keys: allow clients to set key perms in key_create_or_update()

The key_create_or_update() function provided by the keyring code has a default
set of permissions that are always applied to the key when created.  This
might not be desirable to all clients.

Here's a patch that adds a "perm" parameter to the function to address this,
which can be set to KEY_PERM_UNDEF to revert to the current behaviour.

Signed-off-by: Arun Raghavan <arunsr@cse.iitk.ac.in>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Satyam Sharma <ssatyam@cse.iitk.ac.in>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Arun Raghavan 2008-04-29 01:01:28 -07:00 коммит произвёл Linus Torvalds
Родитель da91d2ef9f
Коммит 6b79ccb514
3 изменённых файлов: 15 добавлений и 9 удалений

Просмотреть файл

@ -67,6 +67,8 @@ struct key;
#define KEY_OTH_SETATTR 0x00000020
#define KEY_OTH_ALL 0x0000003f
#define KEY_PERM_UNDEF 0xffffffff
struct seq_file;
struct user_struct;
struct signal_struct;
@ -232,6 +234,7 @@ extern key_ref_t key_create_or_update(key_ref_t keyring,
const char *description,
const void *payload,
size_t plen,
key_perm_t perm,
unsigned long flags);
extern int key_update(key_ref_t key,

Просмотреть файл

@ -757,11 +757,11 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
const char *description,
const void *payload,
size_t plen,
key_perm_t perm,
unsigned long flags)
{
struct key_type *ktype;
struct key *keyring, *key = NULL;
key_perm_t perm;
key_ref_t key_ref;
int ret;
@ -806,15 +806,17 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
goto found_matching_key;
}
/* decide on the permissions we want */
perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK | KEY_POS_SETATTR;
perm |= KEY_USR_VIEW | KEY_USR_SEARCH | KEY_USR_LINK | KEY_USR_SETATTR;
/* if the client doesn't provide, decide on the permissions we want */
if (perm == KEY_PERM_UNDEF) {
perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK | KEY_POS_SETATTR;
perm |= KEY_USR_VIEW | KEY_USR_SEARCH | KEY_USR_LINK | KEY_USR_SETATTR;
if (ktype->read)
perm |= KEY_POS_READ | KEY_USR_READ;
if (ktype->read)
perm |= KEY_POS_READ | KEY_USR_READ;
if (ktype == &key_type_keyring || ktype->update)
perm |= KEY_USR_WRITE;
if (ktype == &key_type_keyring || ktype->update)
perm |= KEY_USR_WRITE;
}
/* allocate a new key */
key = key_alloc(ktype, description, current->fsuid, current->fsgid,

Просмотреть файл

@ -112,7 +112,8 @@ asmlinkage long sys_add_key(const char __user *_type,
/* create or update the requested key and add it to the target
* keyring */
key_ref = key_create_or_update(keyring_ref, type, description,
payload, plen, KEY_ALLOC_IN_QUOTA);
payload, plen, KEY_PERM_UNDEF,
KEY_ALLOC_IN_QUOTA);
if (!IS_ERR(key_ref)) {
ret = key_ref_to_ptr(key_ref)->serial;
key_ref_put(key_ref);