diff options
Diffstat (limited to 'drivers/crypto/caam/caampkc.c')
| -rw-r--r-- | drivers/crypto/caam/caampkc.c | 177 |
1 files changed, 104 insertions, 73 deletions
diff --git a/drivers/crypto/caam/caampkc.c b/drivers/crypto/caam/caampkc.c index fe24485274e1..80574106af29 100644 --- a/drivers/crypto/caam/caampkc.c +++ b/drivers/crypto/caam/caampkc.c @@ -3,7 +3,7 @@ * caam - Freescale FSL CAAM support for Public Key Cryptography * * Copyright 2016 Freescale Semiconductor, Inc. - * Copyright 2018 NXP + * Copyright 2018-2019 NXP * * There is no Shared Descriptor for PKC so that the Job Descriptor must carry * all the desired key parameters, input and output pointers. @@ -24,12 +24,18 @@ sizeof(struct rsa_priv_f2_pdb)) #define DESC_RSA_PRIV_F3_LEN (2 * CAAM_CMD_SZ + \ sizeof(struct rsa_priv_f3_pdb)) +#define CAAM_RSA_MAX_INPUT_SIZE 512 /* for a 4096-bit modulus */ + +/* buffer filled with zeros, used for padding */ +static u8 *zero_buffer; static void rsa_io_unmap(struct device *dev, struct rsa_edesc *edesc, struct akcipher_request *req) { + struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req); + dma_unmap_sg(dev, req->dst, edesc->dst_nents, DMA_FROM_DEVICE); - dma_unmap_sg(dev, req->src, edesc->src_nents, DMA_TO_DEVICE); + dma_unmap_sg(dev, req_ctx->fixup_src, edesc->src_nents, DMA_TO_DEVICE); if (edesc->sec4_sg_bytes) dma_unmap_single(dev, edesc->sec4_sg_dma, edesc->sec4_sg_bytes, @@ -168,6 +174,13 @@ static void rsa_priv_f3_done(struct device *dev, u32 *desc, u32 err, akcipher_request_complete(req, err); } +/** + * Count leading zeros, need it to strip, from a given scatterlist + * + * @sgl : scatterlist to count zeros from + * @nbytes: number of zeros, in bytes, to strip + * @flags : operation flags + */ static int caam_rsa_count_leading_zeros(struct scatterlist *sgl, unsigned int nbytes, unsigned int flags) @@ -187,7 +200,8 @@ static int caam_rsa_count_leading_zeros(struct scatterlist *sgl, lzeros = 0; len = 0; while (nbytes > 0) { - while (len && !*buff) { + /* do not strip more than given bytes */ + while (len && !*buff && lzeros < nbytes) { lzeros++; len--; buff++; @@ -218,6 +232,7 @@ static struct rsa_edesc *rsa_edesc_alloc(struct akcipher_request *req, struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm); struct device *dev = ctx->dev; struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req); + struct caam_rsa_key *key = &ctx->key; struct rsa_edesc *edesc; gfp_t flags = (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ? GFP_KERNEL : GFP_ATOMIC; @@ -225,22 +240,45 @@ static struct rsa_edesc *rsa_edesc_alloc(struct akcipher_request *req, int sgc; int sec4_sg_index, sec4_sg_len = 0, sec4_sg_bytes; int src_nents, dst_nents; + unsigned int diff_size = 0; int lzeros; - lzeros = caam_rsa_count_leading_zeros(req->src, req->src_len, sg_flags); - if (lzeros < 0) - return ERR_PTR(lzeros); - - req->src_len -= lzeros; - req->src = scatterwalk_ffwd(req_ctx->src, req->src, lzeros); + if (req->src_len > key->n_sz) { + /* + * strip leading zeros and + * return the number of zeros to skip + */ + lzeros = caam_rsa_count_leading_zeros(req->src, req->src_len - + key->n_sz, sg_flags); + if (lzeros < 0) + return ERR_PTR(lzeros); + + req_ctx->fixup_src = scatterwalk_ffwd(req_ctx->src, req->src, + lzeros); + req_ctx->fixup_src_len = req->src_len - lzeros; + } else { + /* + * input src is less then n key modulus, + * so there will be zero padding + */ + diff_size = key->n_sz - req->src_len; + req_ctx->fixup_src = req->src; + req_ctx->fixup_src_len = req->src_len; + } - src_nents = sg_nents_for_len(req->src, req->src_len); + src_nents = sg_nents_for_len(req_ctx->fixup_src, + req_ctx->fixup_src_len); dst_nents = sg_nents_for_len(req->dst, req->dst_len); - if (src_nents > 1) - sec4_sg_len = src_nents; + if (!diff_size && src_nents == 1) + sec4_sg_len = 0; /* no need for an input hw s/g table */ + else + sec4_sg_len = src_nents + !!diff_size; + sec4_sg_index = sec4_sg_len; if (dst_nents > 1) - sec4_sg_len += dst_nents; + sec4_sg_len += pad_sg_nents(dst_nents); + else + sec4_sg_len = pad_sg_nents(sec4_sg_len); sec4_sg_bytes = sec4_sg_len * sizeof(struct sec4_sg_entry); @@ -250,7 +288,7 @@ static struct rsa_edesc *rsa_edesc_alloc(struct akcipher_request *req, if (!edesc) return ERR_PTR(-ENOMEM); - sgc = dma_map_sg(dev, req->src, src_nents, DMA_TO_DEVICE); + sgc = dma_map_sg(dev, req_ctx->fixup_src, src_nents, DMA_TO_DEVICE); if (unlikely(!sgc)) { dev_err(dev, "unable to map source\n"); goto src_fail; @@ -263,14 +301,16 @@ static struct rsa_edesc *rsa_edesc_alloc(struct akcipher_request *req, } edesc->sec4_sg = (void *)edesc + sizeof(*edesc) + desclen; + if (diff_size) + dma_to_sec4_sg_one(edesc->sec4_sg, ctx->padding_dma, diff_size, + 0); + + if (sec4_sg_index) + sg_to_sec4_sg_last(req_ctx->fixup_src, req_ctx->fixup_src_len, + edesc->sec4_sg + !!diff_size, 0); - sec4_sg_index = 0; - if (src_nents > 1) { - sg_to_sec4_sg_last(req->src, src_nents, edesc->sec4_sg, 0); - sec4_sg_index += src_nents; - } if (dst_nents > 1) - sg_to_sec4_sg_last(req->dst, dst_nents, + sg_to_sec4_sg_last(req->dst, req->dst_len, edesc->sec4_sg + sec4_sg_index, 0); /* Save nents for later use in Job Descriptor */ @@ -289,12 +329,16 @@ static struct rsa_edesc *rsa_edesc_alloc(struct akcipher_request *req, edesc->sec4_sg_bytes = sec4_sg_bytes; + print_hex_dump_debug("caampkc sec4_sg@" __stringify(__LINE__) ": ", + DUMP_PREFIX_ADDRESS, 16, 4, edesc->sec4_sg, + edesc->sec4_sg_bytes, 1); + return edesc; sec4_sg_fail: dma_unmap_sg(dev, req->dst, dst_nents, DMA_FROM_DEVICE); dst_fail: - dma_unmap_sg(dev, req->src, src_nents, DMA_TO_DEVICE); + dma_unmap_sg(dev, req_ctx->fixup_src, src_nents, DMA_TO_DEVICE); src_fail: kfree(edesc); return ERR_PTR(-ENOMEM); @@ -304,6 +348,7 @@ static int set_rsa_pub_pdb(struct akcipher_request *req, struct rsa_edesc *edesc) { struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); + struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req); struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm); struct caam_rsa_key *key = &ctx->key; struct device *dev = ctx->dev; @@ -328,7 +373,7 @@ static int set_rsa_pub_pdb(struct akcipher_request *req, pdb->f_dma = edesc->sec4_sg_dma; sec4_sg_index += edesc->src_nents; } else { - pdb->f_dma = sg_dma_address(req->src); + pdb->f_dma = sg_dma_address(req_ctx->fixup_src); } if (edesc->dst_nents > 1) { @@ -340,7 +385,7 @@ static int set_rsa_pub_pdb(struct akcipher_request *req, } pdb->sgf |= (key->e_sz << RSA_PDB_E_SHIFT) | key->n_sz; - pdb->f_len = req->src_len; + pdb->f_len = req_ctx->fixup_src_len; return 0; } @@ -373,7 +418,9 @@ static int set_rsa_priv_f1_pdb(struct akcipher_request *req, pdb->g_dma = edesc->sec4_sg_dma; sec4_sg_index += edesc->src_nents; } else { - pdb->g_dma = sg_dma_address(req->src); + struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req); + + pdb->g_dma = sg_dma_address(req_ctx->fixup_src); } if (edesc->dst_nents > 1) { @@ -436,7 +483,9 @@ static int set_rsa_priv_f2_pdb(struct akcipher_request *req, pdb->g_dma = edesc->sec4_sg_dma; sec4_sg_index += edesc->src_nents; } else { - pdb->g_dma = sg_dma_address(req->src); + struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req); + + pdb->g_dma = sg_dma_address(req_ctx->fixup_src); } if (edesc->dst_nents > 1) { @@ -523,7 +572,9 @@ static int set_rsa_priv_f3_pdb(struct akcipher_request *req, pdb->g_dma = edesc->sec4_sg_dma; sec4_sg_index += edesc->src_nents; } else { - pdb->g_dma = sg_dma_address(req->src); + struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req); + + pdb->g_dma = sg_dma_address(req_ctx->fixup_src); } if (edesc->dst_nents > 1) { @@ -978,6 +1029,15 @@ static int caam_rsa_init_tfm(struct crypto_akcipher *tfm) return PTR_ERR(ctx->dev); } + ctx->padding_dma = dma_map_single(ctx->dev, zero_buffer, + CAAM_RSA_MAX_INPUT_SIZE - 1, + DMA_TO_DEVICE); + if (dma_mapping_error(ctx->dev, ctx->padding_dma)) { + dev_err(ctx->dev, "unable to map padding\n"); + caam_jr_free(ctx->dev); + return -ENOMEM; + } + return 0; } @@ -987,6 +1047,8 @@ static void caam_rsa_exit_tfm(struct crypto_akcipher *tfm) struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm); struct caam_rsa_key *key = &ctx->key; + dma_unmap_single(ctx->dev, ctx->padding_dma, CAAM_RSA_MAX_INPUT_SIZE - + 1, DMA_TO_DEVICE); caam_rsa_free_key(key); caam_jr_free(ctx->dev); } @@ -1010,41 +1072,12 @@ static struct akcipher_alg caam_rsa = { }; /* Public Key Cryptography module initialization handler */ -static int __init caam_pkc_init(void) +int caam_pkc_init(struct device *ctrldev) { - struct device_node *dev_node; - struct platform_device *pdev; - struct device *ctrldev; - struct caam_drv_private *priv; + struct caam_drv_private *priv = dev_get_drvdata(ctrldev); u32 pk_inst; int err; - dev_node = of_find_compatible_node(NULL, NULL, "fsl,sec-v4.0"); - if (!dev_node) { - dev_node = of_find_compatible_node(NULL, NULL, "fsl,sec4.0"); - if (!dev_node) - return -ENODEV; - } - - pdev = of_find_device_by_node(dev_node); - if (!pdev) { - of_node_put(dev_node); - return -ENODEV; - } - - ctrldev = &pdev->dev; - priv = dev_get_drvdata(ctrldev); - of_node_put(dev_node); - - /* - * If priv is NULL, it's probably because the caam driver wasn't - * properly initialized (e.g. RNG4 init failed). Thus, bail out here. - */ - if (!priv) { - err = -ENODEV; - goto out_put_dev; - } - /* Determine public key hardware accelerator presence. */ if (priv->era < 10) pk_inst = (rd_reg32(&priv->ctrl->perfmon.cha_num_ls) & @@ -1053,31 +1086,29 @@ static int __init caam_pkc_init(void) pk_inst = rd_reg32(&priv->ctrl->vreg.pkha) & CHA_VER_NUM_MASK; /* Do not register algorithms if PKHA is not present. */ - if (!pk_inst) { - err = -ENODEV; - goto out_put_dev; - } + if (!pk_inst) + return 0; + + /* allocate zero buffer, used for padding input */ + zero_buffer = kzalloc(CAAM_RSA_MAX_INPUT_SIZE - 1, GFP_DMA | + GFP_KERNEL); + if (!zero_buffer) + return -ENOMEM; err = crypto_register_akcipher(&caam_rsa); - if (err) + if (err) { + kfree(zero_buffer); dev_warn(ctrldev, "%s alg registration failed\n", caam_rsa.base.cra_driver_name); - else + } else { dev_info(ctrldev, "caam pkc algorithms registered in /proc/crypto\n"); + } -out_put_dev: - put_device(ctrldev); return err; } -static void __exit caam_pkc_exit(void) +void caam_pkc_exit(void) { + kfree(zero_buffer); crypto_unregister_akcipher(&caam_rsa); } - -module_init(caam_pkc_init); -module_exit(caam_pkc_exit); - -MODULE_LICENSE("Dual BSD/GPL"); -MODULE_DESCRIPTION("FSL CAAM support for PKC functions of crypto API"); -MODULE_AUTHOR("Freescale Semiconductor"); |