security/keys/Kconfig

Source file repositories/reference/linux-study-clean/security/keys/Kconfig

File Facts

System
Linux kernel
Corpus path
security/keys/Kconfig
Extension
[no extension]
Size
4712 bytes
Lines
132
Domain
Core OS
Bucket
Security And Isolation
Inferred role
Core OS: build/configuration rule
Status
atlas-only

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

# SPDX-License-Identifier: GPL-2.0-only
#
# Key management configuration
#

menuconfig KEYS
	bool "Enable access key retention support"
	select ASSOCIATIVE_ARRAY
	help
	  This option provides support for retaining authentication tokens and
	  access keys in the kernel.

	  It also includes provision of methods by which such keys might be
	  associated with a process so that network filesystems, encryption
	  support and the like can find them.

	  Furthermore, a special type of key is available that acts as keyring:
	  a searchable sequence of keys. Each process is equipped with access
	  to five standard keyrings: UID-specific, GID-specific, session,
	  process and thread.

	  If you are unsure as to whether this is required, answer N.

if KEYS

config KEYS_REQUEST_CACHE
	bool "Enable temporary caching of the last request_key() result"
	help
	  This option causes the result of the last successful request_key()
	  call that didn't upcall to the kernel to be cached temporarily in the
	  task_struct.  The cache is cleared by exit and just prior to the
	  resumption of userspace.

	  This allows the key used for multiple step processes where each step
	  wants to request a key that is likely the same as the one requested
	  by the last step to save on the searching.

	  An example of such a process is a pathwalk through a network
	  filesystem in which each method needs to request an authentication
	  key.  Pathwalk will call multiple methods for each dentry traversed
	  (permission, d_revalidate, lookup, getxattr, getacl, ...).

config PERSISTENT_KEYRINGS
	bool "Enable register of persistent per-UID keyrings"
	help
	  This option provides a register of persistent per-UID keyrings,
	  primarily aimed at Kerberos key storage.  The keyrings are persistent
	  in the sense that they stay around after all processes of that UID
	  have exited, not that they survive the machine being rebooted.

	  A particular keyring may be accessed by either the user whose keyring
	  it is or by a process with administrative privileges.  The active
	  LSMs gets to rule on which admin-level processes get to access the
	  cache.

	  Keyrings are created and added into the register upon demand and get
	  removed if they expire (a default timeout is set upon creation).

config BIG_KEYS
	bool "Large payload keys"
	depends on TMPFS
	select CRYPTO_LIB_CHACHA20POLY1305
	help
	  This option provides support for holding large keys within the kernel
	  (for example Kerberos ticket caches).  The data may be stored out to
	  swapspace by tmpfs.

	  If you are unsure as to whether this is required, answer N.

config TRUSTED_KEYS

Annotation

Implementation Notes