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Diffstat (limited to 'Documentation/keys.txt')
-rw-r--r-- | Documentation/keys.txt | 61 |
1 files changed, 42 insertions, 19 deletions
diff --git a/Documentation/keys.txt b/Documentation/keys.txt index 31154882000a..aaa01b0e3ee9 100644 --- a/Documentation/keys.txt +++ b/Documentation/keys.txt @@ -308,6 +308,8 @@ process making the call: KEY_SPEC_USER_KEYRING -4 UID-specific keyring KEY_SPEC_USER_SESSION_KEYRING -5 UID-session keyring KEY_SPEC_GROUP_KEYRING -6 GID-specific keyring + KEY_SPEC_REQKEY_AUTH_KEY -7 assumed request_key() + authorisation key The main syscalls are: @@ -498,7 +500,11 @@ The keyctl syscall functions are: keyring is full, error ENFILE will result. The link procedure checks the nesting of the keyrings, returning ELOOP if - it appears to deep or EDEADLK if the link would introduce a cycle. + it appears too deep or EDEADLK if the link would introduce a cycle. + + Any links within the keyring to keys that match the new key in terms of + type and description will be discarded from the keyring as the new one is + added. (*) Unlink a key or keyring from another keyring: @@ -628,6 +634,41 @@ The keyctl syscall functions are: there is one, otherwise the user default session keyring. + (*) Set the timeout on a key. + + long keyctl(KEYCTL_SET_TIMEOUT, key_serial_t key, unsigned timeout); + + This sets or clears the timeout on a key. The timeout can be 0 to clear + the timeout or a number of seconds to set the expiry time that far into + the future. + + The process must have attribute modification access on a key to set its + timeout. Timeouts may not be set with this function on negative, revoked + or expired keys. + + + (*) Assume the authority granted to instantiate a key + + long keyctl(KEYCTL_ASSUME_AUTHORITY, key_serial_t key); + + This assumes or divests the authority required to instantiate the + specified key. Authority can only be assumed if the thread has the + authorisation key associated with the specified key in its keyrings + somewhere. + + Once authority is assumed, searches for keys will also search the + requester's keyrings using the requester's security label, UID, GID and + groups. + + If the requested authority is unavailable, error EPERM will be returned, + likewise if the authority has been revoked because the target key is + already instantiated. + + If the specified key is 0, then any assumed authority will be divested. + + The assumed authorititive key is inherited across fork and exec. + + =============== KERNEL SERVICES =============== @@ -860,24 +901,6 @@ The structure has a number of fields, some of which are mandatory: It is safe to sleep in this method. - (*) int (*duplicate)(struct key *key, const struct key *source); - - If this type of key can be duplicated, then this method should be - provided. It is called to copy the payload attached to the source into the - new key. The data length on the new key will have been updated and the - quota adjusted already. - - This method will be called with the source key's semaphore read-locked to - prevent its payload from being changed, thus RCU constraints need not be - applied to the source key. - - This method does not have to lock the destination key in order to attach a - payload. The fact that KEY_FLAG_INSTANTIATED is not set in key->flags - prevents anything else from gaining access to the key. - - It is safe to sleep in this method. - - (*) int (*update)(struct key *key, const void *data, size_t datalen); If this type of key can be updated, then this method should be provided. |