1# 2# Key management configuration 3# 4 5config KEYS 6 bool "Enable access key retention support" 7 select ASSOCIATIVE_ARRAY 8 help 9 This option provides support for retaining authentication tokens and 10 access keys in the kernel. 11 12 It also includes provision of methods by which such keys might be 13 associated with a process so that network filesystems, encryption 14 support and the like can find them. 15 16 Furthermore, a special type of key is available that acts as keyring: 17 a searchable sequence of keys. Each process is equipped with access 18 to five standard keyrings: UID-specific, GID-specific, session, 19 process and thread. 20 21 If you are unsure as to whether this is required, answer N. 22 23config BIG_KEYS 24 tristate "Large payload keys" 25 depends on KEYS 26 depends on TMPFS 27 help 28 This option provides support for holding large keys within the kernel 29 (for example Kerberos ticket caches). The data may be stored out to 30 swapspace by tmpfs. 31 32 If you are unsure as to whether this is required, answer N. 33 34config TRUSTED_KEYS 35 tristate "TRUSTED KEYS" 36 depends on KEYS && TCG_TPM 37 select CRYPTO 38 select CRYPTO_HMAC 39 select CRYPTO_SHA1 40 help 41 This option provides support for creating, sealing, and unsealing 42 keys in the kernel. Trusted keys are random number symmetric keys, 43 generated and RSA-sealed by the TPM. The TPM only unseals the keys, 44 if the boot PCRs and other criteria match. Userspace will only ever 45 see encrypted blobs. 46 47 If you are unsure as to whether this is required, answer N. 48 49config ENCRYPTED_KEYS 50 tristate "ENCRYPTED KEYS" 51 depends on KEYS 52 select CRYPTO 53 select CRYPTO_HMAC 54 select CRYPTO_AES 55 select CRYPTO_CBC 56 select CRYPTO_SHA256 57 select CRYPTO_RNG 58 help 59 This option provides support for create/encrypting/decrypting keys 60 in the kernel. Encrypted keys are kernel generated random numbers, 61 which are encrypted/decrypted with a 'master' symmetric key. The 62 'master' key can be either a trusted-key or user-key type. 63 Userspace only ever sees/stores encrypted blobs. 64 65 If you are unsure as to whether this is required, answer N. 66 67config KEYS_DEBUG_PROC_KEYS 68 bool "Enable the /proc/keys file by which keys may be viewed" 69 depends on KEYS 70 help 71 This option turns on support for the /proc/keys file - through which 72 can be listed all the keys on the system that are viewable by the 73 reading process. 74 75 The only keys included in the list are those that grant View 76 permission to the reading process whether or not it possesses them. 77 Note that LSM security checks are still performed, and may further 78 filter out keys that the current process is not authorised to view. 79 80 Only key attributes are listed here; key payloads are not included in 81 the resulting table. 82 83 If you are unsure as to whether this is required, answer N. 84