path: root/drivers/thunderbolt/domain.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Thunderbolt bus support
 *
 * Copyright (C) 2017, Intel Corporation
 * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
 */

#include <linux/device.h>
#include <linux/idr.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/random.h>
#include <crypto/hash.h>

#include "tb.h"

static DEFINE_IDA(tb_domain_ida);

static bool match_service_id(const struct tb_service_id *id,
			     const struct tb_service *svc)
{
	if (id->match_flags & TBSVC_MATCH_PROTOCOL_KEY) {
		if (strcmp(id->protocol_key, svc->key))
			return false;
	}

	if (id->match_flags & TBSVC_MATCH_PROTOCOL_ID) {
		if (id->protocol_id != svc->prtcid)
			return false;
	}

	if (id->match_flags & TBSVC_MATCH_PROTOCOL_VERSION) {
		if (id->protocol_version != svc->prtcvers)
			return false;
	}

	if (id->match_flags & TBSVC_MATCH_PROTOCOL_VERSION) {
		if (id->protocol_revision != svc->prtcrevs)
			return false;
	}

	return true;
}

static const struct tb_service_id *__tb_service_match(struct device *dev,
						      struct device_driver *drv)
{
	struct tb_service_driver *driver;
	const struct tb_service_id *ids;
	struct tb_service *svc;

	svc = tb_to_service(dev);
	if (!svc)
		return NULL;

	driver = container_of(drv, struct tb_service_driver, driver);
	if (!driver->id_table)
		return NULL;

	for (ids = driver->id_table; ids->match_flags != 0; ids++) {
		if (match_service_id(ids, svc))
			return ids;
	}

	return NULL;
}

static int tb_service_match(struct device *dev, struct device_driver *drv)
{
	return !!__tb_service_match(dev, drv);
}

static int tb_service_probe(struct device *dev)
{
	struct tb_service *svc = tb_to_service(dev);
	struct tb_service_driver *driver;
	const struct tb_service_id *id;

	driver = container_of(dev->driver, struct tb_service_driver, driver);
	id = __tb_service_match(dev, &driver->driver);

	return driver->probe(svc, id);
}

static void tb_service_remove(struct device *dev)
{
	struct tb_service *svc = tb_to_service(dev);
	struct tb_service_driver *driver;

	driver = container_of(dev->driver, struct tb_service_driver, driver);
	if (driver->remove)
		driver->remove(svc);
}

static void tb_service_shutdown(struct device *dev)
{
	struct tb_service_driver *driver;
	struct tb_service *svc;

	svc = tb_to_service(dev);
	if (!svc || !dev->driver)
		return;

	driver = container_of(dev->driver, struct tb_service_driver, driver);
	if (driver->shutdown)
		driver->shutdown(svc);
}

static const char * const tb_security_names[] = {
	[TB_SECURITY_NONE] = "none",
	[TB_SECURITY_USER] = "user",
	[TB_SECURITY_SECURE] = "secure",
	[TB_SECURITY_DPONLY] = "dponly",
	[TB_SECURITY_USBONLY] = "usbonly",
	[TB_SECURITY_NOPCIE] = "nopcie",
};

static ssize_t boot_acl_show(struct device *dev, struct device_attribute *attr,
			     char *buf)
{
	struct tb *tb = container_of(dev, struct tb, dev);
	uuid_t *uuids;
	ssize_t ret;
	int i;

	uuids = kcalloc(tb->nboot_acl, sizeof(uuid_t), GFP_KERNEL);
	if (!uuids)
		return -ENOMEM;

	pm_runtime_get_sync(&tb->dev);

	if (mutex_lock_interruptible(&tb->lock)) {
		ret = -ERESTARTSYS;
		goto out;
	}
	ret = tb->cm_ops->get_boot_acl(tb, uuids, tb->nboot_acl);
	if (ret) {
		mutex_unlock(&tb->lock);
		goto out;
	}
	mutex_unlock(&tb->lock);

	for (ret = 0, i = 0; i < tb->nboot_acl; i++) {
		if (!uuid_is_null(&uuids[i]))
			ret += sysfs_emit_at(buf, ret, "%pUb", &uuids[i]);

		ret += sysfs_emit_at(buf, ret, "%s", i < tb->nboot_acl - 1 ? "," : "\n");
	}

out:
	pm_runtime_mark_last_busy(&tb->dev);
	pm_runtime_put_autosuspend(&tb->dev);
	kfree(uuids);

	return ret;
}

static ssize_t boot_acl_store(struct device *dev, struct device_attribute *attr,
			      const char *buf, size_t count)
{
	struct tb *tb = container_of(dev, struct tb, dev);
	char *str, *s, *uuid_str;
	ssize_t ret = 0;
	uuid_t *acl;
	int i = 0;

	/*
	 * Make sure the value is not bigger than tb->nboot_acl * UUID
	 * length + commas and optional "\n". Also the smallest allowable
	 * string is tb->nboot_acl * ",".
	 */
	if (count > (UUID_STRING_LEN + 1) * tb->nboot_acl + 1)
		return -EINVAL;
	if (count < tb->nboot_acl - 1)
		return -EINVAL;

	str = kstrdup(buf, GFP_KERNEL);
	if (!str)
		return -ENOMEM;

	acl = kcalloc(tb->nboot_acl, sizeof(uuid_t), GFP_KERNEL);
	if (!acl) {
		ret = -ENOMEM;
		goto err_free_str;
	}

	uuid_str = strim(str);
	while ((s = strsep(&uuid_str, ",")) != NULL && i < tb->nboot_acl) {
		size_t len = strlen(s);

		if (len) {
			if (len !=