aead_api.c 2.6 KB

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  1. // SPDX-License-Identifier: GPL-2.0-only
  2. /*
  3. * Copyright 2003-2004, Instant802 Networks, Inc.
  4. * Copyright 2005-2006, Devicescape Software, Inc.
  5. * Copyright 2014-2015, Qualcomm Atheros, Inc.
  6. *
  7. * Rewrite: Copyright (C) 2013 Linaro Ltd <ard.biesheuvel@linaro.org>
  8. */
  9. #include <linux/kernel.h>
  10. #include <linux/types.h>
  11. #include <linux/err.h>
  12. #include <linux/scatterlist.h>
  13. #include <crypto/aead.h>
  14. #include "aead_api.h"
  15. int aead_encrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad, size_t aad_len,
  16. u8 *data, size_t data_len, u8 *mic)
  17. {
  18. size_t mic_len = crypto_aead_authsize(tfm);
  19. struct scatterlist sg[3];
  20. struct aead_request *aead_req;
  21. int reqsize = sizeof(*aead_req) + crypto_aead_reqsize(tfm);
  22. u8 *__aad;
  23. int ret;
  24. aead_req = kzalloc(reqsize + aad_len, GFP_ATOMIC);
  25. if (!aead_req)
  26. return -ENOMEM;
  27. __aad = (u8 *)aead_req + reqsize;
  28. memcpy(__aad, aad, aad_len);
  29. sg_init_table(sg, 3);
  30. sg_set_buf(&sg[0], __aad, aad_len);
  31. sg_set_buf(&sg[1], data, data_len);
  32. sg_set_buf(&sg[2], mic, mic_len);
  33. aead_request_set_tfm(aead_req, tfm);
  34. aead_request_set_crypt(aead_req, sg, sg, data_len, b_0);
  35. aead_request_set_ad(aead_req, sg[0].length);
  36. ret = crypto_aead_encrypt(aead_req);
  37. kfree_sensitive(aead_req);
  38. return ret;
  39. }
  40. int aead_decrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad, size_t aad_len,
  41. u8 *data, size_t data_len, u8 *mic)
  42. {
  43. size_t mic_len = crypto_aead_authsize(tfm);
  44. struct scatterlist sg[3];
  45. struct aead_request *aead_req;
  46. int reqsize = sizeof(*aead_req) + crypto_aead_reqsize(tfm);
  47. u8 *__aad;
  48. int err;
  49. if (data_len == 0)
  50. return -EINVAL;
  51. aead_req = kzalloc(reqsize + aad_len, GFP_ATOMIC);
  52. if (!aead_req)
  53. return -ENOMEM;
  54. __aad = (u8 *)aead_req + reqsize;
  55. memcpy(__aad, aad, aad_len);
  56. sg_init_table(sg, 3);
  57. sg_set_buf(&sg[0], __aad, aad_len);
  58. sg_set_buf(&sg[1], data, data_len);
  59. sg_set_buf(&sg[2], mic, mic_len);
  60. aead_request_set_tfm(aead_req, tfm);
  61. aead_request_set_crypt(aead_req, sg, sg, data_len + mic_len, b_0);
  62. aead_request_set_ad(aead_req, sg[0].length);
  63. err = crypto_aead_decrypt(aead_req);
  64. kfree_sensitive(aead_req);
  65. return err;
  66. }
  67. struct crypto_aead *
  68. aead_key_setup_encrypt(const char *alg, const u8 key[],
  69. size_t key_len, size_t mic_len)
  70. {
  71. struct crypto_aead *tfm;
  72. int err;
  73. tfm = crypto_alloc_aead(alg, 0, CRYPTO_ALG_ASYNC);
  74. if (IS_ERR(tfm))
  75. return tfm;
  76. err = crypto_aead_setkey(tfm, key, key_len);
  77. if (err)
  78. goto free_aead;
  79. err = crypto_aead_setauthsize(tfm, mic_len);
  80. if (err)
  81. goto free_aead;
  82. return tfm;
  83. free_aead:
  84. crypto_free_aead(tfm);
  85. return ERR_PTR(err);
  86. }
  87. void aead_key_free(struct crypto_aead *tfm)
  88. {
  89. crypto_free_aead(tfm);
  90. }