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oasis-root

Compiled tree of Oasis Linux based on own branch at <https://hacktivis.me/git/oasis/> git clone https://anongit.hacktivis.me/git/oasis-root.git

fsverity.h (3185B)

    

  1. /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
  2. /*
  3.  * fs-verity user API
  4.  *
  5.  * These ioctls can be used on filesystems that support fs-verity.  See the
  6.  * "User API" section of Documentation/filesystems/fsverity.rst.
  7.  *
  8.  * Copyright 2019 Google LLC
  9.  */
  10. #ifndef _LINUX_FSVERITY_H
  11. #define _LINUX_FSVERITY_H
  13. #include <linux/ioctl.h>
  14. #include <linux/types.h>
  16. #define FS_VERITY_HASH_ALG_SHA256	1
  17. #define FS_VERITY_HASH_ALG_SHA512	2
  19. struct fsverity_enable_arg {
  20. 	__u32 version;
  21. 	__u32 hash_algorithm;
  22. 	__u32 block_size;
  23. 	__u32 salt_size;
  24. 	__u64 salt_ptr;
  25. 	__u32 sig_size;
  26. 	__u32 __reserved1;
  27. 	__u64 sig_ptr;
  28. 	__u64 __reserved2[11];
  29. };
  31. struct fsverity_digest {
  32. 	__u16 digest_algorithm;
  33. 	__u16 digest_size; /* input/output */
  34. 	__u8 digest[];
  35. };
  37. /*
  38.  * Struct containing a file's Merkle tree properties.  The fs-verity file digest
  39.  * is the hash of this struct.  A userspace program needs this struct only if it
  40.  * needs to compute fs-verity file digests itself, e.g. in order to sign files.
  41.  * It isn't needed just to enable fs-verity on a file.
  42.  *
  43.  * Note: when computing the file digest, 'sig_size' and 'signature' must be left
  44.  * zero and empty, respectively.  These fields are present only because some
  45.  * filesystems reuse this struct as part of their on-disk format.
  46.  */
  47. struct fsverity_descriptor {
  48. 	__u8 version;		/* must be 1 */
  49. 	__u8 hash_algorithm;	/* Merkle tree hash algorithm */
  50. 	__u8 log_blocksize;	/* log2 of size of data and tree blocks */
  51. 	__u8 salt_size;		/* size of salt in bytes; 0 if none */
  52. 	__le32 __reserved_0x04;	/* must be 0 */
  53. 	__le64 data_size;	/* size of file the Merkle tree is built over */
  54. 	__u8 root_hash[64];	/* Merkle tree root hash */
  55. 	__u8 salt[32];		/* salt prepended to each hashed block */
  56. 	__u8 __reserved[144];	/* must be 0's */
  57. };
  59. /*
  60.  * Format in which fs-verity file digests are signed in built-in signatures.
  61.  * This is the same as 'struct fsverity_digest', except here some magic bytes
  62.  * are prepended to provide some context about what is being signed in case the
  63.  * same key is used for non-fsverity purposes, and here the fields have fixed
  64.  * endianness.
  65.  *
  66.  * This struct is specific to the built-in signature verification support, which
  67.  * is optional.  fs-verity users may also verify signatures in userspace, in
  68.  * which case userspace is responsible for deciding on what bytes are signed.
  69.  * This struct may still be used, but it doesn't have to be.  For example,
  70.  * userspace could instead use a string like "sha256:$digest_as_hex_string".
  71.  */
  72. struct fsverity_formatted_digest {
  73. 	char magic[8];			/* must be "FSVerity" */
  74. 	__le16 digest_algorithm;
  75. 	__le16 digest_size;
  76. 	__u8 digest[];
  77. };
  79. #define FS_VERITY_METADATA_TYPE_MERKLE_TREE	1
  80. #define FS_VERITY_METADATA_TYPE_DESCRIPTOR	2
  81. #define FS_VERITY_METADATA_TYPE_SIGNATURE	3
  83. struct fsverity_read_metadata_arg {
  84. 	__u64 metadata_type;
  85. 	__u64 offset;
  86. 	__u64 length;
  87. 	__u64 buf_ptr;
  88. 	__u64 __reserved;
  89. };
  91. #define FS_IOC_ENABLE_VERITY	_IOW('f', 133, struct fsverity_enable_arg)
  92. #define FS_IOC_MEASURE_VERITY	_IOWR('f', 134, struct fsverity_digest)
  93. #define FS_IOC_READ_VERITY_METADATA \
  94. 	_IOWR('f', 135, struct fsverity_read_metadata_arg)
  96. #endif /* _LINUX_FSVERITY_H */