diff options
Diffstat (limited to 'test/fuzz/device/net/src')
| -rw-r--r-- | test/fuzz/device/net/src/arch/cc.h | 75 | ||||
| -rw-r--r-- | test/fuzz/device/net/src/fuzz.cc | 99 | ||||
| -rw-r--r-- | test/fuzz/device/net/src/lwipopts.h | 71 | ||||
| -rw-r--r-- | test/fuzz/device/net/src/tusb_config.h | 122 | ||||
| -rw-r--r-- | test/fuzz/device/net/src/usb_descriptors.cc | 229 |
5 files changed, 596 insertions, 0 deletions
diff --git a/test/fuzz/device/net/src/arch/cc.h b/test/fuzz/device/net/src/arch/cc.h new file mode 100644 index 000000000..9f30b91cb --- /dev/null +++ b/test/fuzz/device/net/src/arch/cc.h @@ -0,0 +1,75 @@ +/* + * Copyright (c) 2001-2003 Swedish Institute of Computer Science. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without modification, + * are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT + * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT + * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING + * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY + * OF SUCH DAMAGE. + * + * This file is part of the lwIP TCP/IP stack. + * + * Author: Adam Dunkels <[email protected]> + * + */ +#ifndef __CC_H__ +#define __CC_H__ + +//#include "cpu.h" + +typedef int sys_prot_t; + + + +/* define compiler specific symbols */ +#if defined (__ICCARM__) + +#define PACK_STRUCT_BEGIN +#define PACK_STRUCT_STRUCT +#define PACK_STRUCT_END +#define PACK_STRUCT_FIELD(x) x +#define PACK_STRUCT_USE_INCLUDES + +#elif defined (__CC_ARM) + +#define PACK_STRUCT_BEGIN __packed +#define PACK_STRUCT_STRUCT +#define PACK_STRUCT_END +#define PACK_STRUCT_FIELD(x) x + +#elif defined (__GNUC__) + +#define PACK_STRUCT_BEGIN +#define PACK_STRUCT_STRUCT __attribute__ ((__packed__)) +#define PACK_STRUCT_END +#define PACK_STRUCT_FIELD(x) x + +#elif defined (__TASKING__) + +#define PACK_STRUCT_BEGIN +#define PACK_STRUCT_STRUCT +#define PACK_STRUCT_END +#define PACK_STRUCT_FIELD(x) x + +#endif + +#define LWIP_PLATFORM_ASSERT(x) do { if(!(x)) while(1); } while(0) + +#endif /* __CC_H__ */ diff --git a/test/fuzz/device/net/src/fuzz.cc b/test/fuzz/device/net/src/fuzz.cc new file mode 100644 index 000000000..a6935928a --- /dev/null +++ b/test/fuzz/device/net/src/fuzz.cc @@ -0,0 +1,99 @@ +/* + * The MIT License (MIT) + * + * Copyright (c) 2022 Nathaniel Brough + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + * + */ + +#include <cassert> +#include <fuzzer/FuzzedDataProvider.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "class/cdc/cdc_device.h" +#include "class/net/net_device.h" +#include "fuzz/fuzz.h" +#include "tusb.h" +#include <cstdint> +#include <string> +#include <vector> + +extern "C" { + +#define FUZZ_ITERATIONS 500 + +//--------------------------------------------------------------------+ +// MACRO CONSTANT TYPEDEF PROTYPES +//--------------------------------------------------------------------+ + +void net_task(FuzzedDataProvider *provider); + +extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) { + FuzzedDataProvider provider(Data, Size); + std::vector<uint8_t> callback_data = provider.ConsumeBytes<uint8_t>( + provider.ConsumeIntegralInRange<size_t>(0, Size)); + fuzz_init(callback_data.data(), callback_data.size()); + // init device stack on configured roothub port + tud_init(BOARD_TUD_RHPORT); + + for (int i = 0; i < FUZZ_ITERATIONS; i++) { + if (provider.remaining_bytes() == 0) { + return 0; + } + tud_int_handler(provider.ConsumeIntegral<uint8_t>()); + tud_task(); // tinyusb device task + net_task(&provider); + } + + return 0; +} + +//--------------------------------------------------------------------+ +// USB CDC +//--------------------------------------------------------------------+ +enum NetApiFuncs { + kNetworkRecvRenew, + kNetworkCanXmit, + kNetworkXmit, + kMaxValue, +}; + +void net_task(FuzzedDataProvider *provider) { + + assert(provider != NULL); + switch (provider->ConsumeEnum<NetApiFuncs>()) { + + case kNetworkRecvRenew: + tud_network_recv_renew(); + break; + case kNetworkCanXmit: + (void)tud_network_can_xmit(provider->ConsumeIntegral<uint16_t>()); + case kNetworkXmit: + // TODO: Actually pass real values here later. + tud_network_xmit(NULL, 0); + + case kMaxValue: + // Noop. + break; + } +} +} diff --git a/test/fuzz/device/net/src/lwipopts.h b/test/fuzz/device/net/src/lwipopts.h new file mode 100644 index 000000000..336c9243d --- /dev/null +++ b/test/fuzz/device/net/src/lwipopts.h @@ -0,0 +1,71 @@ +/* + * Copyright (c) 2001-2003 Swedish Institute of Computer Science. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without modification, + * are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT + * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT + * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING + * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY + * OF SUCH DAMAGE. + * + * This file is part of the lwIP TCP/IP stack. + * + * Author: Simon Goldschmidt + * + */ +#ifndef __LWIPOPTS_H__ +#define __LWIPOPTS_H__ + +/* Prevent having to link sys_arch.c (we don't test the API layers in unit tests) */ +#define NO_SYS 1 +#define MEM_ALIGNMENT 4 +#define LWIP_RAW 0 +#define LWIP_NETCONN 0 +#define LWIP_SOCKET 0 +#define LWIP_DHCP 0 +#define LWIP_ICMP 1 +#define LWIP_UDP 1 +#define LWIP_TCP 1 +#define LWIP_IPV4 1 +#define LWIP_IPV6 0 +#define ETH_PAD_SIZE 0 +#define LWIP_IP_ACCEPT_UDP_PORT(p) ((p) == PP_NTOHS(67)) + +#define TCP_MSS (1500 /*mtu*/ - 20 /*iphdr*/ - 20 /*tcphhr*/) +#define TCP_SND_BUF (2 * TCP_MSS) +#define TCP_WND (TCP_MSS) + +#define ETHARP_SUPPORT_STATIC_ENTRIES 1 + +#define LWIP_HTTPD_CGI 0 +#define LWIP_HTTPD_SSI 0 +#define LWIP_HTTPD_SSI_INCLUDE_TAG 0 + +#define LWIP_SINGLE_NETIF 1 + +#define PBUF_POOL_SIZE 2 + +#define HTTPD_USE_CUSTOM_FSDATA 0 + +#define LWIP_MULTICAST_PING 1 +#define LWIP_BROADCAST_PING 1 +#define LWIP_IPV6_MLD 0 +#define LWIP_IPV6_SEND_ROUTER_SOLICIT 0 + +#endif /* __LWIPOPTS_H__ */ diff --git a/test/fuzz/device/net/src/tusb_config.h b/test/fuzz/device/net/src/tusb_config.h new file mode 100644 index 000000000..6ad859337 --- /dev/null +++ b/test/fuzz/device/net/src/tusb_config.h @@ -0,0 +1,122 @@ +/* + * The MIT License (MIT) + * + * Copyright (c) 2022 Nathaniel Brough + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + * + */ + +#ifndef _TUSB_CONFIG_H_ +#define _TUSB_CONFIG_H_ + +#ifdef __cplusplus + extern "C" { +#endif + +//--------------------------------------------------------------------+ +// Board Specific Configuration +//--------------------------------------------------------------------+ + +// RHPort number used for device can be defined by board.mk, default to port 0 +#ifndef BOARD_TUD_RHPORT +#define BOARD_TUD_RHPORT 0 +#endif + +// RHPort max operational speed can defined by board.mk +#ifndef BOARD_TUD_MAX_SPEED +#define BOARD_TUD_MAX_SPEED OPT_MODE_DEFAULT_SPEED +#endif + +//-------------------------------------------------------------------- +// Common Configuration +//-------------------------------------------------------------------- + +// defined by compiler flags for flexibility +#ifndef CFG_TUSB_MCU +#error CFG_TUSB_MCU must be defined +#endif + +#ifndef CFG_TUSB_OS +#define CFG_TUSB_OS OPT_OS_NONE +#endif + +#ifndef CFG_TUSB_DEBUG +#define CFG_TUSB_DEBUG 0 +#endif + +// Enable Device stack +#define CFG_TUD_ENABLED 1 + +// Default is max speed that hardware controller could support with on-chip PHY +#define CFG_TUD_MAX_SPEED BOARD_TUD_MAX_SPEED + +/* USB DMA on some MCUs can only access a specific SRAM region with restriction on alignment. + * Tinyusb use follows macros to declare transferring memory so that they can be put + * into those specific section. + * e.g + * - CFG_TUSB_MEM SECTION : __attribute__ (( section(".usb_ram") )) + * - CFG_TUSB_MEM_ALIGN : __attribute__ ((aligned(4))) + */ +#ifndef CFG_TUSB_MEM_SECTION +#define CFG_TUSB_MEM_SECTION +#endif + +#ifndef CFG_TUSB_MEM_ALIGN +#define CFG_TUSB_MEM_ALIGN __attribute__ ((aligned(4))) +#endif + +//-------------------------------------------------------------------- +// DEVICE CONFIGURATION +//-------------------------------------------------------------------- + +#ifndef CFG_TUD_ENDPOINT0_SIZE +#define CFG_TUD_ENDPOINT0_SIZE 64 +#endif + +//------------- CLASS -------------// +#define CFG_TUD_CDC 1 +#define CFG_TUD_MSC 0 +#define CFG_TUD_HID 0 +#define CFG_TUD_MIDI 0 +#define CFG_TUD_VENDOR 0 + +// Network class has 2 drivers: ECM/RNDIS and NCM. +// Only one of the drivers can be enabled +#define CFG_TUD_ECM_RNDIS 1 +#define CFG_TUD_NCM (1-CFG_TUD_ECM_RNDIS) + +// CDC FIFO size of TX and RX +#define CFG_TUD_CDC_RX_BUFSIZE (TUD_OPT_HIGH_SPEED ? 512 : 64) +#define CFG_TUD_CDC_TX_BUFSIZE (TUD_OPT_HIGH_SPEED ? 512 : 64) + +// CDC Endpoint transfer buffer size, more is faster +#define CFG_TUD_CDC_EP_BUFSIZE (TUD_OPT_HIGH_SPEED ? 512 : 64) + +// MSC Buffer size of Device Mass storage +#define CFG_TUD_MSC_EP_BUFSIZE 512 + + + + +#ifdef __cplusplus + } +#endif + +#endif /* _TUSB_CONFIG_H_ */ diff --git a/test/fuzz/device/net/src/usb_descriptors.cc b/test/fuzz/device/net/src/usb_descriptors.cc new file mode 100644 index 000000000..5597d49d5 --- /dev/null +++ b/test/fuzz/device/net/src/usb_descriptors.cc @@ -0,0 +1,229 @@ +/* + * The MIT License (MIT) + * + * Copyright (c) 2022 Ha Thach (tinyusb.org) + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + * + */ + +#include "tusb.h" + +/* A combination of interfaces must have a unique product id, since PC will save + * device driver after the first plug. + * Auto ProductID layout's Bitmap: + * [MSB] HID | CDC [LSB] + */ +#define _PID_MAP(itf, n) ((CFG_TUD_##itf) << (n)) +#define USB_PID \ + (0x4000 | _PID_MAP(CDC, 0) | _PID_MAP(HID, 2) | _PID_MAP(MIDI, 3) | \ + _PID_MAP(VENDOR, 4)) + +#define USB_VID 0xCafe +#define USB_BCD 0x0200 + +//--------------------------------------------------------------------+ +// Device Descriptors +//--------------------------------------------------------------------+ + +// Invoked when received GET DEVICE DESCRIPTOR +// Application return pointer to descriptor +uint8_t const *tud_descriptor_device_cb(void) { + tu_static tusb_desc_device_t const desc_device = { + .bLength = sizeof(tusb_desc_device_t), + .bDescriptorType = TUSB_DESC_DEVICE, + .bcdUSB = USB_BCD, + + // Use Interface Association Descriptor (IAD) for CDC + // As required by USB Specs IAD's subclass must be common class (2) and + // protocol must be IAD (1) + .bDeviceClass = TUSB_CLASS_MISC, + .bDeviceSubClass = MISC_SUBCLASS_COMMON, + .bDeviceProtocol = MISC_PROTOCOL_IAD, + + .bMaxPacketSize0 = CFG_TUD_ENDPOINT0_SIZE, + + .idVendor = USB_VID, + .idProduct = USB_PID, + .bcdDevice = 0x0100, + + .iManufacturer = 0x01, + .iProduct = 0x02, + .iSerialNumber = 0x03, + + .bNumConfigurations = 0x01}; + + return (uint8_t const *)&desc_device; +} + +//--------------------------------------------------------------------+ +// Configuration Descriptor +//--------------------------------------------------------------------+ + +enum { ITF_NUM_CDC = 0, ITF_NUM_CDC_DATA, ITF_NUM_TOTAL }; + +#define EPNUM_CDC_NOTIF 0x81 +#define EPNUM_CDC_OUT 0x02 +#define EPNUM_CDC_IN 0x82 + +#define CONFIG_TOTAL_LEN (TUD_CONFIG_DESC_LEN + TUD_CDC_DESC_LEN) + +// full speed configuration +uint8_t const desc_fs_configuration[] = { + // Config number, interface count, string index, total length, attribute, + // power in mA + TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100), + + // Interface number, string index, EP notification address and size, EP data + // address (out, in) and size. + TUD_CDC_DESCRIPTOR(ITF_NUM_CDC, 4, EPNUM_CDC_NOTIF, 8, EPNUM_CDC_OUT, + EPNUM_CDC_IN, 64), +}; + +#if TUD_OPT_HIGH_SPEED +// Per USB specs: high speed capable device must report device_qualifier and +// other_speed_configuration + +// high speed configuration +uint8_t const desc_hs_configuration[] = { + // Config number, interface count, string index, total length, attribute, + // power in mA + TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100), + + // Interface number, string index, EP notification address and size, EP data + // address (out, in) and size. + TUD_CDC_DESCRIPTOR(ITF_NUM_CDC, 4, EPNUM_CDC_NOTIF, 8, EPNUM_CDC_OUT, + EPNUM_CDC_IN, 512), +}; + +// other speed configuration +uint8_t desc_other_speed_config[CONFIG_TOTAL_LEN]; + +// device qualifier is mostly similar to device descriptor since we don't change +// configuration based on speed +tusb_desc_device_qualifier_t const desc_device_qualifier = { + .bLength = sizeof(tusb_desc_device_qualifier_t), + .bDescriptorType = TUSB_DESC_DEVICE_QUALIFIER, + .bcdUSB = USB_BCD, + + .bDeviceClass = TUSB_CLASS_MISC, + .bDeviceSubClass = MISC_SUBCLASS_COMMON, + .bDeviceProtocol = MISC_PROTOCOL_IAD, + + .bMaxPacketSize0 = CFG_TUD_ENDPOINT0_SIZE, + .bNumConfigurations = 0x01, + .bReserved = 0x00}; + +// Invoked when received GET DEVICE QUALIFIER DESCRIPTOR request +// Application return pointer to descriptor, whose contents must exist long +// enough for transfer to complete. device_qualifier descriptor describes +// information about a high-speed capable device that would change if the device +// were operating at the other speed. If not highspeed capable stall this +// request. +uint8_t const *tud_descriptor_device_qualifier_cb(void) { + return (uint8_t const *)&desc_device_qualifier; +} + +// Invoked when received GET OTHER SEED CONFIGURATION DESCRIPTOR request +// Application return pointer to descriptor, whose contents must exist long +// enough for transfer to complete Configuration descriptor in the other speed +// e.g if high speed then this is for full speed and vice versa +uint8_t const *tud_descriptor_other_speed_configuration_cb(uint8_t index) { + (void)index; // for multiple configurations + + // if link speed is high return fullspeed config, and vice versa + // Note: the descriptor type is OHER_SPEED_CONFIG instead of CONFIG + memcpy(desc_other_speed_config, + (tud_speed_get() == TUSB_SPEED_HIGH) ? desc_fs_configuration + : desc_hs_configuration, + CONFIG_TOTAL_LEN); + + desc_other_speed_config[1] = TUSB_DESC_OTHER_SPEED_CONFIG; + + return desc_other_speed_config; +} + +#endif // highspeed + +// Invoked when received GET CONFIGURATION DESCRIPTOR +// Application return pointer to descriptor +// Descriptor contents must exist long enough for transfer to complete +uint8_t const *tud_descriptor_configuration_cb(uint8_t index) { + (void)index; // for multiple configurations + +#if TUD_OPT_HIGH_SPEED + // Although we are highspeed, host may be fullspeed. + return (tud_speed_get() == TUSB_SPEED_HIGH) ? desc_hs_configuration + : desc_fs_configuration; +#else + return desc_fs_configuration; +#endif +} + +//--------------------------------------------------------------------+ +// String Descriptors +//--------------------------------------------------------------------+ + +// array of pointer to string descriptors +char const *string_desc_arr[] = { + (const char[]){0x09, 0x04}, // 0: is supported language is English (0x0409) + "TinyUSB", // 1: Manufacturer + "TinyUSB Device", // 2: Product + "123456789012", // 3: Serials, should use chip ID + "TinyUSB CDC", // 4: CDC Interface +}; + +tu_static uint16_t _desc_str[32]; + +// Invoked when received GET STRING DESCRIPTOR request +// Application return pointer to descriptor, whose contents must exist long +// enough for transfer to complete +uint16_t const *tud_descriptor_string_cb(uint8_t index, uint16_t langid) { + (void)langid; + + uint8_t chr_count; + + if (index == 0) { + memcpy(&_desc_str[1], string_desc_arr[0], 2); + chr_count = 1; + } else { + // Note: the 0xEE index string is a Microsoft OS 1.0 Descriptors. + // https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/microsoft-defined-usb-descriptors + + if (!(index < sizeof(string_desc_arr) / sizeof(string_desc_arr[0]))) + return NULL; + + const char *str = string_desc_arr[index]; + + // Cap at max char + chr_count = (uint8_t)strlen(str); + if (chr_count > 31) + chr_count = 31; + + // Convert ASCII string into UTF-16 + for (uint8_t i = 0; i < chr_count; i++) { + _desc_str[1 + i] = str[i]; + } + } + + // first byte is length (including header), second byte is string type + _desc_str[0] = (uint16_t)((TUSB_DESC_STRING << 8) | (2 * chr_count + 2)); + + return _desc_str; +} |