webusb.c

/*
 * Copyright (c) 2016, Devan Lai
 *
 * Permission to use, copy, modify, and/or distribute this software
 * for any purpose with or without fee is hereby granted, provided
 * that the above copyright notice and this permission notice
 * appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
 * AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <string.h>

#include "util.h"
#include "webusb.h"
#include "usb21_standard.h"

const struct webusb_platform_descriptor webusb_platform_capability_descriptor = {
	.bLength = WEBUSB_PLATFORM_DESCRIPTOR_SIZE,
	.bDescriptorType = USB_DT_DEVICE_CAPABILITY,
	.bDevCapabilityType = USB_DC_PLATFORM,
	.bReserved = 0,
	.platformCapabilityUUID = WEBUSB_UUID,
	.bcdVersion = 0x0100,
	.bVendorCode = WEBUSB_VENDOR_CODE,
	.iLandingPage = 1
};

const struct webusb_platform_descriptor webusb_platform_capability_descriptor_no_landing_page = {
	.bLength = WEBUSB_PLATFORM_DESCRIPTOR_SIZE,
	.bDescriptorType = USB_DT_DEVICE_CAPABILITY,
	.bDevCapabilityType = USB_DC_PLATFORM,
	.bReserved = 0,
	.platformCapabilityUUID = WEBUSB_UUID,
	.bcdVersion = 0x0100,
	.bVendorCode = WEBUSB_VENDOR_CODE,
	.iLandingPage = 0
};

static const char* webusb_https_url;

static int webusb_control_vendor_request(usbd_device *usbd_dev,
									 struct usb_setup_data *req,
									 uint8_t **buf, uint16_t *len,
									 usbd_control_complete_callback* complete) {
	(void)complete;
	(void)usbd_dev;

	wait_random();

	if (req->bRequest != WEBUSB_VENDOR_CODE) {
		return USBD_REQ_NEXT_CALLBACK;
	}

	int status = USBD_REQ_NOTSUPP;
	switch (req->wIndex) {
		case WEBUSB_REQ_GET_URL: {
			struct webusb_url_descriptor* url = (struct webusb_url_descriptor*)(*buf);
			uint16_t index = req->wValue;
			if (index == 0) {
				return USBD_REQ_NOTSUPP;
			}

			if (index == 1) {
				size_t url_len = strlen(webusb_https_url);
				url->bLength = WEBUSB_DT_URL_DESCRIPTOR_SIZE + url_len;
				url->bDescriptorType = WEBUSB_DT_URL;
				url->bScheme = WEBUSB_URL_SCHEME_HTTPS;
				memcpy(&url->URL, webusb_https_url, url_len);
				*len = MIN_8bits(*len, url->bLength);
				status = USBD_REQ_HANDLED;
			} else {
				// TODO: stall instead?
				status = USBD_REQ_NOTSUPP;
			}
			break;
		}
		default: {
			status = USBD_REQ_NOTSUPP;
			break;
		}
	}

	return status;
}

static void webusb_set_config(usbd_device* usbd_dev, uint16_t wValue) {
	(void)wValue;
	usbd_register_control_callback(
		usbd_dev,
		USB_REQ_TYPE_VENDOR | USB_REQ_TYPE_DEVICE,
		USB_REQ_TYPE_TYPE | USB_REQ_TYPE_RECIPIENT,
		webusb_control_vendor_request);
}

void webusb_setup(usbd_device* usbd_dev, const char* https_url) {
	webusb_https_url = https_url;

	usbd_register_set_config_callback(usbd_dev, webusb_set_config);
}