include/soc/fsl/caam-blob.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 2020 Pengutronix, Ahmad Fatoum <kernel@pengutronix.de>
   4  */
   5
   6 #ifndef __CAAM_BLOB_GEN
   7 #define __CAAM_BLOB_GEN
   8
   9 #include <linux/types.h>
  10 #include <linux/errno.h>
  11
  12 #define CAAM_BLOB_KEYMOD_LENGTH         16
  13 #define CAAM_BLOB_OVERHEAD              (32 + 16)
  14 #define CAAM_BLOB_MAX_LEN               4096
  15
  16 struct caam_blob_priv;
  17
  18 /**
  19  * struct caam_blob_info - information for CAAM blobbing
  20  * @input:       pointer to input buffer (must be DMAable)
  21  * @input_len:   length of @input buffer in bytes.
  22  * @output:      pointer to output buffer (must be DMAable)
  23  * @output_len:  length of @output buffer in bytes.
  24  * @key_mod:     key modifier
  25  * @key_mod_len: length of @key_mod in bytes.
  26  *               May not exceed %CAAM_BLOB_KEYMOD_LENGTH
  27  */
  28 struct caam_blob_info {
  29         void *input;
  30         size_t input_len;
  31
  32         void *output;
  33         size_t output_len;
  34
  35         const void *key_mod;
  36         size_t key_mod_len;
  37 };
  38
  39 /**
  40  * caam_blob_gen_init - initialize blob generation
  41  * Return: pointer to new &struct caam_blob_priv instance on success
  42  * and ``ERR_PTR(-ENODEV)`` if CAAM has no hardware blobbing support
  43  * or no job ring could be allocated.
  44  */
  45 struct caam_blob_priv *caam_blob_gen_init(void);
  46
  47 /**
  48  * caam_blob_gen_exit - free blob generation resources
  49  * @priv: instance returned by caam_blob_gen_init()
  50  */
  51 void caam_blob_gen_exit(struct caam_blob_priv *priv);
  52
  53 /**
  54  * caam_process_blob - encapsulate or decapsulate blob
  55  * @priv:   instance returned by caam_blob_gen_init()
  56  * @info:   pointer to blobbing info describing key, blob and
  57  *          key modifier buffers.
  58  * @encap:  true for encapsulation, false for decapsulation
  59  *
  60  * Return: %0 and sets ``info->output_len`` on success and a negative
  61  * error code otherwise.
  62  */
  63 int caam_process_blob(struct caam_blob_priv *priv,
  64                       struct caam_blob_info *info, bool encap);
  65
  66 /**
  67  * caam_encap_blob - encapsulate blob
  68  * @priv:   instance returned by caam_blob_gen_init()
  69  * @info:   pointer to blobbing info describing input key,
  70  *          output blob and key modifier buffers.
  71  *
  72  * Return: %0 and sets ``info->output_len`` on success and
  73  * a negative error code otherwise.
  74  */
  75 static inline int caam_encap_blob(struct caam_blob_priv *priv,
  76                                   struct caam_blob_info *info)
  77 {
  78         if (info->output_len < info->input_len + CAAM_BLOB_OVERHEAD)
  79                 return -EINVAL;
  80
  81         return caam_process_blob(priv, info, true);
  82 }
  83
  84 /**
  85  * caam_decap_blob - decapsulate blob
  86  * @priv:   instance returned by caam_blob_gen_init()
  87  * @info:   pointer to blobbing info describing output key,
  88  *          input blob and key modifier buffers.
  89  *
  90  * Return: %0 and sets ``info->output_len`` on success and
  91  * a negative error code otherwise.
  92  */
  93 static inline int caam_decap_blob(struct caam_blob_priv *priv,
  94                                   struct caam_blob_info *info)
  95 {
  96         if (info->input_len < CAAM_BLOB_OVERHEAD ||
  97             info->output_len < info->input_len - CAAM_BLOB_OVERHEAD)
  98                 return -EINVAL;
  99
 100         return caam_process_blob(priv, info, false);
 101 }
 102
 103 #endif