path: root/security/tomoyo/file.c

/*
 * security/tomoyo/file.c
 *
 * Copyright (C) 2005-2011  NTT DATA CORPORATION
 */

#include "common.h"
#include <linux/slab.h>

/*
 * Mapping table from "enum tomoyo_path_acl_index" to "enum tomoyo_mac_index".
 */
static const u8 tomoyo_p2mac[TOMOYO_MAX_PATH_OPERATION] = {
	[TOMOYO_TYPE_EXECUTE]    = TOMOYO_MAC_FILE_EXECUTE,
	[TOMOYO_TYPE_READ]       = TOMOYO_MAC_FILE_OPEN,
	[TOMOYO_TYPE_WRITE]      = TOMOYO_MAC_FILE_OPEN,
	[TOMOYO_TYPE_APPEND]     = TOMOYO_MAC_FILE_OPEN,
	[TOMOYO_TYPE_UNLINK]     = TOMOYO_MAC_FILE_UNLINK,
	[TOMOYO_TYPE_GETATTR]    = TOMOYO_MAC_FILE_GETATTR,
	[TOMOYO_TYPE_RMDIR]      = TOMOYO_MAC_FILE_RMDIR,
	[TOMOYO_TYPE_TRUNCATE]   = TOMOYO_MAC_FILE_TRUNCATE,
	[TOMOYO_TYPE_SYMLINK]    = TOMOYO_MAC_FILE_SYMLINK,
	[TOMOYO_TYPE_CHROOT]     = TOMOYO_MAC_FILE_CHROOT,
	[TOMOYO_TYPE_UMOUNT]     = TOMOYO_MAC_FILE_UMOUNT,
};

/*
 * Mapping table from "enum tomoyo_mkdev_acl_index" to "enum tomoyo_mac_index".
 */
const u8 tomoyo_pnnn2mac[TOMOYO_MAX_MKDEV_OPERATION] = {
	[TOMOYO_TYPE_MKBLOCK] = TOMOYO_MAC_FILE_MKBLOCK,
	[TOMOYO_TYPE_MKCHAR]  = TOMOYO_MAC_FILE_MKCHAR,
};

/*
 * Mapping table from "enum tomoyo_path2_acl_index" to "enum tomoyo_mac_index".
 */
const u8 tomoyo_pp2mac[TOMOYO_MAX_PATH2_OPERATION] = {
	[TOMOYO_TYPE_LINK]       = TOMOYO_MAC_FILE_LINK,
	[TOMOYO_TYPE_RENAME]     = TOMOYO_MAC_FILE_RENAME,
	[TOMOYO_TYPE_PIVOT_ROOT] = TOMOYO_MAC_FILE_PIVOT_ROOT,
};

/*
 * Mapping table from "enum tomoyo_path_number_acl_index" to
 * "enum tomoyo_mac_index".
 */
const u8 tomoyo_pn2mac[TOMOYO_MAX_PATH_NUMBER_OPERATION] = {
	[TOMOYO_TYPE_CREATE] = TOMOYO_MAC_FILE_CREATE,
	[TOMOYO_TYPE_MKDIR]  = TOMOYO_MAC_FILE_MKDIR,
	[TOMOYO_TYPE_MKFIFO] = TOMOYO_MAC_FILE_MKFIFO,
	[TOMOYO_TYPE_MKSOCK] = TOMOYO_MAC_FILE_MKSOCK,
	[TOMOYO_TYPE_IOCTL]  = TOMOYO_MAC_FILE_IOCTL,
	[TOMOYO_TYPE_CHMOD]  = TOMOYO_MAC_FILE_CHMOD,
	[TOMOYO_TYPE_CHOWN]  = TOMOYO_MAC_FILE_CHOWN,
	[TOMOYO_TYPE_CHGRP]  = TOMOYO_MAC_FILE_CHGRP,
};

/**
 * tomoyo_put_name_union - Drop reference on "struct tomoyo_name_union".
 *
 * @ptr: Pointer to "struct tomoyo_name_union".
 *
 * Returns nothing.
 */
void tomoyo_put_name_union(struct tomoyo_name_union *ptr)
{
	tomoyo_put_group(ptr->group);
	tomoyo_put_name(ptr->filename);
}

/**
 * tomoyo_compare_name_union - Check whether a name matches "struct tomoyo_name_union" or not.
 *
 * @name: Pointer to "struct tomoyo_path_info".
 * @ptr:  Pointer to "struct tomoyo_name_union".
 *
 * Returns "struct tomoyo_path_info" if @name matches @ptr, NULL otherwise.
 */
const struct tomoyo_path_info *
tomoyo_compare_name_union(const struct tomoyo_path_info *name,
			  const struct tomoyo_name_union *ptr)
{
	if (ptr->group)
		return tomoyo_path_matches_group(name, ptr->group);
	if (tomoyo_path_matches_pattern(name, ptr->filename))
		return ptr->filename;
	return NULL;
}

/**
 * tomoyo_put_number_union - Drop reference on "struct tomoyo_number_union".
 *
 * @ptr: Pointer to "struct tomoyo_number_union".
 *
 * Returns nothing.
 */
void tomoyo_put_number_union(struct tomoyo_number_union *ptr)
{
	tomoyo_put_group(ptr->group);
}

/**
 * tomoyo_compare_number_union - Check whether a value matches "struct tomoyo_number_union" or not.
 *
 * @value: Number to check.
 * @ptr:   Pointer to "struct tomoyo_number_union".
 *
 * Returns true if @value matches @ptr, false otherwise.
 */
bool tomoyo_compare_number_union(const unsigned long value,
				 const struct tomoyo_number_union *ptr)
{
	if (ptr->group)
		return tomoyo_number_matches_group(value, value, ptr->group);
	return value >= ptr->values[0] && value <= ptr->values[1];
}

/**
 * tomoyo_add_slash - Add trailing '/' if needed.
 *
 * @buf: Pointer to "struct tomoyo_path_info".
 *
 * Returns nothing.
 *
 * @buf must be generated by tomoyo_encode() because this function does not
 * allocate memory for adding '/'.
 */
static void tomoyo_add_slash(struct tomoyo_path_info *buf)
{
	if (buf->is_dir)
		return;
	/*
	 * This is OK because tomoyo_encode() reserves space for appending "/".
	 */
	strcat((char *) buf->name, "/");
	tomoyo_fill_path_info(buf);
}

/**
 * tomoyo_get_realpath - Get realpath.
 *
 * @buf:  Pointer to "struct tomoyo_path_info".
 * @path: Pointer to "struct path".
 *
 * Returns true on success, false otherwise.
 */
static bool tomoyo_get_realpath(struct tomoyo_path_info *buf, struct path *path)
{
	buf->name = tomoyo_realpath_from_path(path);
	if (buf->name) {
		tomoyo_fill_path_info(buf);
		return true;
	}
	return false;
}

/**
 * tomoyo_audit_path_log - Audit path request log.
 *
 * @r: Pointer to "struct tomoyo_request_info".
 *
 * Returns 0 on success, negative value otherwise.
 */
static int tomoyo_audit_path_log(struct tomoyo_request_info *r)
{
	return tomoyo_supervisor(r, "file %s %s\n", tomoyo_path_keyword
				 [r->param.path.operation],
				 r->param.path.filename->name);
}

/**
 * tomoyo_audit_path2_log - Audit path/path request log.
 *
 * @r: Pointer to "struct tomoyo_request_info".
 *
 * Returns 0 on success, negative value otherwise.
 */
static int tomoyo_audit_path2_log(struct tomoyo_request_info *r)
{
	re