mirror of https://gitee.com/openkylin/linux.git
138 lines
3.4 KiB
C
138 lines
3.4 KiB
C
/*
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* AppArmor security module
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*
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* This file contains basic common functions used in AppArmor
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*
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* Copyright (C) 1998-2008 Novell/SUSE
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* Copyright 2009-2010 Canonical Ltd.
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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 as
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* published by the Free Software Foundation, version 2 of the
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* License.
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*/
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#include <linux/mm.h>
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#include <linux/slab.h>
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#include <linux/string.h>
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#include <linux/vmalloc.h>
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#include "include/audit.h"
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#include "include/apparmor.h"
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/**
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* aa_split_fqname - split a fqname into a profile and namespace name
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* @fqname: a full qualified name in namespace profile format (NOT NULL)
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* @ns_name: pointer to portion of the string containing the ns name (NOT NULL)
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*
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* Returns: profile name or NULL if one is not specified
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*
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* Split a namespace name from a profile name (see policy.c for naming
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* description). If a portion of the name is missing it returns NULL for
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* that portion.
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*
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* NOTE: may modify the @fqname string. The pointers returned point
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* into the @fqname string.
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*/
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char *aa_split_fqname(char *fqname, char **ns_name)
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{
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char *name = strim(fqname);
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*ns_name = NULL;
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if (name[0] == ':') {
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char *split = strchr(&name[1], ':');
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*ns_name = skip_spaces(&name[1]);
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if (split) {
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/* overwrite ':' with \0 */
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*split = 0;
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name = skip_spaces(split + 1);
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} else
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/* a ns name without a following profile is allowed */
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name = NULL;
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}
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if (name && *name == 0)
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name = NULL;
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return name;
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}
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/**
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* aa_info_message - log a none profile related status message
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* @str: message to log
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*/
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void aa_info_message(const char *str)
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{
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if (audit_enabled) {
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struct common_audit_data sa;
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struct apparmor_audit_data aad = {0,};
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COMMON_AUDIT_DATA_INIT(&sa, NONE);
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sa.aad = &aad;
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aad.info = str;
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aa_audit_msg(AUDIT_APPARMOR_STATUS, &sa, NULL);
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}
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printk(KERN_INFO "AppArmor: %s\n", str);
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}
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/**
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* kvmalloc - do allocation preferring kmalloc but falling back to vmalloc
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* @size: size of allocation
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*
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* Return: allocated buffer or NULL if failed
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*
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* It is possible that policy being loaded from the user is larger than
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* what can be allocated by kmalloc, in those cases fall back to vmalloc.
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*/
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void *kvmalloc(size_t size)
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{
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void *buffer = NULL;
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if (size == 0)
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return NULL;
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/* do not attempt kmalloc if we need more than 16 pages at once */
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if (size <= (16*PAGE_SIZE))
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buffer = kmalloc(size, GFP_NOIO | __GFP_NOWARN);
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if (!buffer) {
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/* see kvfree for why size must be at least work_struct size
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* when allocated via vmalloc
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*/
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if (size < sizeof(struct work_struct))
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size = sizeof(struct work_struct);
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buffer = vmalloc(size);
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}
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return buffer;
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}
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/**
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* do_vfree - workqueue routine for freeing vmalloced memory
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* @work: data to be freed
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*
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* The work_struct is overlaid to the data being freed, as at the point
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* the work is scheduled the data is no longer valid, be its freeing
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* needs to be delayed until safe.
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*/
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static void do_vfree(struct work_struct *work)
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{
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vfree(work);
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}
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/**
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* kvfree - free an allocation do by kvmalloc
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* @buffer: buffer to free (MAYBE_NULL)
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*
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* Free a buffer allocated by kvmalloc
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*/
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void kvfree(void *buffer)
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{
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if (is_vmalloc_addr(buffer)) {
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/* Data is no longer valid so just use the allocated space
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* as the work_struct
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*/
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struct work_struct *work = (struct work_struct *) buffer;
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INIT_WORK(work, do_vfree);
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schedule_work(work);
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} else
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kfree(buffer);
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}
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