diff options
Diffstat (limited to '')
| -rw-r--r-- | security/keys/keyctl.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index 52c34532c785..6ee2826a2d06 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -1583,6 +1583,59 @@ error_keyring: } /* + * Apply a restriction to a given keyring. + * + * The caller must have Setattr permission to change keyring restrictions. + * + * The requested type name may be a NULL pointer to reject all attempts + * to link to the keyring. If _type is non-NULL, _restriction can be + * NULL or a pointer to a string describing the restriction. If _type is + * NULL, _restriction must also be NULL. + * + * Returns 0 if successful. + */ +long keyctl_restrict_keyring(key_serial_t id, const char __user *_type, + const char __user *_restriction) +{ + key_ref_t key_ref; + bool link_reject = !_type; + char type[32]; + char *restriction = NULL; + long ret; + + key_ref = lookup_user_key(id, 0, KEY_NEED_SETATTR); + if (IS_ERR(key_ref)) + return PTR_ERR(key_ref); + + if (_type) { + ret = key_get_type_from_user(type, _type, sizeof(type)); + if (ret < 0) + goto error; + } + + if (_restriction) { + if (!_type) { + ret = -EINVAL; + goto error; + } + + restriction = strndup_user(_restriction, PAGE_SIZE); + if (IS_ERR(restriction)) { + ret = PTR_ERR(restriction); + goto error; + } + } + + ret = keyring_restrict(key_ref, link_reject ? NULL : type, restriction); + kfree(restriction); + +error: + key_ref_put(key_ref); + + return ret; +} + +/* * The key control system call */ SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3, @@ -1693,6 +1746,11 @@ SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3, (char __user *) arg3, (size_t) arg4, (void __user *) arg5); + case KEYCTL_RESTRICT_KEYRING: + return keyctl_restrict_keyring((key_serial_t) arg2, + (const char __user *) arg3, + (const char __user *) arg4); + default: return -EOPNOTSUPP; } |