// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2008 IBM Corporation
 *
 * Authors:
 * Mimi Zohar <zohar@us.ibm.com>
 *
 * File: integrity_iint.c
 *      - initialize the integrity directory in securityfs
 *      - load IMA and EVM keys
 */
#include <linux/security.h>
#include "integrity.h"

struct dentry *integrity_dir;

/*
 * integrity_kernel_read - read data from the file
 *
 * This is a function for reading file content instead of kernel_read().
 * It does not perform locking checks to ensure it cannot be blocked.
 * It does not perform security checks because it is irrelevant for IMA.
 *
 */
int integrity_kernel_read(struct file *file, loff_t offset,
                          void *addr, unsigned long count)
{
        return __kernel_read(file, addr, count, &offset);
}

/*
 * integrity_load_keys - load integrity keys hook
 *
 * Hooks is called from init/main.c:kernel_init_freeable()
 * when rootfs is ready
 */
void __init integrity_load_keys(void)
{
        ima_load_x509();

        if (!IS_ENABLED(CONFIG_IMA_LOAD_X509))
                evm_load_x509();
}

int __init integrity_fs_init(void)
{
        if (integrity_dir)
                return 0;

        integrity_dir = securityfs_create_dir("integrity", NULL);
        if (IS_ERR(integrity_dir)) {
                int ret = PTR_ERR(integrity_dir);

                if (ret != -ENODEV)
                        pr_err("Unable to create integrity sysfs dir: %d\n",
                               ret);
                integrity_dir = NULL;
                return ret;
        }

        return 0;
}

void __init integrity_fs_fini(void)
{
        if (!integrity_dir || !simple_empty(integrity_dir))
                return;

        securityfs_remove(integrity_dir);
        integrity_dir = NULL;
}