_aligned; + + aes->total = len; + aes->src.sg = src; + aes->dst.sg = dst; + aes->real_dst = dst; + + src_aligned = mtk_aes_check_aligned(src, len, &aes->src); + if (src == dst) + dst_aligned = src_aligned; + else + dst_aligned = mtk_aes_check_aligned(dst, len, &aes->dst); + + if (!src_aligned || !dst_aligned) { + padlen = mtk_aes_padlen(len); + + if (len + padlen > AES_BUF_SIZE) + return mtk_aes_complete(cryp, aes, -ENOMEM); + + if (!src_aligned) { + sg_copy_to_buffer(src, sg_nents(src), aes->buf, len); + aes->src.sg = &aes->aligned_sg; + aes->src.nents = 1; + aes->src.remainder = 0; + } + + if (!dst_aligned) { + aes->dst.sg = &aes->aligned_sg; + aes->dst.nents = 1; + aes->dst.remainder = 0; + } + + sg_init_table(&aes->aligned_sg, 1); + sg_set_buf(&aes->aligned_sg, aes->buf, len + padlen); + } + + mtk_aes_info_init(cryp, aes, len + padlen); + + return mtk_aes_map(cryp, aes); +} + +static int mtk_aes_handle_queue(struct mtk_cryp *cryp, u8 id, + struct crypto_async_request *new_areq) +{ + struct mtk_aes_rec *aes = cryp->aes[id]; + struct crypto_async_request *areq, *backlog; + struct mtk_aes_base_ctx *ctx; + unsigned long flags; + int ret = 0; + + spin_lock_irqsave(&aes->lock, flags); + if (new_areq) + ret = crypto_enqueue_request(&aes->queue, new_areq); + if (aes->flags & AES_FLAGS_BUSY) { + spin_unlock_irqrestore(&aes->lock, flags); + return ret; + } + backlog = crypto_get_backlog(&aes->queue); + areq = crypto_dequeue_request(&aes->queue); + if (areq) + aes->flags |= AES_FLAGS_BUSY; + spin_unlock_irqrestore(&aes->lock, flags); + + if (!areq) + return ret; + + if (backlog) + backlog->complete(backlog, -EINPROGRESS); + + ctx = crypto_tfm_ctx(areq->tfm); + + aes->areq = areq; + aes->ctx = ctx; + + return ctx->start(cryp, aes); +} + +static int mtk_aes_transfer_complete(struct mtk_cryp *cryp, + struct mtk_aes_rec *aes) +{ + return mtk_aes_complete(cryp, aes, 0); +} + +static int mtk_aes_start(struct mtk_cryp *cryp, struct mtk_aes_rec *aes) +{ + struct ablkcipher_request *req = ablkcipher_request_cast(aes->areq); + struct mtk_aes_reqctx *rctx = ablkcipher_request_ctx(req); + + mtk_aes_set_mode(aes, rctx); + aes->resume = mtk_aes_transfer_complete; + + return mtk_aes_dma(cryp, aes, req->src, req->dst, req->nbytes); +} + +static inline struct mtk_aes_ctr_ctx * +mtk_aes_ctr_ctx_cast(struct mtk_aes_base_ctx *ctx) +{ + return container_of(ctx, struct mtk_aes_ctr_ctx, base); +} + +static int mtk_aes_ctr_transfer(struct mtk_cryp *cryp, struct mtk_aes_rec *aes) +{ + struct mtk_aes_base_ctx *ctx = aes->ctx; + struct mtk_aes_ctr_ctx *cctx = mtk_aes_ctr_ctx_cast(ctx); + struct ablkcipher_request *req = ablkcipher_request_cast(aes->areq); + struct scatterlist *src, *dst; + u32 start, end, ctr, blocks; + size_t datalen; + bool fragmented = false; + + /* Check for transfer completion. */ + cctx->offset += aes->total; + if (cctx->offset >= req->nbytes) + return mtk_aes_transfer_complete(cryp, aes); + + /* Compute data length. */ + datalen = req->nbytes - cctx->offset; + blocks = DIV_ROUND_UP(datalen, AES_BLOCK_SIZE); + ctr = be32_to_cpu(cctx->iv[3]); + + /* Check 32bit counter overflow. */ + start = ctr; + end = start + blocks - 1; + if (end < start) { + ctr |= 0xffffffff; + datalen = AES_BLOCK_SIZE * -start; + fragmented = true; + } + + /* Jump to offset. */ + src = scatterwalk_ffwd(cctx->src, req->src, cctx->offset); + dst = ((req->src == req->dst) ? src : + scatterwalk_ffwd(cctx->dst, req->dst, cctx->offset)); + + /* Write IVs into transform state buffer. */ + mtk_aes_write_state_le(ctx->info.state + ctx->keylen, cctx->iv, + AES_BLOCK_SIZE); + + if (unlikely(fragmented)) { + /* + * Increment the counter manually to cope with the hardware + * counter overflow. + */ + cctx->iv[3] = cpu_to_be32(ctr); + crypto_inc((u8 *)cctx->iv, AES_BLOCK_SIZE); + } + + return mtk_aes_dma(cryp, aes, src, dst, datalen); +} + +static int mtk_aes_ctr_start(struct mtk_cryp *cryp, struct mtk_aes_rec *aes) +{ + struct mtk_aes_ctr_ctx *cctx = mtk_aes_ctr_ctx_cast(aes->ctx); + struct ablkcipher_request *req = ablkcipher_request_cast(aes->areq); + struct mtk_aes_reqctx *rctx = ablkcipher_request_ctx(req); + + mtk_aes_set_mode(aes, rctx); + + memcpy(cctx->iv, req->info, AES_BLOCK_SIZE); + cctx->offset = 0; + aes->total = 0; + aes->resume = mtk_aes_ctr_transfer; + + return mtk_aes_ctr_transfer(cryp, aes); +} + +/* Check and set the AES key to transform state buffer */ +static int mtk_aes_setkey(struct crypto_ablkcipher *tfm, + const u8 *key, u32 keylen) +{ + struct mtk_aes_base_ctx *ctx = crypto_ablkcipher_ctx(tfm); + + switch (keylen) { + case AES_KEYSIZE_128: + ctx->keymode = AES_TFM_128BITS; + break; + case AES_KEYSIZE_192: + ctx->keymode = AES_TFM_192BITS; + break; + case AES_KEYSIZE_256: + ctx->keymode = AES_TFM_256BITS; + break; + + default: + crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); + return -EINVAL; + } + + ctx->keylen = SIZE_IN_WORDS(keylen); + mtk_aes_write_state_le(ctx->info.state, (const u32 *)key, keylen); + + return 0; +} + +static int mtk_aes_crypt(struct ablkcipher_request *req, u64 mode) +{ + struct mtk_aes_base_ctx *ctx; + struct mtk_aes_reqctx *rctx; + + ctx = crypto_ablkcipher_ctx(crypto_ablkcipher_reqtfm(req)); + rctx = ablkcipher_request_ctx(req); + rctx->mode = mode; + + return mtk_aes_handle_queue(ctx->cryp, !(mode & AES_FLAGS_ENCRYPT), + &req->base); +} + +static int mtk_aes_ecb_encrypt(struct ablkcipher_request *req) +{ + return mtk_aes_crypt(req, AES_FLAGS_ENCRYPT | AES_FLAGS_ECB); +} + +static int mtk_aes_ecb_decrypt(struct ablkcipher_request *req) +{ + return mtk_aes_crypt(req, AES_FLAGS_ECB); +} + +static int mtk_aes_cbc_encrypt(struct ablkcipher_request *req) +{ + return mtk_aes_crypt(req, AES_FLAGS_ENCRYPT | AES_FLAGS_CBC); +} + +static int mtk_aes_cbc_decrypt(struct ablkcipher_request *req) +{ + return mtk_aes_crypt(req, AES_FLAGS_CBC); +} + +static int mtk_aes_ctr_encrypt(struct ablkcipher_request *req) +{ + return mtk_aes_crypt(req, AES_FLAGS_ENCRYPT | AES_FLAGS_CTR); +} + +static int mtk_aes_ctr_decrypt(struct ablkcipher_request *req) +{ + return mtk_aes_crypt(req, AES_FLAGS_CTR); +} + +static int mtk_aes_cra_init(struct crypto_tfm *tfm) +{ + struct mtk_aes_ctx *ctx = crypto_tfm_ctx(tfm); + struct mtk_cryp *cryp = NULL; + + cryp = mtk_aes_find_dev(&ctx->base); + if (!cryp) { + pr_err("can't find crypto device\n"); + return -ENODEV; + } + + tfm->crt_ablkcipher.reqsize = sizeof(struct mtk_aes_reqctx); + ctx->base.start = mtk_aes_start; + return 0; +} + +static int mtk_aes_ctr_cra_init(struct crypto_tfm *tfm) +{ + struct mtk_aes_ctx *ctx = crypto_tfm_ctx(tfm); + struct mtk_cryp *cryp = NULL; + + cryp = mtk_aes_find_dev(&ctx->base); + if (!cryp) { + pr_err("can't find crypto device\n"); + return -ENODEV; + } + + tfm->crt_ablkcipher.reqsize = sizeof(struct mtk_aes_reqctx); + ctx->base.start = mtk_aes_ctr_start; + return 0; +} + +static struct crypto_alg aes_algs[] = { +{ + .cra_name = "cbc(aes)", + .cra_driver_name = "cbc-aes-mtk", + .cra_priority = 400, + .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | + CRYPTO_ALG_ASYNC, + .cra_init = mtk_aes_cra_init, + .cra_blocksize = AES_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct mtk_aes_ctx), + .cra_alignmask = 0xf, + .cra_type = &crypto_ablkcipher_type, + .cra_module = THIS_MODULE, + .cra_u.ablkcipher = { + .min_keysize = AES_MIN_KEY_SIZE, + .max_keysize = AES_MAX_KEY_SIZE, + .setkey = mtk_aes_setkey, + .encrypt = mtk_aes_cbc_encrypt, + .decrypt = mtk_aes_cbc_decrypt, + .ivsize = AES_BLOCK_SIZE, + } +}, +{ + .cra_name = "ecb(aes)", + .cra_driver_name = "ecb-aes-mtk", + .cra_priority = 400, + .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | + CRYPTO_ALG_ASYNC, + .cra_init = mtk_aes_cra_init, + .cra_blocksize = AES_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct mtk_aes_ctx), + .cra_alignmask = 0xf, + .cra_type = &crypto_ablkcipher_type, + .cra_module = THIS_MODULE, + .cra_u.ablkcipher = { + .min_keysize = AES_MIN_KEY_SIZE, + .max_keysize = AES_MAX_KEY_SIZE, + .setkey = mtk_aes_setkey, + .encrypt = mtk_aes_ecb_encrypt, + .decrypt = mtk_aes_ecb_decrypt, + } +}, +{ + .cra_name = "ctr(aes)", + .cra_driver_name = "ctr-aes-mtk", + .cra_priority = 400, + .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | + CRYPTO_ALG_ASYNC, + .cra_init = mtk_aes_ctr_cra_init, + .cra_blocksize = 1, + .cra_ctxsize = sizeof(struct mtk_aes_ctr_ctx), + .cra_alignmask = 0xf, + .cra_type = &crypto_ablkcipher_type, + .cra_module = THIS_MODULE, + .cra_u.ablkcipher = { + .min_keysize = AES_MIN_KEY_SIZE, + .max_keysize = AES_MAX_KEY_SIZE, + .ivsize = AES_BLOCK_SIZE, + .setkey = mtk_aes_setkey, + .encrypt = mtk_aes_ctr_encrypt, + .decrypt = mtk_aes_ctr_decrypt, + } +}, +}; + +static inline struct mtk_aes_gcm_ctx * +mtk_aes_gcm_ctx_cast(struct mtk_aes_base_ctx *ctx) +{ + return container_of(ctx, struct mtk_aes_gcm_ctx, base); +} + +/* + * Engine will verify and compare tag automatically, so we just need + * to check returned status which stored in the result descriptor. + */ +static int mtk_aes_gcm_tag_verify(struct mtk_cryp *cryp, + struct mtk_aes_rec *aes) +{ + u32 status = cryp->ring[aes->id]->res_prev->ct; + + return mtk_aes_complete(cryp, aes, (status & AES_AUTH_TAG_ERR) ? + -EBADMSG : 0); +} + +/* Initialize transform information of GCM mode */ +static void mtk_aes_gcm_info_init(struct mtk_cryp *cryp, + struct mtk_aes_rec *aes, + size_t len) +{ + struct aead_request *req = aead_request_cast(aes->areq); + struct mtk_aes_base_ctx *ctx = aes->ctx; + struct mtk_aes_gcm_ctx *gctx = mtk_aes_gcm_ctx_cast(ctx); + struct mtk_aes_info *info = &ctx->info; + u32 ivsize = crypto_aead_ivsize(crypto_aead_reqtfm(req)); + u32 cnt = 0; + + ctx->ct_hdr = AES_CT_CTRL_HDR | len; + + info->cmd[cnt++] = AES_GCM_CMD0 | cpu_to_le32(req->assoclen); + info->cmd[cnt++] = AES_GCM_CMD1 | cpu_to_le32(req->assoclen); + info->cmd[cnt++] = AES_GCM_CMD2; + info->cmd[cnt++] = AES_GCM_CMD3 | cpu_to_le32(gctx->textlen); + + if (aes->flags & AES_FLAGS_ENCRYPT) { + info->cmd[cnt++] = AES_GCM_CMD4 | cpu_to_le32(gctx->authsize); + info->tfm[0] = AES_TFM_GCM_OUT; + } else { + info->cmd[cnt++] = AES_GCM_CMD5 | cpu_to_le32(gctx->authsize); + info->cmd[cnt++] = AES_GCM_CMD6 | cpu_to_le32(gctx->authsize); + info->tfm[0] = AES_TFM_GCM_IN; + } + ctx->ct_size = cnt; + + info->tfm[0] |= AES_TFM_GHASH_DIGEST | AES_TFM_GHASH | AES_TFM_SIZE( + ctx->keylen + SIZE_IN_WORDS(AES_BLOCK_SIZE + ivsize)) | + ctx->keymode; + info->tfm[1] = AES_TFM_CTR_INIT | AES_TFM_IV_CTR_MODE | AES_TFM_3IV | + AES_TFM_ENC_HASH; + + mtk_aes_write_state_le(info->state + ctx->keylen + SIZE_IN_WORDS( + AES_BLOCK_SIZE), (const u32 *)req->iv, ivsize); +} + +static int mtk_aes_gcm_dma(struct mtk_cryp *cryp, struct mtk_aes_rec *aes, + struct scatterlist *src, struct scatterlist *dst, + size_t len) +{ + bool src_aligned, dst_aligned; + + aes->src.sg = src; + aes->dst.sg = dst; + aes->real_dst = dst; + + src_aligned = mtk_aes_check_aligned(src, len, &aes->src); + if (src == dst) + dst_aligned = src_aligned; + else + dst_aligned = mtk_aes_check_aligned(dst, len, &aes->dst); + + if (!src_aligned || !dst_aligned) { + if (aes->total > AES_BUF_SIZE) + return mtk_aes_complete(cryp, aes, -ENOMEM); + + if (!src_aligned) { + sg_copy_to_buffer(src, sg_nents(src), aes->buf, len); + aes->src.sg = &aes->aligned_sg; + aes->src.nents = 1; + aes->src.remainder = 0; + } + + if (!dst_aligned) { + aes->dst.sg = &aes->aligned_sg; + aes->dst.nents = 1; + aes->dst.remainder = 0; + } + + sg_init_table(&aes->aligned_sg, 1); + sg_set_buf(&aes->aligned_sg, aes->buf, aes->total); + } + + mtk_aes_gcm_info_init(cryp, aes, len); + + return mtk_aes_map(cryp, aes); +} + +/* Todo: GMAC */ +static int mtk_aes_gcm_start(struct mtk_cryp *cryp, struct mtk_aes_rec *aes) +{ + struct mtk_aes_gcm_ctx *gctx = mtk_aes_gcm_ctx_cast(aes->ctx); + struct aead_request *req = aead_request_cast(aes->areq); + struct mtk_aes_reqctx *rctx = aead_request_ctx(req); + u32 len = req->assoclen + req->cryptlen; + + mtk_aes_set_mode(aes, rctx); + + if (aes->flags & AES_FLAGS_ENCRYPT) { + u32 tag[4]; + + aes->resume = mtk_aes_transfer_complete; + /* Compute total process length. */ + aes->total = len + gctx->authsize; + /* Compute text length. */ + gctx->textlen = req->cryptlen; + /* Hardware will append authenticated tag to output buffer */ + scatterwalk_map_and_copy(tag, req->dst, len, gctx->authsize, 1); + } else { + aes->resume = mtk_aes_gcm_tag_verify; + aes->total = len; + gctx->textlen = req->cryptlen - gctx->authsize; + } + + return mtk_aes_gcm_dma(cryp, aes, req->src, req->dst, len); +} + +static int mtk_aes_gcm_crypt(struct aead_request *req, u64 mode) +{ + struct mtk_aes_base_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req)); + struct mtk_aes_gcm_ctx *gctx = mtk_aes_gcm_ctx_cast(ctx); + struct mtk_aes_reqctx *rctx = aead_request_ctx(req); + + /* Empty messages are not supported yet */ + if (!gctx->textlen && !req->assoclen) + return -EINVAL; + + rctx->mode = AES_FLAGS_GCM | mode; + + return mtk_aes_handle_queue(ctx->cryp, !!(mode & AES_FLAGS_ENCRYPT), + &req->base); +} + +/* + * Because of the hardware limitation, we need to pre-calculate key(H) + * for the GHASH operation. The result of the encryption operation + * need to be stored in the transform state buffer. + */ +static int mtk_aes_gcm_setkey(struct crypto_aead *aead, const u8 *key, + u32 keylen) +{ + struct mtk_aes_base_ctx *ctx = crypto_aead_ctx(aead); + struct mtk_aes_gcm_ctx *gctx = mtk_aes_gcm_ctx_cast(ctx); + struct crypto_skcipher *ctr = gctx->ctr; + struct { + u32 hash[4]; + u8 iv[8]; + + struct crypto_wait wait; + + struct scatterlist sg[1]; + struct skcipher_request req; + } *data; + int err; + + switch (keylen) { + case AES_KEYSIZE_128: + ctx->keymode = AES_TFM_128BITS; + break; + case AES_KEYSIZE_192: + ctx->keymode = AES_TFM_192BITS; + break; + case AES_KEYSIZE_256: + ctx->keymode = AES_TFM_256BITS; + break; + + default: + crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN); + return -EINVAL; + } + + ctx->keylen = SIZE_IN_WORDS(keylen); + + /* Same as crypto_gcm_setkey() from crypto/gcm.c */ + crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK); + crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) & + CRYPTO_TFM_REQ_MASK); + err = crypto_skcipher_setkey(ctr, key, keylen); + crypto_aead_set_flags(aead, crypto_skcipher_get_flags(ctr) & + CRYPTO_TFM_RES_MASK); + if (err) + return err; + + data = kzalloc(sizeof(*data) + crypto_skcipher_reqsize(ctr), + GFP_KERNEL); + if (!data) + return -ENOMEM; + + crypto_init_wait(&data->wait); + sg_init_one(data->sg, &data->hash, AES_BLOCK_SIZE); + skcipher_request_set_tfm(&data->req, ctr); + skcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP | + CRYPTO_TFM_REQ_MAY_BACKLOG, + crypto_req_done, &data->wait); + skcipher_request_set_crypt(&data->req, data->sg, data->sg, + AES_BLOCK_SIZE, data->iv); + + err = crypto_wait_req(crypto_skcipher_encrypt(&data->req), + &data->wait); + if (err) + goto out; + + /* Write key into state buffer */ + mtk_aes_write_state_le(ctx->info.state, (const u32 *)key, keylen); + /* Write key(H) into state buffer */ + mtk_aes_write_state_be(ctx->info.state + ctx->keylen, data->hash, + AES_BLOCK_SIZE); +out: + kzfree(data); + return err; +} + +static int mtk_aes_gcm_setauthsize(struct crypto_aead *aead, + u32 authsize) +{ + struct mtk_aes_base_ctx *ctx = crypto_aead_ctx(aead); + struct mtk_aes_gcm_ctx *gctx = mtk_aes_gcm_ctx_cast(ctx); + + /* Same as crypto_gcm_authsize() from crypto/gcm.c */ + switch (authsize) { + case 8: + case 12: + case 16: + break; + default: + return -EINVAL; + } + + gctx->authsize = authsize; + return 0; +} + +static int mtk_aes_gcm_encrypt(struct aead_request *req) +{ + return mtk_aes_gcm_crypt(req, AES_FLAGS_ENCRYPT); +} + +static int mtk_aes_gcm_decrypt(struct aead_request *req) +{ + return mtk_aes_gcm_crypt(req, 0); +} + +static int mtk_aes_gcm_init(struct crypto_aead *aead) +{ + struct mtk_aes_gcm_ctx *ctx = crypto_aead_ctx(aead); + struct mtk_cryp *cryp = NULL; + + cryp = mtk_aes_find_dev(&ctx->base); + if (!cryp) { + pr_err("can't find crypto device\n"); + return -ENODEV; + } + + ctx->ctr = crypto_alloc_skcipher("ctr(aes)", 0, + CRYPTO_ALG_ASYNC); + if (IS_ERR(ctx->ctr)) { + pr_err("Error allocating ctr(aes)\n"); + return PTR_ERR(ctx->ctr); + } + + crypto_aead_set_reqsize(aead, sizeof(struct mtk_aes_reqctx)); + ctx->base.start = mtk_aes_gcm_start; + return 0; +} + +static void mtk_aes_gcm_exit(struct crypto_aead *aead) +{ + struct mtk_aes_gcm_ctx *ctx = crypto_aead_ctx(aead); + + crypto_free_skcipher(ctx->ctr); +} + +static struct aead_alg aes_gcm_alg = { + .setkey = mtk_aes_gcm_setkey, + .setauthsize = mtk_aes_gcm_setauthsize, + .encrypt = mtk_aes_gcm_encrypt, + .decrypt = mtk_aes_gcm_decrypt, + .init = mtk_aes_gcm_init, + .exit = mtk_aes_gcm_exit, + .ivsize = GCM_AES_IV_SIZE, + .maxauthsize = AES_BLOCK_SIZE, + + .base = { + .cra_name = "gcm(aes)", + .cra_driver_name = "gcm-aes-mtk", + .cra_priority = 400, + .cra_flags = CRYPTO_ALG_ASYNC, + .cra_blocksize = 1, + .cra_ctxsize = sizeof(struct mtk_aes_gcm_ctx), + .cra_alignmask = 0xf, + .cra_module = THIS_MODULE, + }, +}; + +static void mtk_aes_queue_task(unsigned long data) +{ + struct mtk_aes_rec *aes = (struct mtk_aes_rec *)data; + + mtk_aes_handle_queue(aes->cryp, aes->id, NULL); +} + +static void mtk_aes_done_task(unsigned long data) +{ + struct mtk_aes_rec *aes = (struct mtk_aes_rec *)data; + struct mtk_cryp *cryp = aes->cryp; + + mtk_aes_unmap(cryp, aes); + aes->resume(cryp, aes); +} + +static irqreturn_t mtk_aes_irq(int irq, void *dev_id) +{ + struct mtk_aes_rec *aes = (struct mtk_aes_rec *)dev_id; + struct mtk_cryp *cryp = aes->cryp; + u32 val = mtk_aes_read(cryp, RDR_STAT(aes->id)); + + mtk_aes_write(cryp, RDR_STAT(aes->id), val); + + if (likely(AES_FLAGS_BUSY & aes->flags)) { + mtk_aes_write(cryp, RDR_PROC_COUNT(aes->id), MTK_CNT_RST); + mtk_aes_write(cryp, RDR_THRESH(aes->id), + MTK_RDR_PROC_THRESH | MTK_RDR_PROC_MODE); + + tasklet_schedule(&aes->done_task); + } else { + dev_warn(cryp->dev, "AES interrupt when no active requests.\n"); + } + return IRQ_HANDLED; +} + +/* + * The purpose of creating encryption and decryption records is + * to process outbound/inbound data in parallel, it can improve + * performance in most use cases, such as IPSec VPN, especially + * under heavy network traffic. + */ +static int mtk_aes_record_init(struct mtk_cryp *cryp) +{ + struct mtk_aes_rec **aes = cryp->aes; + int i, err = -ENOMEM; + + for (i = 0; i < MTK_REC_NUM; i++) { + aes[i] = kzalloc(sizeof(**aes), GFP_KERNEL); + if (!aes[i]) + goto err_cleanup; + + aes[i]->buf = (void *)__get_free_pages(GFP_KERNEL, + AES_BUF_ORDER); + if (!aes[i]->buf) + goto err_cleanup; + + aes[i]->cryp = cryp; + + spin_lock_init(&aes[i]->lock); + crypto_init_queue(&aes[i]->queue, AES_QUEUE_SIZE); + + tasklet_init(&aes[i]->queue_task, mtk_aes_queue_task, + (unsigned long)aes[i]); + tasklet_init(&aes[i]->done_task, mtk_aes_done_task, + (unsigned long)aes[i]); + } + + /* Link to ring0 and ring1 respectively */ + aes[0]->id = MTK_RING0; + aes[1]->id = MTK_RING1; + + return 0; + +err_cleanup: + for (; i--; ) { + free_page((unsigned long)aes[i]->buf); + kfree(aes[i]); + } + + return err; +} + +static void mtk_aes_record_free(struct mtk_cryp *cryp) +{ + int i; + + for (i = 0; i < MTK_REC_NUM; i++) { + tasklet_kill(&cryp->aes[i]->done_task); + tasklet_kill(&cryp->aes[i]->queue_task); + + free_page((unsigned long)cryp->aes[i]->buf); + kfree(cryp->aes[i]); + } +} + +static void mtk_aes_unregister_algs(void) +{ + int i; + + crypto_unregister_aead(&aes_gcm_alg); + + for (i = 0; i < ARRAY_SIZE(aes_algs); i++) + crypto_unregister_alg(&aes_algs[i]); +} + +static int mtk_aes_register_algs(void) +{ + int err, i; + + for (i = 0; i < ARRAY_SIZE(aes_algs); i++) { + err = crypto_register_alg(&aes_algs[i]); + if (err) + goto err_aes_algs; + } + + err = crypto_register_aead(&aes_gcm_alg); + if (err) + goto err_aes_algs; + + return 0; + +err_aes_algs: + for (; i--; ) + crypto_unregister_alg(&aes_algs[i]); + + return err; +} + +int mtk_cipher_alg_register(struct mtk_cryp *cryp) +{ + int ret; + + INIT_LIST_HEAD(&cryp->aes_list); + + /* Initialize two cipher records */ + ret = mtk_aes_record_init(cryp); + if (ret) + goto err_record; + + ret = devm_request_irq(cryp->dev, cryp->irq[MTK_RING0], mtk_aes_irq, + 0, "mtk-aes", cryp->aes[0]); + if (ret) { + dev_err(cryp->dev, "unable to request AES irq.\n"); + goto err_res; + } + + ret = devm_request_irq(cryp->dev, cryp->irq[MTK_RING1], mtk_aes_irq, + 0, "mtk-aes", cryp->aes[1]); + if (ret) { + dev_err(cryp->dev, "unable to request AES irq.\n"); + goto err_res; + } + + /* Enable ring0 and ring1 interrupt */ + mtk_aes_write(cryp, AIC_ENABLE_SET(MTK_RING0), MTK_IRQ_RDR0); + mtk_aes_write(cryp, AIC_ENABLE_SET(MTK_RING1), MTK_IRQ_RDR1); + + spin_lock(&mtk_aes.lock); + list_add_tail(&cryp->aes_list, &mtk_aes.dev_list); + spin_unlock(&mtk_aes.lock); + + ret = mtk_aes_register_algs(); + if (ret) + goto err_algs; + + return 0; + +err_algs: + spin_lock(&mtk_aes.lock); + list_del(&cryp->aes_list); + spin_unlock(&mtk_aes.lock); +err_res: + mtk_aes_record_free(cryp); +err_record: + + dev_err(cryp->dev, "mtk-aes initialization failed.\n"); + return ret; +} + +void mtk_cipher_alg_release(struct mtk_cryp *cryp) +{ + spin_lock(&mtk_aes.lock); + list_del(&cryp->aes_list); + spin_unlock(&mtk_aes.lock); + + mtk_aes_unregister_algs(); + mtk_aes_record_free(cryp); +} |