path: root/security/keys/Makefile
diff options
authorDavid Howells <>2005-06-23 22:00:56 -0700
committerLinus Torvalds <>2005-06-24 00:05:19 -0700
commit3e30148c3d524a9c1c63ca28261bc24c457eb07a (patch)
treea2fcc46cc11fe871ad976c07476d934a07313576 /security/keys/Makefile
parent8589b4e00e352f983259140f25a262d973be6bc5 (diff)
[PATCH] Keys: Make request-key create an authorisation key
The attached patch makes the following changes: (1) There's a new special key type called ".request_key_auth". This is an authorisation key for when one process requests a key and another process is started to construct it. This type of key cannot be created by the user; nor can it be requested by kernel services. Authorisation keys hold two references: (a) Each refers to a key being constructed. When the key being constructed is instantiated the authorisation key is revoked, rendering it of no further use. (b) The "authorising process". This is either: (i) the process that called request_key(), or: (ii) if the process that called request_key() itself had an authorisation key in its session keyring, then the authorising process referred to by that authorisation key will also be referred to by the new authorisation key. This means that the process that initiated a chain of key requests will authorise the lot of them, and will, by default, wind up with the keys obtained from them in its keyrings. (2) request_key() creates an authorisation key which is then passed to /sbin/request-key in as part of a new session keyring. (3) When request_key() is searching for a key to hand back to the caller, if it comes across an authorisation key in the session keyring of the calling process, it will also search the keyrings of the process specified therein and it will use the specified process's credentials (fsuid, fsgid, groups) to do that rather than the calling process's credentials. This allows a process started by /sbin/request-key to find keys belonging to the authorising process. (4) A key can be read, even if the process executing KEYCTL_READ doesn't have direct read or search permission if that key is contained within the keyrings of a process specified by an authorisation key found within the calling process's session keyring, and is searchable using the credentials of the authorising process. This allows a process started by /sbin/request-key to read keys belonging to the authorising process. (5) The magic KEY_SPEC_*_KEYRING key IDs when passed to KEYCTL_INSTANTIATE or KEYCTL_NEGATE will specify a keyring of the authorising process, rather than the process doing the instantiation. (6) One of the process keyrings can be nominated as the default to which request_key() should attach new keys if not otherwise specified. This is done with KEYCTL_SET_REQKEY_KEYRING and one of the KEY_REQKEY_DEFL_* constants. The current setting can also be read using this call. (7) request_key() is partially interruptible. If it is waiting for another process to finish constructing a key, it can be interrupted. This permits a request-key cycle to be broken without recourse to rebooting. Signed-Off-By: David Howells <> Signed-Off-By: Benoit Boissinot <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
Diffstat (limited to 'security/keys/Makefile')
1 files changed, 3 insertions, 2 deletions
diff --git a/security/keys/Makefile b/security/keys/Makefile
index ddb495d65062..c392d750b208 100644
--- a/security/keys/Makefile
+++ b/security/keys/Makefile
@@ -7,8 +7,9 @@ obj-y := \
keyring.o \
keyctl.o \
process_keys.o \
- user_defined.o \
- request_key.o
+ request_key.o \
+ request_key_auth.o \
+ user_defined.o
obj-$(CONFIG_KEYS_COMPAT) += compat.o
obj-$(CONFIG_PROC_FS) += proc.o