1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
988 lines
22 KiB
C
988 lines
22 KiB
C
/* keyctl.c: userspace keyctl operations
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*
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* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/syscalls.h>
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#include <linux/keyctl.h>
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#include <linux/fs.h>
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#include <linux/err.h>
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#include <asm/uaccess.h>
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#include "internal.h"
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/*****************************************************************************/
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/*
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* extract the description of a new key from userspace and either add it as a
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* new key to the specified keyring or update a matching key in that keyring
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* - the keyring must be writable
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* - returns the new key's serial number
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* - implements add_key()
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*/
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asmlinkage long sys_add_key(const char __user *_type,
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const char __user *_description,
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const void __user *_payload,
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size_t plen,
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key_serial_t ringid)
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{
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struct key *keyring, *key;
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char type[32], *description;
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void *payload;
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long dlen, ret;
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ret = -EINVAL;
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if (plen > 32767)
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goto error;
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/* draw all the data into kernel space */
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ret = strncpy_from_user(type, _type, sizeof(type) - 1);
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if (ret < 0)
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goto error;
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type[31] = '\0';
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ret = -EFAULT;
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dlen = strnlen_user(_description, PAGE_SIZE - 1);
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if (dlen <= 0)
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goto error;
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ret = -EINVAL;
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if (dlen > PAGE_SIZE - 1)
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goto error;
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ret = -ENOMEM;
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description = kmalloc(dlen + 1, GFP_KERNEL);
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if (!description)
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goto error;
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ret = -EFAULT;
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if (copy_from_user(description, _description, dlen + 1) != 0)
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goto error2;
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/* pull the payload in if one was supplied */
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payload = NULL;
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if (_payload) {
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ret = -ENOMEM;
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payload = kmalloc(plen, GFP_KERNEL);
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if (!payload)
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goto error2;
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ret = -EFAULT;
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if (copy_from_user(payload, _payload, plen) != 0)
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goto error3;
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}
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/* find the target keyring (which must be writable) */
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keyring = lookup_user_key(ringid, 1, 0, KEY_WRITE);
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if (IS_ERR(keyring)) {
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ret = PTR_ERR(keyring);
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goto error3;
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}
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/* create or update the requested key and add it to the target
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* keyring */
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key = key_create_or_update(keyring, type, description,
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payload, plen, 0);
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if (!IS_ERR(key)) {
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ret = key->serial;
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key_put(key);
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}
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else {
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ret = PTR_ERR(key);
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}
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key_put(keyring);
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error3:
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kfree(payload);
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error2:
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kfree(description);
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error:
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return ret;
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} /* end sys_add_key() */
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/*****************************************************************************/
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/*
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* search the process keyrings for a matching key
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* - nested keyrings may also be searched if they have Search permission
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* - if a key is found, it will be attached to the destination keyring if
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* there's one specified
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* - /sbin/request-key will be invoked if _callout_info is non-NULL
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* - the _callout_info string will be passed to /sbin/request-key
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* - if the _callout_info string is empty, it will be rendered as "-"
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* - implements request_key()
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*/
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asmlinkage long sys_request_key(const char __user *_type,
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const char __user *_description,
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const char __user *_callout_info,
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key_serial_t destringid)
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{
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struct key_type *ktype;
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struct key *key, *dest;
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char type[32], *description, *callout_info;
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long dlen, ret;
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/* pull the type into kernel space */
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ret = strncpy_from_user(type, _type, sizeof(type) - 1);
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if (ret < 0)
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goto error;
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type[31] = '\0';
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/* pull the description into kernel space */
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ret = -EFAULT;
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dlen = strnlen_user(_description, PAGE_SIZE - 1);
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if (dlen <= 0)
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goto error;
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ret = -EINVAL;
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if (dlen > PAGE_SIZE - 1)
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goto error;
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ret = -ENOMEM;
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description = kmalloc(dlen + 1, GFP_KERNEL);
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if (!description)
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goto error;
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ret = -EFAULT;
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if (copy_from_user(description, _description, dlen + 1) != 0)
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goto error2;
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/* pull the callout info into kernel space */
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callout_info = NULL;
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if (_callout_info) {
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ret = -EFAULT;
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dlen = strnlen_user(_callout_info, PAGE_SIZE - 1);
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if (dlen <= 0)
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goto error2;
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ret = -EINVAL;
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if (dlen > PAGE_SIZE - 1)
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goto error2;
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ret = -ENOMEM;
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callout_info = kmalloc(dlen + 1, GFP_KERNEL);
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if (!callout_info)
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goto error2;
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ret = -EFAULT;
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if (copy_from_user(callout_info, _callout_info, dlen + 1) != 0)
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goto error3;
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}
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/* get the destination keyring if specified */
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dest = NULL;
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if (destringid) {
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dest = lookup_user_key(destringid, 1, 0, KEY_WRITE);
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if (IS_ERR(dest)) {
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ret = PTR_ERR(dest);
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goto error3;
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}
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}
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/* find the key type */
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ktype = key_type_lookup(type);
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if (IS_ERR(ktype)) {
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ret = PTR_ERR(ktype);
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goto error4;
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}
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/* do the search */
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key = request_key(ktype, description, callout_info);
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if (IS_ERR(key)) {
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ret = PTR_ERR(key);
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goto error5;
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}
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/* link the resulting key to the destination keyring */
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if (dest) {
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ret = key_link(dest, key);
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if (ret < 0)
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goto error6;
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}
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ret = key->serial;
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error6:
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key_put(key);
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error5:
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key_type_put(ktype);
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error4:
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key_put(dest);
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error3:
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kfree(callout_info);
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error2:
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kfree(description);
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error:
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return ret;
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} /* end sys_request_key() */
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/*****************************************************************************/
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/*
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* get the ID of the specified process keyring
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* - the keyring must have search permission to be found
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* - implements keyctl(KEYCTL_GET_KEYRING_ID)
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*/
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long keyctl_get_keyring_ID(key_serial_t id, int create)
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{
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struct key *key;
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long ret;
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key = lookup_user_key(id, create, 0, KEY_SEARCH);
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if (IS_ERR(key)) {
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ret = PTR_ERR(key);
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goto error;
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}
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ret = key->serial;
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key_put(key);
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error:
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return ret;
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} /* end keyctl_get_keyring_ID() */
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/*****************************************************************************/
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/*
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* join the session keyring
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* - implements keyctl(KEYCTL_JOIN_SESSION_KEYRING)
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*/
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long keyctl_join_session_keyring(const char __user *_name)
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{
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char *name;
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long nlen, ret;
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/* fetch the name from userspace */
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name = NULL;
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if (_name) {
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ret = -EFAULT;
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nlen = strnlen_user(_name, PAGE_SIZE - 1);
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if (nlen <= 0)
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goto error;
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ret = -EINVAL;
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if (nlen > PAGE_SIZE - 1)
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goto error;
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ret = -ENOMEM;
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name = kmalloc(nlen + 1, GFP_KERNEL);
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if (!name)
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goto error;
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ret = -EFAULT;
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if (copy_from_user(name, _name, nlen + 1) != 0)
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goto error2;
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}
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/* join the session */
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ret = join_session_keyring(name);
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error2:
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kfree(name);
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error:
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return ret;
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} /* end keyctl_join_session_keyring() */
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/*****************************************************************************/
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/*
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* update a key's data payload
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* - the key must be writable
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* - implements keyctl(KEYCTL_UPDATE)
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*/
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long keyctl_update_key(key_serial_t id,
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const void __user *_payload,
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size_t plen)
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{
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struct key *key;
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void *payload;
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long ret;
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ret = -EINVAL;
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if (plen > PAGE_SIZE)
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goto error;
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/* pull the payload in if one was supplied */
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payload = NULL;
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if (_payload) {
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ret = -ENOMEM;
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payload = kmalloc(plen, GFP_KERNEL);
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if (!payload)
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goto error;
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ret = -EFAULT;
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if (copy_from_user(payload, _payload, plen) != 0)
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goto error2;
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}
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/* find the target key (which must be writable) */
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key = lookup_user_key(id, 0, 0, KEY_WRITE);
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if (IS_ERR(key)) {
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ret = PTR_ERR(key);
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goto error2;
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}
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/* update the key */
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ret = key_update(key, payload, plen);
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key_put(key);
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error2:
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kfree(payload);
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error:
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return ret;
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} /* end keyctl_update_key() */
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/*****************************************************************************/
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/*
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* revoke a key
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* - the key must be writable
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* - implements keyctl(KEYCTL_REVOKE)
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*/
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long keyctl_revoke_key(key_serial_t id)
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{
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struct key *key;
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long ret;
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key = lookup_user_key(id, 0, 0, KEY_WRITE);
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if (IS_ERR(key)) {
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ret = PTR_ERR(key);
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goto error;
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}
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key_revoke(key);
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ret = 0;
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key_put(key);
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error:
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return 0;
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} /* end keyctl_revoke_key() */
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/*****************************************************************************/
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/*
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* clear the specified process keyring
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* - the keyring must be writable
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* - implements keyctl(KEYCTL_CLEAR)
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*/
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long keyctl_keyring_clear(key_serial_t ringid)
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{
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struct key *keyring;
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long ret;
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keyring = lookup_user_key(ringid, 1, 0, KEY_WRITE);
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if (IS_ERR(keyring)) {
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ret = PTR_ERR(keyring);
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goto error;
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}
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ret = keyring_clear(keyring);
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key_put(keyring);
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error:
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return ret;
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} /* end keyctl_keyring_clear() */
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/*****************************************************************************/
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/*
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* link a key into a keyring
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* - the keyring must be writable
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* - the key must be linkable
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* - implements keyctl(KEYCTL_LINK)
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*/
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long keyctl_keyring_link(key_serial_t id, key_serial_t ringid)
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{
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struct key *keyring, *key;
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long ret;
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keyring = lookup_user_key(ringid, 1, 0, KEY_WRITE);
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if (IS_ERR(keyring)) {
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ret = PTR_ERR(keyring);
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goto error;
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}
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key = lookup_user_key(id, 1, 0, KEY_LINK);
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if (IS_ERR(key)) {
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ret = PTR_ERR(key);
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goto error2;
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}
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ret = key_link(keyring, key);
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key_put(key);
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error2:
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key_put(keyring);
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error:
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return ret;
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} /* end keyctl_keyring_link() */
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/*****************************************************************************/
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/*
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* unlink the first attachment of a key from a keyring
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* - the keyring must be writable
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* - we don't need any permissions on the key
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* - implements keyctl(KEYCTL_UNLINK)
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*/
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long keyctl_keyring_unlink(key_serial_t id, key_serial_t ringid)
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{
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struct key *keyring, *key;
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long ret;
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keyring = lookup_user_key(ringid, 0, 0, KEY_WRITE);
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if (IS_ERR(keyring)) {
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ret = PTR_ERR(keyring);
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goto error;
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}
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key = lookup_user_key(id, 0, 0, 0);
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if (IS_ERR(key)) {
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ret = PTR_ERR(key);
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goto error2;
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}
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ret = key_unlink(keyring, key);
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key_put(key);
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error2:
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key_put(keyring);
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error:
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return ret;
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} /* end keyctl_keyring_unlink() */
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/*****************************************************************************/
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/*
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* describe a user key
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* - the key must have view permission
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* - if there's a buffer, we place up to buflen bytes of data into it
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* - unless there's an error, we return the amount of description available,
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* irrespective of how much we may have copied
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* - the description is formatted thus:
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* type;uid;gid;perm;description<NUL>
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* - implements keyctl(KEYCTL_DESCRIBE)
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*/
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long keyctl_describe_key(key_serial_t keyid,
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char __user *buffer,
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size_t buflen)
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{
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struct key *key;
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char *tmpbuf;
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long ret;
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key = lookup_user_key(keyid, 0, 1, KEY_VIEW);
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if (IS_ERR(key)) {
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ret = PTR_ERR(key);
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goto error;
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}
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/* calculate how much description we're going to return */
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ret = -ENOMEM;
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tmpbuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
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if (!tmpbuf)
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goto error2;
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ret = snprintf(tmpbuf, PAGE_SIZE - 1,
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"%s;%d;%d;%06x;%s",
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key->type->name,
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key->uid,
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key->gid,
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key->perm,
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key->description ? key->description :""
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);
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/* include a NUL char at the end of the data */
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if (ret > PAGE_SIZE - 1)
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ret = PAGE_SIZE - 1;
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tmpbuf[ret] = 0;
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ret++;
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/* consider returning the data */
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if (buffer && buflen > 0) {
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if (buflen > ret)
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buflen = ret;
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if (copy_to_user(buffer, tmpbuf, buflen) != 0)
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ret = -EFAULT;
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}
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kfree(tmpbuf);
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error2:
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key_put(key);
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error:
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return ret;
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} /* end keyctl_describe_key() */
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/*****************************************************************************/
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/*
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* search the specified keyring for a matching key
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* - the start keyring must be searchable
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|
* - nested keyrings may also be searched if they are searchable
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|
* - only keys with search permission may be found
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|
* - if a key is found, it will be attached to the destination keyring if
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* there's one specified
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* - implements keyctl(KEYCTL_SEARCH)
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*/
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long keyctl_keyring_search(key_serial_t ringid,
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const char __user *_type,
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const char __user *_description,
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key_serial_t destringid)
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{
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struct key_type *ktype;
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struct key *keyring, *key, *dest;
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char type[32], *description;
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long dlen, ret;
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|
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/* pull the type and description into kernel space */
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ret = strncpy_from_user(type, _type, sizeof(type) - 1);
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if (ret < 0)
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goto error;
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type[31] = '\0';
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ret = -EFAULT;
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dlen = strnlen_user(_description, PAGE_SIZE - 1);
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if (dlen <= 0)
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goto error;
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ret = -EINVAL;
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if (dlen > PAGE_SIZE - 1)
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goto error;
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ret = -ENOMEM;
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description = kmalloc(dlen + 1, GFP_KERNEL);
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if (!description)
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goto error;
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ret = -EFAULT;
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if (copy_from_user(description, _description, dlen + 1) != 0)
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goto error2;
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/* get the keyring at which to begin the search */
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keyring = lookup_user_key(ringid, 0, 0, KEY_SEARCH);
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if (IS_ERR(keyring)) {
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ret = PTR_ERR(keyring);
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goto error2;
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}
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|
|
|
/* get the destination keyring if specified */
|
|
dest = NULL;
|
|
if (destringid) {
|
|
dest = lookup_user_key(destringid, 1, 0, KEY_WRITE);
|
|
if (IS_ERR(dest)) {
|
|
ret = PTR_ERR(dest);
|
|
goto error3;
|
|
}
|
|
}
|
|
|
|
/* find the key type */
|
|
ktype = key_type_lookup(type);
|
|
if (IS_ERR(ktype)) {
|
|
ret = PTR_ERR(ktype);
|
|
goto error4;
|
|
}
|
|
|
|
/* do the search */
|
|
key = keyring_search(keyring, ktype, description);
|
|
if (IS_ERR(key)) {
|
|
ret = PTR_ERR(key);
|
|
|
|
/* treat lack or presence of a negative key the same */
|
|
if (ret == -EAGAIN)
|
|
ret = -ENOKEY;
|
|
goto error5;
|
|
}
|
|
|
|
/* link the resulting key to the destination keyring if we can */
|
|
if (dest) {
|
|
ret = -EACCES;
|
|
if (!key_permission(key, KEY_LINK))
|
|
goto error6;
|
|
|
|
ret = key_link(dest, key);
|
|
if (ret < 0)
|
|
goto error6;
|
|
}
|
|
|
|
ret = key->serial;
|
|
|
|
error6:
|
|
key_put(key);
|
|
error5:
|
|
key_type_put(ktype);
|
|
error4:
|
|
key_put(dest);
|
|
error3:
|
|
key_put(keyring);
|
|
error2:
|
|
kfree(description);
|
|
error:
|
|
return ret;
|
|
|
|
} /* end keyctl_keyring_search() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* see if the key we're looking at is the target key
|
|
*/
|
|
static int keyctl_read_key_same(const struct key *key, const void *target)
|
|
{
|
|
return key == target;
|
|
|
|
} /* end keyctl_read_key_same() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* read a user key's payload
|
|
* - the keyring must be readable or the key must be searchable from the
|
|
* process's keyrings
|
|
* - if there's a buffer, we place up to buflen bytes of data into it
|
|
* - unless there's an error, we return the amount of data in the key,
|
|
* irrespective of how much we may have copied
|
|
* - implements keyctl(KEYCTL_READ)
|
|
*/
|
|
long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen)
|
|
{
|
|
struct key *key, *skey;
|
|
long ret;
|
|
|
|
/* find the key first */
|
|
key = lookup_user_key(keyid, 0, 0, 0);
|
|
if (!IS_ERR(key)) {
|
|
/* see if we can read it directly */
|
|
if (key_permission(key, KEY_READ))
|
|
goto can_read_key;
|
|
|
|
/* can't; see if it's searchable from this process's
|
|
* keyrings */
|
|
ret = -ENOKEY;
|
|
if (key_permission(key, KEY_SEARCH)) {
|
|
/* okay - we do have search permission on the key
|
|
* itself, but do we have the key? */
|
|
skey = search_process_keyrings_aux(key->type, key,
|
|
keyctl_read_key_same);
|
|
if (!IS_ERR(skey))
|
|
goto can_read_key2;
|
|
}
|
|
|
|
goto error2;
|
|
}
|
|
|
|
ret = -ENOKEY;
|
|
goto error;
|
|
|
|
/* the key is probably readable - now try to read it */
|
|
can_read_key2:
|
|
key_put(skey);
|
|
can_read_key:
|
|
ret = key_validate(key);
|
|
if (ret == 0) {
|
|
ret = -EOPNOTSUPP;
|
|
if (key->type->read) {
|
|
/* read the data with the semaphore held (since we
|
|
* might sleep) */
|
|
down_read(&key->sem);
|
|
ret = key->type->read(key, buffer, buflen);
|
|
up_read(&key->sem);
|
|
}
|
|
}
|
|
|
|
error2:
|
|
key_put(key);
|
|
error:
|
|
return ret;
|
|
|
|
} /* end keyctl_read_key() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* change the ownership of a key
|
|
* - the keyring owned by the changer
|
|
* - if the uid or gid is -1, then that parameter is not changed
|
|
* - implements keyctl(KEYCTL_CHOWN)
|
|
*/
|
|
long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid)
|
|
{
|
|
struct key *key;
|
|
long ret;
|
|
|
|
ret = 0;
|
|
if (uid == (uid_t) -1 && gid == (gid_t) -1)
|
|
goto error;
|
|
|
|
key = lookup_user_key(id, 1, 1, 0);
|
|
if (IS_ERR(key)) {
|
|
ret = PTR_ERR(key);
|
|
goto error;
|
|
}
|
|
|
|
/* make the changes with the locks held to prevent chown/chown races */
|
|
ret = -EACCES;
|
|
down_write(&key->sem);
|
|
write_lock(&key->lock);
|
|
|
|
if (!capable(CAP_SYS_ADMIN)) {
|
|
/* only the sysadmin can chown a key to some other UID */
|
|
if (uid != (uid_t) -1 && key->uid != uid)
|
|
goto no_access;
|
|
|
|
/* only the sysadmin can set the key's GID to a group other
|
|
* than one of those that the current process subscribes to */
|
|
if (gid != (gid_t) -1 && gid != key->gid && !in_group_p(gid))
|
|
goto no_access;
|
|
}
|
|
|
|
/* change the UID (have to update the quotas) */
|
|
if (uid != (uid_t) -1 && uid != key->uid) {
|
|
/* don't support UID changing yet */
|
|
ret = -EOPNOTSUPP;
|
|
goto no_access;
|
|
}
|
|
|
|
/* change the GID */
|
|
if (gid != (gid_t) -1)
|
|
key->gid = gid;
|
|
|
|
ret = 0;
|
|
|
|
no_access:
|
|
write_unlock(&key->lock);
|
|
up_write(&key->sem);
|
|
key_put(key);
|
|
error:
|
|
return ret;
|
|
|
|
} /* end keyctl_chown_key() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* change the permission mask on a key
|
|
* - the keyring owned by the changer
|
|
* - implements keyctl(KEYCTL_SETPERM)
|
|
*/
|
|
long keyctl_setperm_key(key_serial_t id, key_perm_t perm)
|
|
{
|
|
struct key *key;
|
|
long ret;
|
|
|
|
ret = -EINVAL;
|
|
if (perm & ~(KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL))
|
|
goto error;
|
|
|
|
key = lookup_user_key(id, 1, 1, 0);
|
|
if (IS_ERR(key)) {
|
|
ret = PTR_ERR(key);
|
|
goto error;
|
|
}
|
|
|
|
/* make the changes with the locks held to prevent chown/chmod
|
|
* races */
|
|
ret = -EACCES;
|
|
down_write(&key->sem);
|
|
write_lock(&key->lock);
|
|
|
|
/* if we're not the sysadmin, we can only chmod a key that we
|
|
* own */
|
|
if (!capable(CAP_SYS_ADMIN) && key->uid != current->fsuid)
|
|
goto no_access;
|
|
|
|
/* changing the permissions mask */
|
|
key->perm = perm;
|
|
ret = 0;
|
|
|
|
no_access:
|
|
write_unlock(&key->lock);
|
|
up_write(&key->sem);
|
|
key_put(key);
|
|
error:
|
|
return ret;
|
|
|
|
} /* end keyctl_setperm_key() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* instantiate the key with the specified payload, and, if one is given, link
|
|
* the key into the keyring
|
|
*/
|
|
long keyctl_instantiate_key(key_serial_t id,
|
|
const void __user *_payload,
|
|
size_t plen,
|
|
key_serial_t ringid)
|
|
{
|
|
struct key *key, *keyring;
|
|
void *payload;
|
|
long ret;
|
|
|
|
ret = -EINVAL;
|
|
if (plen > 32767)
|
|
goto error;
|
|
|
|
/* pull the payload in if one was supplied */
|
|
payload = NULL;
|
|
|
|
if (_payload) {
|
|
ret = -ENOMEM;
|
|
payload = kmalloc(plen, GFP_KERNEL);
|
|
if (!payload)
|
|
goto error;
|
|
|
|
ret = -EFAULT;
|
|
if (copy_from_user(payload, _payload, plen) != 0)
|
|
goto error2;
|
|
}
|
|
|
|
/* find the target key (which must be writable) */
|
|
key = lookup_user_key(id, 0, 1, KEY_WRITE);
|
|
if (IS_ERR(key)) {
|
|
ret = PTR_ERR(key);
|
|
goto error2;
|
|
}
|
|
|
|
/* find the destination keyring if present (which must also be
|
|
* writable) */
|
|
keyring = NULL;
|
|
if (ringid) {
|
|
keyring = lookup_user_key(ringid, 1, 0, KEY_WRITE);
|
|
if (IS_ERR(keyring)) {
|
|
ret = PTR_ERR(keyring);
|
|
goto error3;
|
|
}
|
|
}
|
|
|
|
/* instantiate the key and link it into a keyring */
|
|
ret = key_instantiate_and_link(key, payload, plen, keyring);
|
|
|
|
key_put(keyring);
|
|
error3:
|
|
key_put(key);
|
|
error2:
|
|
kfree(payload);
|
|
error:
|
|
return ret;
|
|
|
|
} /* end keyctl_instantiate_key() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* negatively instantiate the key with the given timeout (in seconds), and, if
|
|
* one is given, link the key into the keyring
|
|
*/
|
|
long keyctl_negate_key(key_serial_t id, unsigned timeout, key_serial_t ringid)
|
|
{
|
|
struct key *key, *keyring;
|
|
long ret;
|
|
|
|
/* find the target key (which must be writable) */
|
|
key = lookup_user_key(id, 0, 1, KEY_WRITE);
|
|
if (IS_ERR(key)) {
|
|
ret = PTR_ERR(key);
|
|
goto error;
|
|
}
|
|
|
|
/* find the destination keyring if present (which must also be
|
|
* writable) */
|
|
keyring = NULL;
|
|
if (ringid) {
|
|
keyring = lookup_user_key(ringid, 1, 0, KEY_WRITE);
|
|
if (IS_ERR(keyring)) {
|
|
ret = PTR_ERR(keyring);
|
|
goto error2;
|
|
}
|
|
}
|
|
|
|
/* instantiate the key and link it into a keyring */
|
|
ret = key_negate_and_link(key, timeout, keyring);
|
|
|
|
key_put(keyring);
|
|
error2:
|
|
key_put(key);
|
|
error:
|
|
return ret;
|
|
|
|
} /* end keyctl_negate_key() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* the key control system call
|
|
*/
|
|
asmlinkage long sys_keyctl(int option, unsigned long arg2, unsigned long arg3,
|
|
unsigned long arg4, unsigned long arg5)
|
|
{
|
|
switch (option) {
|
|
case KEYCTL_GET_KEYRING_ID:
|
|
return keyctl_get_keyring_ID((key_serial_t) arg2,
|
|
(int) arg3);
|
|
|
|
case KEYCTL_JOIN_SESSION_KEYRING:
|
|
return keyctl_join_session_keyring((const char __user *) arg2);
|
|
|
|
case KEYCTL_UPDATE:
|
|
return keyctl_update_key((key_serial_t) arg2,
|
|
(const void __user *) arg3,
|
|
(size_t) arg4);
|
|
|
|
case KEYCTL_REVOKE:
|
|
return keyctl_revoke_key((key_serial_t) arg2);
|
|
|
|
case KEYCTL_DESCRIBE:
|
|
return keyctl_describe_key((key_serial_t) arg2,
|
|
(char __user *) arg3,
|
|
(unsigned) arg4);
|
|
|
|
case KEYCTL_CLEAR:
|
|
return keyctl_keyring_clear((key_serial_t) arg2);
|
|
|
|
case KEYCTL_LINK:
|
|
return keyctl_keyring_link((key_serial_t) arg2,
|
|
(key_serial_t) arg3);
|
|
|
|
case KEYCTL_UNLINK:
|
|
return keyctl_keyring_unlink((key_serial_t) arg2,
|
|
(key_serial_t) arg3);
|
|
|
|
case KEYCTL_SEARCH:
|
|
return keyctl_keyring_search((key_serial_t) arg2,
|
|
(const char __user *) arg3,
|
|
(const char __user *) arg4,
|
|
(key_serial_t) arg5);
|
|
|
|
case KEYCTL_READ:
|
|
return keyctl_read_key((key_serial_t) arg2,
|
|
(char __user *) arg3,
|
|
(size_t) arg4);
|
|
|
|
case KEYCTL_CHOWN:
|
|
return keyctl_chown_key((key_serial_t) arg2,
|
|
(uid_t) arg3,
|
|
(gid_t) arg4);
|
|
|
|
case KEYCTL_SETPERM:
|
|
return keyctl_setperm_key((key_serial_t) arg2,
|
|
(key_perm_t) arg3);
|
|
|
|
case KEYCTL_INSTANTIATE:
|
|
return keyctl_instantiate_key((key_serial_t) arg2,
|
|
(const void __user *) arg3,
|
|
(size_t) arg4,
|
|
(key_serial_t) arg5);
|
|
|
|
case KEYCTL_NEGATE:
|
|
return keyctl_negate_key((key_serial_t) arg2,
|
|
(unsigned) arg3,
|
|
(key_serial_t) arg4);
|
|
|
|
default:
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
} /* end sys_keyctl() */
|