diff options
Diffstat (limited to 'drivers/crypto/caam/blob_gen.c')
| -rw-r--r-- | drivers/crypto/caam/blob_gen.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/drivers/crypto/caam/blob_gen.c b/drivers/crypto/caam/blob_gen.c new file mode 100644 index 000000000..6345c7269 --- /dev/null +++ b/drivers/crypto/caam/blob_gen.c @@ -0,0 +1,182 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2015 Pengutronix, Steffen Trumtrar <kernel@pengutronix.de> + * Copyright (C) 2021 Pengutronix, Ahmad Fatoum <kernel@pengutronix.de> + */ + +#define pr_fmt(fmt) "caam blob_gen: " fmt + +#include <linux/device.h> +#include <soc/fsl/caam-blob.h> + +#include "compat.h" +#include "desc_constr.h" +#include "desc.h" +#include "error.h" +#include "intern.h" +#include "jr.h" +#include "regs.h" + +#define CAAM_BLOB_DESC_BYTES_MAX \ + /* Command to initialize & stating length of descriptor */ \ + (CAAM_CMD_SZ + \ + /* Command to append the key-modifier + key-modifier data */ \ + CAAM_CMD_SZ + CAAM_BLOB_KEYMOD_LENGTH + \ + /* Command to include input key + pointer to the input key */ \ + CAAM_CMD_SZ + CAAM_PTR_SZ_MAX + \ + /* Command to include output key + pointer to the output key */ \ + CAAM_CMD_SZ + CAAM_PTR_SZ_MAX + \ + /* Command describing the operation to perform */ \ + CAAM_CMD_SZ) + +struct caam_blob_priv { + struct device jrdev; +}; + +struct caam_blob_job_result { + int err; + struct completion completion; +}; + +static void caam_blob_job_done(struct device *dev, u32 *desc, u32 err, void *context) +{ + struct caam_blob_job_result *res = context; + int ecode = 0; + + dev_dbg(dev, "%s %d: err 0x%x\n", __func__, __LINE__, err); + + if (err) + ecode = caam_jr_strstatus(dev, err); + + res->err = ecode; + + /* + * Upon completion, desc points to a buffer containing a CAAM job + * descriptor which encapsulates data into an externally-storable + * blob. + */ + complete(&res->completion); +} + +int caam_process_blob(struct caam_blob_priv *priv, + struct caam_blob_info *info, bool encap) +{ + struct caam_blob_job_result testres; + struct device *jrdev = &priv->jrdev; + dma_addr_t dma_in, dma_out; + int op = OP_PCLID_BLOB; + size_t output_len; + u32 *desc; + int ret; + + if (info->key_mod_len > CAAM_BLOB_KEYMOD_LENGTH) + return -EINVAL; + + if (encap) { + op |= OP_TYPE_ENCAP_PROTOCOL; + output_len = info->input_len + CAAM_BLOB_OVERHEAD; + } else { + op |= OP_TYPE_DECAP_PROTOCOL; + output_len = info->input_len - CAAM_BLOB_OVERHEAD; + } + + desc = kzalloc(CAAM_BLOB_DESC_BYTES_MAX, GFP_KERNEL | GFP_DMA); + if (!desc) + return -ENOMEM; + + dma_in = dma_map_single(jrdev, info->input, info->input_len, + DMA_TO_DEVICE); + if (dma_mapping_error(jrdev, dma_in)) { + dev_err(jrdev, "unable to map input DMA buffer\n"); + ret = -ENOMEM; + goto out_free; + } + + dma_out = dma_map_single(jrdev, info->output, output_len, + DMA_FROM_DEVICE); + if (dma_mapping_error(jrdev, dma_out)) { + dev_err(jrdev, "unable to map output DMA buffer\n"); + ret = -ENOMEM; + goto out_unmap_in; + } + + /* + * A data blob is encrypted using a blob key (BK); a random number. + * The BK is used as an AES-CCM key. The initial block (B0) and the + * initial counter (Ctr0) are generated automatically and stored in + * Class 1 Context DWords 0+1+2+3. The random BK is stored in the + * Class 1 Key Register. Operation Mode is set to AES-CCM. + */ + + init_job_desc(desc, 0); + append_key_as_imm(desc, info->key_mod, info->key_mod_len, + info->key_mod_len, CLASS_2 | KEY_DEST_CLASS_REG); + append_seq_in_ptr_intlen(desc, dma_in, info->input_len, 0); + append_seq_out_ptr_intlen(desc, dma_out, output_len, 0); + append_operation(desc, op); + + print_hex_dump_debug("data@"__stringify(__LINE__)": ", + DUMP_PREFIX_ADDRESS, 16, 1, info->input, + info->input_len, false); + print_hex_dump_debug("jobdesc@"__stringify(__LINE__)": ", + DUMP_PREFIX_ADDRESS, 16, 1, desc, + desc_bytes(desc), false); + + testres.err = 0; + init_completion(&testres.completion); + + ret = caam_jr_enqueue(jrdev, desc, caam_blob_job_done, &testres); + if (ret == -EINPROGRESS) { + wait_for_completion(&testres.completion); + ret = testres.err; + print_hex_dump_debug("output@"__stringify(__LINE__)": ", + DUMP_PREFIX_ADDRESS, 16, 1, info->output, + output_len, false); + } + + if (ret == 0) + info->output_len = output_len; + + dma_unmap_single(jrdev, dma_out, output_len, DMA_FROM_DEVICE); +out_unmap_in: + dma_unmap_single(jrdev, dma_in, info->input_len, DMA_TO_DEVICE); +out_free: + kfree(desc); + + return ret; +} +EXPORT_SYMBOL(caam_process_blob); + +struct caam_blob_priv *caam_blob_gen_init(void) +{ + struct caam_drv_private *ctrlpriv; + struct device *jrdev; + + /* + * caam_blob_gen_init() may expectedly fail with -ENODEV, e.g. when + * CAAM driver didn't probe or when SoC lacks BLOB support. An + * error would be harsh in this case, so we stick to info level. + */ + + jrdev = caam_jr_alloc(); + if (IS_ERR(jrdev)) { + pr_info("job ring requested, but none currently available\n"); + return ERR_PTR(-ENODEV); + } + + ctrlpriv = dev_get_drvdata(jrdev->parent); + if (!ctrlpriv->blob_present) { + dev_info(jrdev, "no hardware blob generation support\n"); + caam_jr_free(jrdev); + return ERR_PTR(-ENODEV); + } + + return container_of(jrdev, struct caam_blob_priv, jrdev); +} +EXPORT_SYMBOL(caam_blob_gen_init); + +void caam_blob_gen_exit(struct caam_blob_priv *priv) +{ + caam_jr_free(&priv->jrdev); +} +EXPORT_SYMBOL(caam_blob_gen_exit); |