#include <linux/syscalls.h>
#include <linux/keyctl.h>
#include <linux/fs.h>
+#include <linux/capability.h>
#include <linux/err.h>
#include <asm/uaccess.h>
#include "internal.h"
/* link the resulting key to the destination keyring if we can */
if (dest_ref) {
- ret = -EACCES;
- if (!key_permission(key_ref, KEY_LINK))
+ ret = key_permission(key_ref, KEY_LINK);
+ if (ret < 0)
goto error6;
ret = key_link(key_ref_to_ptr(dest_ref), key_ref_to_ptr(key_ref));
key = key_ref_to_ptr(key_ref);
/* see if we can read it directly */
- if (key_permission(key_ref, KEY_READ))
+ ret = key_permission(key_ref, KEY_READ);
+ if (ret == 0)
goto can_read_key;
+ if (ret != -EACCES)
+ goto error;
/* we can't; see if it's searchable from this process's keyrings
* - we automatically take account of the fact that it may be
if (uid == (uid_t) -1 && gid == (gid_t) -1)
goto error;
- key_ref = lookup_user_key(NULL, id, 1, 1, 0);
+ key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR);
if (IS_ERR(key_ref)) {
ret = PTR_ERR(key_ref);
goto error;
if (perm & ~(KEY_POS_ALL | KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL))
goto error;
- key_ref = lookup_user_key(NULL, id, 1, 1, 0);
+ key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR);
if (IS_ERR(key_ref)) {
ret = PTR_ERR(key_ref);
goto error;
if (plen > 32767)
goto error;
+ /* the appropriate instantiation authorisation key must have been
+ * assumed before calling this */
+ ret = -EPERM;
+ instkey = current->request_key_auth;
+ if (!instkey)
+ goto error;
+
+ rka = instkey->payload.data;
+ if (rka->target_key->serial != id)
+ goto error;
+
/* pull the payload in if one was supplied */
payload = NULL;
goto error2;
}
- /* find the instantiation authorisation key */
- instkey = key_get_instantiation_authkey(id);
- if (IS_ERR(instkey)) {
- ret = PTR_ERR(instkey);
- goto error2;
- }
-
- rka = instkey->payload.data;
-
/* find the destination keyring amongst those belonging to the
* requesting task */
keyring_ref = NULL;
KEY_WRITE);
if (IS_ERR(keyring_ref)) {
ret = PTR_ERR(keyring_ref);
- goto error3;
+ goto error2;
}
}
key_ref_to_ptr(keyring_ref), instkey);
key_ref_put(keyring_ref);
- error3:
- key_put(instkey);
- error2:
+
+ /* discard the assumed authority if it's just been disabled by
+ * instantiation of the key */
+ if (ret == 0) {
+ key_put(current->request_key_auth);
+ current->request_key_auth = NULL;
+ }
+
+error2:
kfree(payload);
- error:
+error:
return ret;
} /* end keyctl_instantiate_key() */
key_ref_t keyring_ref;
long ret;
- /* find the instantiation authorisation key */
- instkey = key_get_instantiation_authkey(id);
- if (IS_ERR(instkey)) {
- ret = PTR_ERR(instkey);
+ /* the appropriate instantiation authorisation key must have been
+ * assumed before calling this */
+ ret = -EPERM;
+ instkey = current->request_key_auth;
+ if (!instkey)
goto error;
- }
rka = instkey->payload.data;
+ if (rka->target_key->serial != id)
+ goto error;
/* find the destination keyring if present (which must also be
* writable) */
keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
if (IS_ERR(keyring_ref)) {
ret = PTR_ERR(keyring_ref);
- goto error2;
+ goto error;
}
}
key_ref_to_ptr(keyring_ref), instkey);
key_ref_put(keyring_ref);
- error2:
- key_put(instkey);
- error:
+
+ /* discard the assumed authority if it's just been disabled by
+ * instantiation of the key */
+ if (ret == 0) {
+ key_put(current->request_key_auth);
+ current->request_key_auth = NULL;
+ }
+
+error:
return ret;
} /* end keyctl_negate_key() */
} /* end keyctl_set_reqkey_keyring() */
+/*****************************************************************************/
+/*
+ * set or clear the timeout for a key
+ */
+long keyctl_set_timeout(key_serial_t id, unsigned timeout)
+{
+ struct timespec now;
+ struct key *key;
+ key_ref_t key_ref;
+ time_t expiry;
+ long ret;
+
+ key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR);
+ if (IS_ERR(key_ref)) {
+ ret = PTR_ERR(key_ref);
+ goto error;
+ }
+
+ key = key_ref_to_ptr(key_ref);
+
+ /* make the changes with the locks held to prevent races */
+ down_write(&key->sem);
+
+ expiry = 0;
+ if (timeout > 0) {
+ now = current_kernel_time();
+ expiry = now.tv_sec + timeout;
+ }
+
+ key->expiry = expiry;
+
+ up_write(&key->sem);
+ key_put(key);
+
+ ret = 0;
+error:
+ return ret;
+
+} /* end keyctl_set_timeout() */
+
+/*****************************************************************************/
+/*
+ * assume the authority to instantiate the specified key
+ */
+long keyctl_assume_authority(key_serial_t id)
+{
+ struct key *authkey;
+ long ret;
+
+ /* special key IDs aren't permitted */
+ ret = -EINVAL;
+ if (id < 0)
+ goto error;
+
+ /* we divest ourselves of authority if given an ID of 0 */
+ if (id == 0) {
+ key_put(current->request_key_auth);
+ current->request_key_auth = NULL;
+ ret = 0;
+ goto error;
+ }
+
+ /* attempt to assume the authority temporarily granted to us whilst we
+ * instantiate the specified key
+ * - the authorisation key must be in the current task's keyrings
+ * somewhere
+ */
+ authkey = key_get_instantiation_authkey(id);
+ if (IS_ERR(authkey)) {
+ ret = PTR_ERR(authkey);
+ goto error;
+ }
+
+ key_put(current->request_key_auth);
+ current->request_key_auth = authkey;
+ ret = authkey->serial;
+
+error:
+ return ret;
+
+} /* end keyctl_assume_authority() */
+
/*****************************************************************************/
/*
* the key control system call
case KEYCTL_SET_REQKEY_KEYRING:
return keyctl_set_reqkey_keyring(arg2);
+ case KEYCTL_SET_TIMEOUT:
+ return keyctl_set_timeout((key_serial_t) arg2,
+ (unsigned) arg3);
+
+ case KEYCTL_ASSUME_AUTHORITY:
+ return keyctl_assume_authority((key_serial_t) arg2);
+
default:
return -EOPNOTSUPP;
}
Code Review / linux-2.6.git / blobdiff