@@ -143,3 +143,16 @@ Description:
qw_sign an identifier to be reported as "OS String"
proper
============= ===============================================
+
+What: /config/usb-gadget/gadget/webusb
+Date: Dec 2022
+KernelVersion: 6.3
+Description:
+ This group contains "WebUSB" extension handling attributes.
+
+ ============= ===============================================
+ use flag turning "WebUSB" support on/off
+ bcdVersion bcd WebUSB specification version number
+ bVendorCode one-byte value used for custom per-device
+ landingPage UTF-8 encoded URL of the device's landing page
+ ============= ===============================================
@@ -14,9 +14,11 @@
#include <linux/device.h>
#include <linux/utsname.h>
#include <linux/bitfield.h>
+#include <linux/uuid.h>
#include <linux/usb/composite.h>
#include <linux/usb/otg.h>
+#include <linux/usb/webusb.h>
#include <asm/unaligned.h>
#include "u_os_desc.h"
@@ -713,14 +715,16 @@ static int bos_desc(struct usb_composite_dev *cdev)
* A SuperSpeed device shall include the USB2.0 extension descriptor
* and shall support LPM when operating in USB2.0 HS mode.
*/
- usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
- bos->bNumDeviceCaps++;
- le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
- usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
- usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
- usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
- usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT |
- USB_BESL_SUPPORT | besl);
+ if (cdev->gadget->lpm_capable) {
+ usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
+ bos->bNumDeviceCaps++;
+ le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
+ usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
+ usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
+ usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
+ usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT |
+ USB_BESL_SUPPORT | besl);
+ }
/*
* The Superspeed USB Capability descriptor shall be implemented by all
@@ -821,6 +825,37 @@ static int bos_desc(struct usb_composite_dev *cdev)
}
}
+ /* The WebUSB Platform Capability descriptor */
+ if (cdev->use_webusb) {
+ struct usb_plat_dev_cap_descriptor *webusb_cap;
+ struct usb_webusb_cap_data *webusb_cap_data;
+ uuid_t webusb_uuid = WEBUSB_UUID;
+
+ webusb_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
+ webusb_cap_data = (struct usb_webusb_cap_data *) webusb_cap->CapabilityData;
+ bos->bNumDeviceCaps++;
+ le16_add_cpu(&bos->wTotalLength,
+ USB_DT_USB_PLAT_DEV_CAP_SIZE(USB_WEBUSB_CAP_DATA_SIZE));
+
+ webusb_cap->bLength = USB_DT_USB_PLAT_DEV_CAP_SIZE(USB_WEBUSB_CAP_DATA_SIZE);
+ webusb_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
+ webusb_cap->bDevCapabilityType = USB_PLAT_DEV_CAP_TYPE;
+ webusb_cap->bReserved = 0;
+ export_uuid(webusb_cap->UUID, &webusb_uuid);
+
+ if (cdev->bcd_webusb_version != 0)
+ webusb_cap_data->bcdVersion = cpu_to_le16(cdev->bcd_webusb_version);
+ else
+ webusb_cap_data->bcdVersion = WEBUSB_VERSION_1_00;
+
+ webusb_cap_data->bVendorCode = cdev->b_webusb_vendor_code;
+
+ if (strnlen(cdev->landing_page, sizeof(cdev->landing_page)) > 0)
+ webusb_cap_data->iLandingPage = WEBUSB_LANDING_PAGE_PRESENT;
+ else
+ webusb_cap_data->iLandingPage = WEBUSB_LANDING_PAGE_NOT_PRESENT;
+ }
+
return le16_to_cpu(bos->wTotalLength);
}
@@ -1744,7 +1779,7 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
cdev->desc.bcdUSB = cpu_to_le16(0x0210);
}
} else {
- if (gadget->lpm_capable)
+ if (gadget->lpm_capable || cdev->use_webusb)
cdev->desc.bcdUSB = cpu_to_le16(0x0201);
else
cdev->desc.bcdUSB = cpu_to_le16(0x0200);
@@ -1779,7 +1814,7 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
break;
case USB_DT_BOS:
if (gadget_is_superspeed(gadget) ||
- gadget->lpm_capable) {
+ gadget->lpm_capable || cdev->use_webusb) {
value = bos_desc(cdev);
value = min(w_length, (u16) value);
}
@@ -2013,6 +2048,53 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
goto check_value;
}
+ /*
+ * WebUSB URL descriptor handling, following:
+ * https://wicg.github.io/webusb/#device-requests
+ */
+ if (cdev->use_webusb &&
+ ctrl->bRequestType == (USB_DIR_IN | USB_TYPE_VENDOR) &&
+ w_index == WEBUSB_GET_URL &&
+ w_value == WEBUSB_LANDING_PAGE_PRESENT &&
+ ctrl->bRequest == cdev->b_webusb_vendor_code) {
+ unsigned int landing_page_length;
+ unsigned int landing_page_offset;
+ struct webusb_url_descriptor *url_descriptor =
+ (struct webusb_url_descriptor *)cdev->req->buf;
+
+ url_descriptor->bDescriptorType = WEBUSB_URL_DESCRIPTOR_TYPE;
+
+ if (strncasecmp(cdev->landing_page, "https://", 8) == 0) {
+ landing_page_offset = 8;
+ url_descriptor->bScheme = WEBUSB_URL_SCHEME_HTTPS;
+ } else if (strncasecmp(cdev->landing_page, "http://", 7) == 0) {
+ landing_page_offset = 7;
+ url_descriptor->bScheme = WEBUSB_URL_SCHEME_HTTP;
+ } else {
+ landing_page_offset = 0;
+ url_descriptor->bScheme = WEBUSB_URL_SCHEME_NONE;
+ }
+
+ landing_page_length = strnlen(cdev->landing_page,
+ sizeof(url_descriptor->URL)
+ - WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH + landing_page_offset);
+
+ if (ctrl->wLength < WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH
+ + landing_page_length)
+ landing_page_length = ctrl->wLength
+ - WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH + landing_page_offset;
+
+ memcpy(url_descriptor->URL,
+ cdev->landing_page + landing_page_offset,
+ landing_page_length - landing_page_offset);
+ url_descriptor->bLength = landing_page_length
+ - landing_page_offset + WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH;
+
+ value = url_descriptor->bLength;
+
+ goto check_value;
+ }
+
VDBG(cdev,
"non-core control req%02x.%02x v%04x i%04x l%d\n",
ctrl->bRequestType, ctrl->bRequest,
@@ -7,6 +7,7 @@
#include <linux/nls.h>
#include <linux/usb/composite.h>
#include <linux/usb/gadget_configfs.h>
+#include <linux/usb/webusb.h>
#include "configfs.h"
#include "u_f.h"
#include "u_os_desc.h"
@@ -39,6 +40,7 @@ struct gadget_info {
struct config_group configs_group;
struct config_group strings_group;
struct config_group os_desc_group;
+ struct config_group webusb_group;
struct mutex lock;
struct usb_gadget_strings *gstrings[MAX_USB_STRING_LANGS + 1];
@@ -50,6 +52,11 @@ struct gadget_info {
bool use_os_desc;
char b_vendor_code;
char qw_sign[OS_STRING_QW_SIGN_LEN];
+ bool use_webusb;
+ u16 bcd_webusb_version;
+ u8 b_webusb_vendor_code;
+ char landing_page[WEBUSB_URL_RAW_MAX_LENGTH];
+
spinlock_t spinlock;
bool unbind;
};
@@ -780,6 +787,154 @@ static void gadget_strings_attr_release(struct config_item *item)
USB_CONFIG_STRING_RW_OPS(gadget_strings);
USB_CONFIG_STRINGS_LANG(gadget_strings, gadget_info);
+static inline struct gadget_info *webusb_item_to_gadget_info(
+ struct config_item *item)
+{
+ return container_of(to_config_group(item),
+ struct gadget_info, webusb_group);
+}
+
+static ssize_t webusb_use_show(struct config_item *item, char *page)
+{
+ return sysfs_emit(page, "%d\n",
+ webusb_item_to_gadget_info(item)->use_webusb);
+}
+
+static ssize_t webusb_use_store(struct config_item *item, const char *page,
+ size_t len)
+{
+ struct gadget_info *gi = webusb_item_to_gadget_info(item);
+ int ret;
+ bool use;
+
+ mutex_lock(&gi->lock);
+ ret = kstrtobool(page, &use);
+ if (!ret) {
+ gi->use_webusb = use;
+ ret = len;
+ }
+ mutex_unlock(&gi->lock);
+
+ return ret;
+}
+
+static ssize_t webusb_bcdVersion_show(struct config_item *item, char *page)
+{
+ return sysfs_emit(page, "0x%04x\n",
+ webusb_item_to_gadget_info(item)->bcd_webusb_version);
+}
+
+static ssize_t webusb_bcdVersion_store(struct config_item *item,
+ const char *page, size_t len)
+{
+ struct gadget_info *gi = webusb_item_to_gadget_info(item);
+ u16 bcdVersion;
+ int ret;
+
+ mutex_lock(&gi->lock);
+ ret = kstrtou16(page, 0, &bcdVersion);
+ if (ret)
+ goto out;
+ ret = is_valid_bcd(bcdVersion);
+ if (ret)
+ goto out;
+
+ gi->bcd_webusb_version = bcdVersion;
+ ret = len;
+
+out:
+ mutex_unlock(&gi->lock);
+
+ return ret;
+}
+
+static ssize_t webusb_bVendorCode_show(struct config_item *item, char *page)
+{
+ return sysfs_emit(page, "0x%02x\n",
+ webusb_item_to_gadget_info(item)->b_webusb_vendor_code);
+}
+
+static ssize_t webusb_bVendorCode_store(struct config_item *item,
+ const char *page, size_t len)
+{
+ struct gadget_info *gi = webusb_item_to_gadget_info(item);
+ int ret;
+ u8 b_vendor_code;
+
+ mutex_lock(&gi->lock);
+ ret = kstrtou8(page, 0, &b_vendor_code);
+ if (!ret) {
+ gi->b_webusb_vendor_code = b_vendor_code;
+ ret = len;
+ }
+ mutex_unlock(&gi->lock);
+
+ return ret;
+}
+
+static ssize_t webusb_landingPage_show(struct config_item *item, char *page)
+{
+ return sysfs_emit(page, "%s\n", webusb_item_to_gadget_info(item)->landing_page);
+}
+
+static ssize_t webusb_landingPage_store(struct config_item *item, const char *page,
+ size_t len)
+{
+ struct gadget_info *gi = webusb_item_to_gadget_info(item);
+ unsigned int bytes_to_strip = 0;
+ int l = len;
+
+ if (page[l - 1] == '\n') {
+ --l;
+ ++bytes_to_strip;
+ }
+
+ if (l > sizeof(gi->landing_page)) {
+ pr_err("webusb: landingPage URL too long\n");
+ return -EINVAL;
+ }
+
+ // validation
+ if (strncasecmp(page, "https://", 8) == 0)
+ bytes_to_strip = 8;
+ else if (strncasecmp(page, "http://", 7) == 0)
+ bytes_to_strip = 7;
+ else
+ bytes_to_strip = 0;
+
+ if (l > U8_MAX - WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH + bytes_to_strip) {
+ pr_err("webusb: landingPage URL %d bytes too long for given URL scheme\n",
+ l - U8_MAX + WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH - bytes_to_strip);
+ return -EINVAL;
+ }
+
+ mutex_lock(&gi->lock);
+ // ensure 0 bytes are set, in case the new landing page is shorter then the old one.
+ memset(gi->landing_page, 0, sizeof(gi->landing_page));
+ memcpy(gi->landing_page, page, l);
+ mutex_unlock(&gi->lock);
+
+ return len;
+}
+
+CONFIGFS_ATTR(webusb_, use);
+CONFIGFS_ATTR(webusb_, bVendorCode);
+CONFIGFS_ATTR(webusb_, bcdVersion);
+CONFIGFS_ATTR(webusb_, landingPage);
+
+static struct configfs_attribute *webusb_attrs[] = {
+ &webusb_attr_use,
+ &webusb_attr_bcdVersion,
+ &webusb_attr_bVendorCode,
+ &webusb_attr_landingPage,
+ NULL,
+};
+
+static struct config_item_type webusb_type = {
+ .ct_attrs = webusb_attrs,
+ .ct_owner = THIS_MODULE,
+};
+
static inline struct gadget_info *os_desc_item_to_gadget_info(
struct config_item *item)
{
@@ -1341,6 +1496,13 @@ static int configfs_composite_bind(struct usb_gadget *gadget,
gi->cdev.desc.iSerialNumber = s[USB_GADGET_SERIAL_IDX].id;
}
+ if (gi->use_webusb) {
+ cdev->use_webusb = true;
+ cdev->bcd_webusb_version = gi->bcd_webusb_version;
+ cdev->b_webusb_vendor_code = gi->b_webusb_vendor_code;
+ memcpy(cdev->landing_page, gi->landing_page, WEBUSB_URL_RAW_MAX_LENGTH);
+ }
+
if (gi->use_os_desc) {
cdev->use_os_string = true;
cdev->b_vendor_code = gi->b_vendor_code;
@@ -1605,6 +1767,10 @@ static struct config_group *gadgets_make(
&os_desc_type);
configfs_add_default_group(&gi->os_desc_group, &gi->group);
+ config_group_init_type_name(&gi->webusb_group, "webusb",
+ &webusb_type);
+ configfs_add_default_group(&gi->webusb_group, &gi->group);
+
gi->composite.bind = configfs_do_nothing;
gi->composite.unbind = configfs_do_nothing;
gi->composite.suspend = NULL;
@@ -25,6 +25,7 @@
#include <linux/version.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
+#include <linux/usb/webusb.h>
#include <linux/log2.h>
#include <linux/configfs.h>
@@ -474,6 +475,12 @@ struct usb_composite_dev {
struct usb_configuration *os_desc_config;
unsigned int use_os_string:1;
+ /* WebUSB */
+ u16 bcd_webusb_version;
+ u8 b_webusb_vendor_code;
+ char landing_page[WEBUSB_URL_RAW_MAX_LENGTH];
+ unsigned int use_webusb:1;
+
/* private: */
/* internals */
unsigned int suspended:1;
new file mode 100644
@@ -0,0 +1,83 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * WebUSB descriptors and constants
+ *
+ * Copyright (C) 2023 Jó Ágila Bitsch <jgilab@gmail.com>
+ */
+
+#ifndef __LINUX_USB_WEBUSB_H
+#define __LINUX_USB_WEBUSB_H
+
+#include "uapi/linux/usb/ch9.h"
+
+/*
+ * little endian PlatformCapablityUUID for WebUSB
+ * 3408b638-09a9-47a0-8bfd-a0768815b665
+ * to identify Platform Device Capability descriptors as referring to WebUSB
+ *
+ * the UUID above MUST be sent over the wire as the byte sequence:
+ * {0x38, 0xB6, 0x08, 0x34, 0xA9, 0x09, 0xA0, 0x47, 0x8B, 0xFD, 0xA0, 0x76, 0x88, 0x15, 0xB6, 0x65}.
+ */
+#define WEBUSB_UUID \
+ UUID_INIT(0x38b60834, 0xa909, 0xa047, 0x8b, 0xfd, 0xa0, 0x76, 0x88, 0x15, 0xb6, 0x65)
+
+/*
+ * WebUSB Platform Capability data
+ *
+ * A device announces support for the
+ * WebUSB command set by including the following Platform Descriptor Data in its
+ * Binary Object Store associated with the WebUSB_UUID above.
+ * See: https://wicg.github.io/webusb/#webusb-platform-capability-descriptor
+ */
+struct usb_webusb_cap_data {
+ __le16 bcdVersion;
+#define WEBUSB_VERSION_1_00 cpu_to_le16(0x0100) /* currently only version 1.00 is defined */
+ u8 bVendorCode;
+ u8 iLandingPage;
+#define WEBUSB_LANDING_PAGE_NOT_PRESENT 0
+#define WEBUSB_LANDING_PAGE_PRESENT 1 /* we chose the fixed index 1 for the URL descriptor */
+} __packed;
+
+#define USB_WEBUSB_CAP_DATA_SIZE 4
+
+/*
+ * Get URL Request
+ *
+ * The request to fetch an URL is defined in https://wicg.github.io/webusb/#get-url as:
+ * bmRequestType: (USB_DIR_IN | USB_TYPE_VENDOR) = 11000000B
+ * bRequest: bVendorCode
+ * wValue: iLandingPage
+ * wIndex: GET_URL = 2
+ * wLength: Descriptor Length (typically U8_MAX = 255)
+ * Data: URL Descriptor
+ */
+#define WEBUSB_GET_URL 2
+
+/*
+ * This descriptor contains a single URL and is returned by the Get URL request.
+ *
+ * See: https://wicg.github.io/webusb/#url-descriptor
+ */
+struct webusb_url_descriptor {
+ u8 bLength;
+#define WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH 3
+ u8 bDescriptorType;
+#define WEBUSB_URL_DESCRIPTOR_TYPE 3
+ u8 bScheme;
+#define WEBUSB_URL_SCHEME_HTTP 0
+#define WEBUSB_URL_SCHEME_HTTPS 1
+#define WEBUSB_URL_SCHEME_NONE 255
+ u8 URL[U8_MAX - WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH];
+} __packed;
+
+/*
+ * Buffer size to hold the longest URL that can be in an URL descriptor
+ *
+ * The descriptor can be U8_MAX bytes long.
+ * WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH bytes are used for a header.
+ * Since the longest prefix that might be stripped is "https://", we may accommodate an additional
+ * 8 bytes.
+ */
+#define WEBUSB_URL_RAW_MAX_LENGTH (U8_MAX - WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH + 8)
+
+#endif /* __LINUX_USB_USBNET_H */
@@ -947,6 +947,22 @@ struct usb_ss_container_id_descriptor {
#define USB_DT_USB_SS_CONTN_ID_SIZE 20
+/*
+ * Platform Device Capability descriptor: Defines platform specific device
+ * capabilities
+ */
+#define USB_PLAT_DEV_CAP_TYPE 5
+struct usb_plat_dev_cap_descriptor {
+ __u8 bLength;
+ __u8 bDescriptorType;
+ __u8 bDevCapabilityType;
+ __u8 bReserved;
+ __u8 UUID[16];
+ __u8 CapabilityData[];
+} __attribute__((packed));
+
+#define USB_DT_USB_PLAT_DEV_CAP_SIZE(capability_data_size) (20 + capability_data_size)
+
/*
* SuperSpeed Plus USB Capability descriptor: Defines the set of
* SuperSpeed Plus USB specific device level capabilities