From d03f7b0d58ac1bed9d98960dfe831f69a6f15aab Mon Sep 17 00:00:00 2001 From: Ryder Lee Date: Fri, 20 Jan 2017 13:41:15 +0800 Subject: [PATCH] crypto: mediatek - add support to GCM mode This patch adds support to the GCM mode. Signed-off-by: Ryder Lee Signed-off-by: Herbert Xu --- drivers/crypto/Kconfig | 2 + drivers/crypto/mediatek/mtk-aes.c | 369 ++++++++++++++++++++++++- drivers/crypto/mediatek/mtk-platform.h | 2 + 3 files changed, 369 insertions(+), 4 deletions(-) diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig index ee5057a2914b..bf7da55cffe6 100644 --- a/drivers/crypto/Kconfig +++ b/drivers/crypto/Kconfig @@ -557,7 +557,9 @@ config CRYPTO_DEV_MEDIATEK tristate "MediaTek's EIP97 Cryptographic Engine driver" depends on (ARM && ARCH_MEDIATEK) || COMPILE_TEST select CRYPTO_AES + select CRYPTO_AEAD select CRYPTO_BLKCIPHER + select CRYPTO_CTR select CRYPTO_SHA1 select CRYPTO_SHA256 select CRYPTO_SHA512 diff --git a/drivers/crypto/mediatek/mtk-aes.c b/drivers/crypto/mediatek/mtk-aes.c index bb5b4ff9ab0d..3a47cdb8f0c8 100644 --- a/drivers/crypto/mediatek/mtk-aes.c +++ b/drivers/crypto/mediatek/mtk-aes.c @@ -24,16 +24,28 @@ #define AES_CT_SIZE_ECB 2 #define AES_CT_SIZE_CBC 3 #define AES_CT_SIZE_CTR 3 +#define AES_CT_SIZE_GCM_OUT 5 +#define AES_CT_SIZE_GCM_IN 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) @@ -41,15 +53,22 @@ /* 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) +#define AES_TFM_GHASH_DIG cpu_to_le32(0x2 << 21) +#define AES_TFM_GHASH cpu_to_le32(0x4 << 23) /* AES flags */ #define AES_FLAGS_ECB BIT(0) #define AES_FLAGS_CBC BIT(1) #define AES_FLAGS_CTR BIT(2) -#define AES_FLAGS_ENCRYPT BIT(3) -#define AES_FLAGS_BUSY BIT(4) +#define AES_FLAGS_GCM BIT(3) +#define AES_FLAGS_ENCRYPT BIT(4) +#define AES_FLAGS_BUSY BIT(5) /** * Command token(CT) is a set of hardware instructions that @@ -62,14 +81,23 @@ * - Commands decoding and control of the engine's data path. * - Coordinating hardware data fetch and store operations. * - Result token construction and output. + * + * Memory map of GCM's TFM: + * /-----------\ + * | AES KEY | 128/196/256 bits + * |-----------| + * | HASH KEY | a string 128 zero bits encrypted using the block cipher + * |-----------| + * | IVs | 4 * 4 bytes + * \-----------/ */ struct mtk_aes_ct { - __le32 cmd[AES_CT_SIZE_CBC]; + __le32 cmd[AES_CT_SIZE_GCM_IN]; }; struct mtk_aes_tfm { __le32 ctrl[2]; - __le32 state[SIZE_IN_WORDS(AES_KEYSIZE_256 + AES_BLOCK_SIZE)]; + __le32 state[SIZE_IN_WORDS(AES_KEYSIZE_256 + AES_BLOCK_SIZE * 2)]; }; struct mtk_aes_reqctx { @@ -103,6 +131,20 @@ struct mtk_aes_ctr_ctx { 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_gcm_setkey_result { + int err; + struct completion completion; +}; + struct mtk_aes_drv { struct list_head dev_list; /* Device list lock */ @@ -251,6 +293,10 @@ static int mtk_aes_xmit(struct mtk_cryp *cryp, struct mtk_aes_rec *aes) } res->hdr |= MTK_DESC_LAST; + /* 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. @@ -737,6 +783,315 @@ static struct crypto_alg aes_algs[] = { }, }; +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); +} + +/* 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); + const u32 *iv = (const u32 *)req->iv; + u32 *iv_state = ctx->tfm.state + ctx->keylen + + SIZE_IN_WORDS(AES_BLOCK_SIZE); + u32 ivsize = crypto_aead_ivsize(crypto_aead_reqtfm(req)); + int i; + + ctx->ct_hdr = AES_CT_CTRL_HDR | len; + + ctx->ct.cmd[0] = AES_GCM_CMD0 | cpu_to_le32(req->assoclen); + ctx->ct.cmd[1] = AES_GCM_CMD1 | cpu_to_le32(req->assoclen); + ctx->ct.cmd[2] = AES_GCM_CMD2; + ctx->ct.cmd[3] = AES_GCM_CMD3 | cpu_to_le32(gctx->textlen); + + if (aes->flags & AES_FLAGS_ENCRYPT) { + ctx->ct.cmd[4] = AES_GCM_CMD4 | cpu_to_le32(gctx->authsize); + ctx->ct_size = AES_CT_SIZE_GCM_OUT; + ctx->tfm.ctrl[0] = AES_TFM_GCM_OUT; + } else { + ctx->ct.cmd[4] = AES_GCM_CMD5 | cpu_to_le32(gctx->authsize); + ctx->ct.cmd[5] = AES_GCM_CMD6 | cpu_to_le32(gctx->authsize); + ctx->ct_size = AES_CT_SIZE_GCM_IN; + ctx->tfm.ctrl[0] = AES_TFM_GCM_IN; + } + + if (ctx->keylen == SIZE_IN_WORDS(AES_KEYSIZE_128)) + ctx->tfm.ctrl[0] |= AES_TFM_128BITS; + else if (ctx->keylen == SIZE_IN_WORDS(AES_KEYSIZE_256)) + ctx->tfm.ctrl[0] |= AES_TFM_256BITS; + else + ctx->tfm.ctrl[0] |= AES_TFM_192BITS; + + ctx->tfm.ctrl[0] |= AES_TFM_GHASH_DIG | AES_TFM_GHASH | + AES_TFM_SIZE(ctx->keylen + SIZE_IN_WORDS( + AES_BLOCK_SIZE + ivsize)); + ctx->tfm.ctrl[1] = AES_TFM_CTR_INIT | AES_TFM_IV_CTR_MODE | + AES_TFM_3IV | AES_TFM_ENC_HASH; + + for (i = 0; i < SIZE_IN_WORDS(ivsize); i++) + iv_state[i] = cpu_to_le32(iv[i]); +} + +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 -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]; + /* 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->total = len; + gctx->textlen = req->cryptlen - gctx->authsize; + } + aes->resume = mtk_aes_complete; + + 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_reqctx *rctx = aead_request_ctx(req); + + rctx->mode = AES_FLAGS_GCM | mode; + + return mtk_aes_handle_queue(ctx->cryp, !!(mode & AES_FLAGS_ENCRYPT), + &req->base); +} + +static void mtk_gcm_setkey_done(struct crypto_async_request *req, int err) +{ + struct mtk_aes_gcm_setkey_result *result = req->data; + + if (err == -EINPROGRESS) + return; + + result->err = err; + complete(&result->completion); +} + +/* + * 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 mtk_aes_gcm_setkey_result result; + + struct scatterlist sg[1]; + struct skcipher_request req; + } *data; + const u32 *aes_key; + u32 *key_state, *hash_state; + int err, i; + + if (keylen != AES_KEYSIZE_256 && + keylen != AES_KEYSIZE_192 && + keylen != AES_KEYSIZE_128) { + crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN); + return -EINVAL; + } + + key_state = ctx->tfm.state; + aes_key = (u32 *)key; + ctx->keylen = SIZE_IN_WORDS(keylen); + + for (i = 0; i < ctx->keylen; i++) + ctx->tfm.state[i] = cpu_to_le32(aes_key[i]); + + /* 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; + + init_completion(&data->result.completion); + 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, + mtk_gcm_setkey_done, &data->result); + skcipher_request_set_crypt(&data->req, data->sg, data->sg, + AES_BLOCK_SIZE, data->iv); + + err = crypto_skcipher_encrypt(&data->req); + if (err == -EINPROGRESS || err == -EBUSY) { + err = wait_for_completion_interruptible( + &data->result.completion); + if (!err) + err = data->result.err; + } + if (err) + goto out; + + hash_state = key_state + ctx->keylen; + + for (i = 0; i < 4; i++) + hash_state[i] = cpu_to_be32(data->hash[i]); +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 = 12, + .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_enc_task(unsigned long data) { struct mtk_cryp *cryp = (struct mtk_cryp *)data; @@ -851,6 +1206,8 @@ 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]); } @@ -865,6 +1222,10 @@ static int mtk_aes_register_algs(void) goto err_aes_algs; } + err = crypto_register_aead(&aes_gcm_alg); + if (err) + goto err_aes_algs; + return 0; err_aes_algs: diff --git a/drivers/crypto/mediatek/mtk-platform.h b/drivers/crypto/mediatek/mtk-platform.h index 7cd5f98d25a5..ed6d8717f7f4 100644 --- a/drivers/crypto/mediatek/mtk-platform.h +++ b/drivers/crypto/mediatek/mtk-platform.h @@ -13,8 +13,10 @@ #define __MTK_PLATFORM_H_ #include +#include #include #include +#include #include #include #include -- 2.20.1