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Diffstat (limited to 'fs/verity/Kconfig')
| -rw-r--r-- | fs/verity/Kconfig | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/fs/verity/Kconfig b/fs/verity/Kconfig new file mode 100644 index 000000000000..76d1c5971b82 --- /dev/null +++ b/fs/verity/Kconfig @@ -0,0 +1,46 @@ +# SPDX-License-Identifier: GPL-2.0 + +config FS_VERITY + bool "FS Verity (read-only file-based authenticity protection)" + select CRYPTO_HASH_INFO + select CRYPTO_LIB_SHA256 + select CRYPTO_LIB_SHA512 + help + This option enables fs-verity. fs-verity is the dm-verity + mechanism implemented at the file level. On supported + filesystems (currently ext4, f2fs, and btrfs), userspace can + use an ioctl to enable verity for a file, which causes the + filesystem to build a Merkle tree for the file. The filesystem + will then transparently verify any data read from the file + against the Merkle tree. The file is also made read-only. + + This serves as an integrity check, but the availability of the + Merkle tree root hash also allows efficiently supporting + various use cases where normally the whole file would need to + be hashed at once, such as: (a) auditing (logging the file's + hash), or (b) authenticity verification (comparing the hash + against a known good value, e.g. from a digital signature). + + fs-verity is especially useful on large files where not all + the contents may actually be needed. Also, fs-verity verifies + data each time it is paged back in, which provides better + protection against malicious disks vs. an ahead-of-time hash. + + If unsure, say N. + +config FS_VERITY_BUILTIN_SIGNATURES + bool "FS Verity builtin signature support" + depends on FS_VERITY + select SYSTEM_DATA_VERIFICATION + help + This option adds support for in-kernel verification of + fs-verity builtin signatures. + + Please take great care before using this feature. It is not + the only way to do signatures with fs-verity, and the + alternatives (such as userspace signature verification, and + IMA appraisal) can be much better. For details about the + limitations of this feature, see + Documentation/filesystems/fsverity.rst. + + If unsure, say N. |
