executor: add support for USB fuzzing on NetBSD

10 files changed, 1597 insertions, 18 deletions

diff --git a/executor/common_bsd.h b/executor/common_bsd.h
index c818d802e..4ed81a3a3 100644
--- a/executor/common_bsd.h
+++ b/executor/common_bsd.h
@@ -11,6 +11,17 @@
 #include <string.h>
 #include <sys/syscall.h>
 
+#if GOOS_netbsd
+#if SYZ_EXECUTOR || __NR_syz_usb_connect
+#include "common_usb_netbsd.h"
+static void setup_usb(void)
+{
+	if (chmod("/dev/vhci", 0666))
+		fail("failed to chmod /dev/vhci");
+}
+#endif
+#endif
+
 #if GOOS_openbsd
 
 #define __syscall syscall
diff --git a/executor/common_linux.h b/executor/common_linux.h
index 2a58d735e..ec4dba32c 100644
--- a/executor/common_linux.h
+++ b/executor/common_linux.h
@@ -1463,7 +1463,7 @@ static long syz_extract_tcp_res(volatile long a0, volatile long a1, volatile lon
 #include <sys/stat.h>
 #include <sys/types.h>
 
-#include "common_usb.h"
+#include "common_usb_linux.h"
 #endif
 
 #if SYZ_EXECUTOR || __NR_syz_open_dev
diff --git a/executor/common_usb.h b/executor/common_usb.h
index f14d6b9b1..3996b0e1c 100644
--- a/executor/common_usb.h
+++ b/executor/common_usb.h
@@ -684,7 +684,7 @@ static bool lookup_connect_response_out_generic(int fd, const struct vusb_connec
 }
 #endif // SYZ_EXECUTOR || __NR_syz_usb_connect
 
-#if SYZ_EXECUTOR || __NR_syz_usb_connect_ath9k
+#if GOOS_linux && (SYZ_EXECUTOR || __NR_syz_usb_connect_ath9k)
 
 // drivers/net/wireless/ath/ath9k/hif_usb.h
 #define ATH9K_FIRMWARE_DOWNLOAD 0x30
@@ -721,7 +721,7 @@ static bool lookup_connect_response_out_ath9k(int fd, const struct vusb_connect_
 
 #endif // SYZ_EXECUTOR || __NR_syz_usb_connect_ath9k
 
-#if SYZ_EXECUTOR || __NR_syz_usb_control_io
+#if GOOS_linux && (SYZ_EXECUTOR || __NR_syz_usb_control_io)
 
 struct vusb_descriptor {
 	uint8 req_type;
@@ -820,9 +820,3 @@ static bool lookup_control_response(const struct vusb_descriptors* descs, const
 }
 
 #endif // SYZ_EXECUTOR || __NR_syz_usb_control_io
-
-#if GOOS_linux
-#include "common_usb_linux.h"
-#else
-#error "unknown OS"
-#endif // GOOS_linux
diff --git a/executor/common_usb_linux.h b/executor/common_usb_linux.h
index 935b30df2..f9d30d33b 100644
--- a/executor/common_usb_linux.h
+++ b/executor/common_usb_linux.h
@@ -5,6 +5,8 @@
 
 // Linux-specific implementation of syz_usb_* pseudo-syscalls.
 
+#include "common_usb.h"
+
 #define UDC_NAME_LENGTH_MAX 128
 
 struct usb_raw_init {
diff --git a/executor/common_usb_netbsd.h b/executor/common_usb_netbsd.h
new file mode 100644
index 000000000..35a9bf730
--- /dev/null
+++ b/executor/common_usb_netbsd.h
@@ -0,0 +1,379 @@
+// Copyright 2020 syzkaller project authors. All rights reserved.
+// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+// This file is shared between executor and csource package.
+
+// NetBSD-specific implementation of syz_usb_* pseudo-syscalls.
+
+#include <dev/usb/usb.h>
+#include <dev/usb/usbhid.h>
+#include <dev/usb/vhci.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+
+/* -------------------------------------------------------------------------- */
+
+/*
+ * Redefinitions to match the linux types used in common_usb.h.
+ */
+
+struct usb_endpoint_descriptor {
+	uint8_t bLength;
+	uint8_t bDescriptorType;
+	uint8_t bEndpointAddress;
+	uint8_t bmAttributes;
+	uint16_t wMaxPacketSize;
+	uint8_t bInterval;
+	uint8_t bRefresh;
+	uint8_t bSynchAddress;
+} __attribute__((packed));
+
+struct usb_device_descriptor {
+	uint8_t bLength;
+	uint8_t bDescriptorType;
+	uint16_t bcdUSB;
+	uint8_t bDeviceClass;
+	uint8_t bDeviceSubClass;
+	uint8_t bDeviceProtocol;
+	uint8_t bMaxPacketSize0;
+	uint16_t idVendor;
+	uint16_t idProduct;
+	uint16_t bcdDevice;
+	uint8_t iManufacturer;
+	uint8_t iProduct;
+	uint8_t iSerialNumber;
+	uint8_t bNumConfigurations;
+} __attribute__((packed));
+
+struct usb_config_descriptor {
+	uint8_t bLength;
+	uint8_t bDescriptorType;
+
+	uint16_t wTotalLength;
+	uint8_t bNumInterfaces;
+	uint8_t bConfigurationValue;
+	uint8_t iConfiguration;
+	uint8_t bmAttributes;
+	uint8_t bMaxPower;
+} __attribute__((packed));
+
+struct usb_interface_descriptor {
+	uint8_t bLength;
+	uint8_t bDescriptorType;
+	uint8_t bInterfaceNumber;
+	uint8_t bAlternateSetting;
+	uint8_t bNumEndpoints;
+	uint8_t bInterfaceClass;
+	uint8_t bInterfaceSubClass;
+	uint8_t bInterfaceProtocol;
+	uint8_t iInterface;
+} __attribute__((packed));
+
+struct usb_ctrlrequest {
+	uint8_t bRequestType;
+	uint8_t bRequest;
+	uint16_t wValue;
+	uint16_t wIndex;
+	uint16_t wLength;
+} __attribute__((packed));
+
+struct usb_qualifier_descriptor {
+	uint8_t bLength;
+	uint8_t bDescriptorType;
+	uint16_t bcdUSB;
+	uint8_t bDeviceClass;
+	uint8_t bDeviceSubClass;
+	uint8_t bDeviceProtocol;
+	uint8_t bMaxPacketSize0;
+	uint8_t bNumConfigurations;
+	uint8_t bRESERVED;
+} __attribute__((packed));
+
+#define USB_TYPE_MASK (0x03 << 5)
+#define USB_TYPE_STANDARD (0x00 << 5)
+#define USB_TYPE_CLASS (0x01 << 5)
+#define USB_TYPE_VENDOR (0x02 << 5)
+#define USB_TYPE_RESERVED (0x03 << 5)
+
+#define USB_DT_DEVICE 0x01
+#define USB_DT_CONFIG 0x02
+#define USB_DT_STRING 0x03
+#define USB_DT_INTERFACE 0x04
+#define USB_DT_ENDPOINT 0x05
+#define USB_DT_DEVICE_QUALIFIER 0x06
+#define USB_DT_OTHER_SPEED_CONFIG 0x07
+#define USB_DT_INTERFACE_POWER 0x08
+#define USB_DT_OTG 0x09
+#define USB_DT_DEBUG 0x0a
+#define USB_DT_INTERFACE_ASSOCIATION 0x0b
+#define USB_DT_SECURITY 0x0c
+#define USB_DT_KEY 0x0d
+#define USB_DT_ENCRYPTION_TYPE 0x0e
+#define USB_DT_BOS 0x0f
+#define USB_DT_DEVICE_CAPABILITY 0x10
+#define USB_DT_WIRELESS_ENDPOINT_COMP 0x11
+#define USB_DT_WIRE_ADAPTER 0x21
+#define USB_DT_RPIPE 0x22
+#define USB_DT_CS_RADIO_CONTROL 0x23
+#define USB_DT_PIPE_USAGE 0x24
+#define USB_DT_SS_ENDPOINT_COMP 0x30
+#define USB_DT_SSP_ISOC_ENDPOINT_COMP 0x31
+
+#define USB_REQ_GET_STATUS 0x00
+#define USB_REQ_CLEAR_FEATURE 0x01
+#define USB_REQ_SET_FEATURE 0x03
+#define USB_REQ_SET_ADDRESS 0x05
+#define USB_REQ_GET_DESCRIPTOR 0x06
+#define USB_REQ_SET_DESCRIPTOR 0x07
+#define USB_REQ_GET_CONFIGURATION 0x08
+#define USB_REQ_SET_CONFIGURATION 0x09
+#define USB_REQ_GET_INTERFACE 0x0A
+#define USB_REQ_SET_INTERFACE 0x0B
+#define USB_REQ_SYNCH_FRAME 0x0C
+#define USB_REQ_SET_SEL 0x30
+#define USB_REQ_SET_ISOCH_DELAY 0x31
+
+#define USB_REQ_SET_ENCRYPTION 0x0D
+#define USB_REQ_GET_ENCRYPTION 0x0E
+#define USB_REQ_RPIPE_ABORT 0x0E
+#define USB_REQ_SET_HANDSHAKE 0x0F
+#define USB_REQ_RPIPE_RESET 0x0F
+#define USB_REQ_GET_HANDSHAKE 0x10
+#define USB_REQ_SET_CONNECTION 0x11
+#define USB_REQ_SET_SECURITY_DATA 0x12
+#define USB_REQ_GET_SECURITY_DATA 0x13
+#define USB_REQ_SET_WUSB_DATA 0x14
+#define USB_REQ_LOOPBACK_DATA_WRITE 0x15
+#define USB_REQ_LOOPBACK_DATA_READ 0x16
+#define USB_REQ_SET_INTERFACE_DS 0x17
+
+#define USB_REQ_GET_PARTNER_PDO 20
+#define USB_REQ_GET_BATTERY_STATUS 21
+#define USB_REQ_SET_PDO 22
+#define USB_REQ_GET_VDM 23
+#define USB_REQ_SEND_VDM 24
+
+#include "common_usb.h"
+
+/* -------------------------------------------------------------------------- */
+
+static int vhci_open(void)
+{
+	return open("/dev/vhci", O_RDWR);
+}
+
+static int vhci_setport(int fd, u_int port)
+{
+	struct vhci_ioc_set_port args;
+
+	args.port = port;
+	return ioctl(fd, VHCI_IOC_SET_PORT, &args);
+}
+
+static int vhci_usb_attach(int fd)
+{
+	return ioctl(fd, VHCI_IOC_USB_ATTACH, NULL);
+}
+
+static int vhci_usb_recv(int fd, void* buf, size_t size)
+{
+	uint8_t* ptr = (uint8_t*)buf;
+	ssize_t done;
+
+	while (1) {
+		done = read(fd, ptr, size);
+		if (done < 0)
+			return -1;
+		if ((size_t)done == size)
+			return 0;
+		size -= done;
+		ptr += done;
+	}
+}
+
+static int vhci_usb_send(int fd, void* buf, size_t size)
+{
+	uint8_t* ptr = (uint8_t*)buf;
+	ssize_t done;
+
+	while (1) {
+		done = write(fd, ptr, size);
+		if (done <= 0)
+			return -1;
+		if ((size_t)done == size)
+			return 0;
+		size -= done;
+		ptr += done;
+	}
+}
+
+/* -------------------------------------------------------------------------- */
+
+static volatile long syz_usb_connect_impl(uint64 speed, uint64 dev_len,
+					  const char* dev, const struct vusb_connect_descriptors* descs,
+					  lookup_connect_out_response_t lookup_connect_response_out)
+{
+	struct usb_device_index* index;
+	int portnum, fd, rv;
+	bool done;
+
+	portnum = procid + 1;
+
+	debug("syz_usb_connect: dev: %p\n", dev);
+	if (!dev) {
+		debug("syz_usb_connect: dev is null\n");
+		return -1;
+	}
+	if (portnum != 1) {
+		/* For now, we support only one proc. */
+		debug("syz_usb_connect: not proc1 %d\n", (int)procid);
+		return -1;
+	}
+
+	debug("syz_usb_connect: device data:\n");
+	debug_dump_data(dev, dev_len);
+
+	fd = vhci_open();
+	if (fd < 0) {
+		debug("syz_usb_connect: vhci_open failed with %d\n", fd);
+		return -1;
+	}
+	debug("syz_usb_connect: vhci_open success\n");
+
+	index = add_usb_index(fd, dev, dev_len);
+	if (!index) {
+		debug("syz_usb_connect: add_usb_index failed\n");
+		goto err;
+	}
+	debug("syz_usb_connect: add_usb_index success\n");
+
+#if USB_DEBUG
+	NONFAILING(analyze_usb_device(index));
+#endif
+
+	rv = vhci_setport(fd, portnum);
+	if (rv != 0) {
+		debug("syz_usb_connect: vhci_setport failed with %d\n", rv);
+		goto err;
+	}
+	debug("syz_usb_connect: vhci_setport success\n");
+
+	rv = vhci_usb_attach(fd);
+	if (rv != 0) {
+		debug("syz_usb_connect: vhci_usb_attach failed with %d\n", rv);
+		goto err;
+	}
+	debug("syz_usb_connect: vhci_usb_attach success\n");
+
+	done = false;
+	while (!done) {
+		vhci_request_t req;
+
+		rv = vhci_usb_recv(fd, &req, sizeof(req));
+		if (rv != 0) {
+			debug("syz_usb_connect: vhci_usb_recv failed with %d\n", errno);
+			goto err;
+		}
+		if (req.type != VHCI_REQ_CTRL) {
+			debug("syz_usb_connect: received non-control transfer\n");
+			goto err;
+		}
+
+		debug("syz_usb_connect: bReqType: 0x%x (%s), bReq: 0x%x, wVal: 0x%x, wIdx: 0x%x, wLen: %d\n",
+		      req.u.ctrl.bmRequestType, (req.u.ctrl.bmRequestType & UE_DIR_IN) ? "IN" : "OUT",
+		      req.u.ctrl.bRequest, UGETW(req.u.ctrl.wValue), UGETW(req.u.ctrl.wIndex), UGETW(req.u.ctrl.wLength));
+
+#if USB_DEBUG
+		analyze_control_request(fd, &req.u.ctrl);
+#endif
+
+		char* response_data = NULL;
+		uint32 response_length = 0;
+		char data[4096];
+
+		if (req.u.ctrl.bmRequestType & UE_DIR_IN) {
+			bool response_found = false;
+			NONFAILING(response_found = lookup_connect_response_in(fd, descs, (const usb_ctrlrequest*)&req.u.ctrl, &response_data, &response_length));
+			if (!response_found) {
+				debug("syz_usb_connect: unknown control IN request\n");
+				goto err;
+			}
+		} else {
+			if (!lookup_connect_response_out(fd, descs, (const usb_ctrlrequest*)&req.u.ctrl, &done)) {
+				debug("syz_usb_connect: unknown control OUT request\n");
+				goto err;
+			}
+			response_data = NULL;
+			response_length = UGETW(req.u.ctrl.wLength);
+		}
+
+		if ((req.u.ctrl.bmRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD &&
+		    req.u.ctrl.bRequest == USB_REQ_SET_CONFIGURATION) {
+			/* TODO: possibly revisit */
+		}
+
+		if (response_length > sizeof(data))
+			response_length = 0;
+		if ((uint32_t)UGETW(req.u.ctrl.wLength) < response_length)
+			response_length = UGETW(req.u.ctrl.wLength);
+
+		if (response_data)
+			memcpy(data, response_data, response_length);
+		else
+			memset(data, 0, response_length);
+
+		if (req.u.ctrl.bmRequestType & UE_DIR_IN) {
+			debug("syz_usb_connect: writing %d bytes\n", response_length);
+			if (response_length > 0) {
+				vhci_response_t res;
+				res.size = response_length;
+				rv = vhci_usb_send(fd, &res, sizeof(res));
+				if (rv == 0)
+					rv = vhci_usb_send(fd, data, response_length);
+			}
+		} else {
+			rv = vhci_usb_recv(fd, data, response_length);
+			debug("syz_usb_connect: read %d bytes\n", response_length);
+			debug_dump_data(&data[0], response_length);
+		}
+		if (rv < 0) {
+			debug("syz_usb_connect: usb_raw_ep0_read/write failed with %d\n", rv);
+			goto err;
+		}
+	}
+
+	sleep_ms(200);
+	debug("syz_usb_connect: configured\n");
+	return fd;
+
+err:
+	close(fd);
+	return -1;
+}
+
+#if SYZ_EXECUTOR || __NR_syz_usb_connect
+static volatile long syz_usb_connect(volatile long a0, volatile long a1,
+				     volatile long a2, volatile long a3)
+{
+	uint64 speed = a0;
+	uint64 dev_len = a1;
+	const char* dev = (const char*)a2;
+	const struct vusb_connect_descriptors* descs = (const struct vusb_connect_descriptors*)a3;
+
+	return syz_usb_connect_impl(speed, dev_len, dev, descs,
+				    &lookup_connect_response_out_generic);
+}
+#endif // SYZ_EXECUTOR || __NR_syz_usb_connect
+
+#if SYZ_EXECUTOR || __NR_syz_usb_disconnect
+static volatile long syz_usb_disconnect(volatile long a0)
+{
+	int fd = a0;
+
+	int rv = close(fd);
+
+	sleep_ms(200);
+
+	return rv;
+}
+#endif // SYZ_EXECUTOR || __NR_syz_usb_disconnect
diff --git a/executor/executor_bsd.h b/executor/executor_bsd.h
index 39a4d732e..00de87d06 100644
--- a/executor/executor_bsd.h
+++ b/executor/executor_bsd.h
@@ -156,3 +156,15 @@ static bool cover_check(uint64 pc)
 #else
 #include "nocover.h"
 #endif
+
+#if GOOS_netbsd
+#define SYZ_HAVE_FEATURES 1
+static feature_t features[] = {
+    {"usb", setup_usb},
+};
+
+static void setup_machine(void)
+{
+	/* nothing */
+}
+#endif
diff --git a/pkg/csource/gen.go b/pkg/csource/gen.go
index b32950dd3..cc96d60c8 100644
--- a/pkg/csource/gen.go
+++ b/pkg/csource/gen.go
@@ -32,8 +32,9 @@ func main() {
 		"common_test.h",
 		"common_kvm_amd64.h",
 		"common_kvm_arm64.h",
-		"common_usb.h",
 		"common_usb_linux.h",
+		"common_usb_netbsd.h",
+		"common_usb.h",
 		"android/android_seccomp.h",
 		"kvm.h",
 		"kvm.S.h",
diff --git a/pkg/csource/generated.go b/pkg/csource/generated.go
index 654f80ac3..c9a42bfa1 100644
--- a/pkg/csource/generated.go
+++ b/pkg/csource/generated.go
@@ -409,6 +409,1165 @@ void child()
 #include <string.h>
 #include <sys/syscall.h>
 
+#if GOOS_netbsd
+#if SYZ_EXECUTOR || __NR_syz_usb_connect
+
+#include <dev/usb/usb.h>
+#include <dev/usb/usbhid.h>
+#include <dev/usb/vhci.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+
+/* -------------------------------------------------------------------------- */
+
+/*
+ * Redefinitions to match the linux types used in common_usb.h.
+ */
+
+struct usb_endpoint_descriptor {
+	uint8_t bLength;
+	uint8_t bDescriptorType;
+	uint8_t bEndpointAddress;
+	uint8_t bmAttributes;
+	uint16_t wMaxPacketSize;
+	uint8_t bInterval;
+	uint8_t bRefresh;
+	uint8_t bSynchAddress;
+} __attribute__((packed));
+
+struct usb_device_descriptor {
+	uint8_t bLength;
+	uint8_t bDescriptorType;
+	uint16_t bcdUSB;
+	uint8_t bDeviceClass;
+	uint8_t bDeviceSubClass;
+	uint8_t bDeviceProtocol;
+	uint8_t bMaxPacketSize0;
+	uint16_t idVendor;
+	uint16_t idProduct;
+	uint16_t bcdDevice;
+	uint8_t iManufacturer;
+	uint8_t iProduct;
+	uint8_t iSerialNumber;
+	uint8_t bNumConfigurations;
+} __attribute__((packed));
+
+struct usb_config_descriptor {
+	uint8_t bLength;
+	uint8_t bDescriptorType;
+
+	uint16_t wTotalLength;
+	uint8_t bNumInterfaces;
+	uint8_t bConfigurationValue;
+	uint8_t iConfiguration;
+	uint8_t bmAttributes;
+	uint8_t bMaxPower;
+} __attribute__((packed));
+
+struct usb_interface_descriptor {
+	uint8_t bLength;
+	uint8_t bDescriptorType;
+	uint8_t bInterfaceNumber;
+	uint8_t bAlternateSetting;
+	uint8_t bNumEndpoints;
+	uint8_t bInterfaceClass;
+	uint8_t bInterfaceSubClass;
+	uint8_t bInterfaceProtocol;
+	uint8_t iInterface;
+} __attribute__((packed));
+
+struct usb_ctrlrequest {
+	uint8_t bRequestType;
+	uint8_t bRequest;
+	uint16_t wValue;
+	uint16_t wIndex;
+	uint16_t wLength;
+} __attribute__((packed));
+
+struct usb_qualifier_descriptor {
+	uint8_t bLength;
+	uint8_t bDescriptorType;
+	uint16_t bcdUSB;
+	uint8_t bDeviceClass;
+	uint8_t bDeviceSubClass;
+	uint8_t bDeviceProtocol;
+	uint8_t bMaxPacketSize0;
+	uint8_t bNumConfigurations;
+	uint8_t bRESERVED;
+} __attribute__((packed));
+
+#define USB_TYPE_MASK (0x03 << 5)
+#define USB_TYPE_STANDARD (0x00 << 5)
+#define USB_TYPE_CLASS (0x01 << 5)
+#define USB_TYPE_VENDOR (0x02 << 5)
+#define USB_TYPE_RESERVED (0x03 << 5)
+
+#define USB_DT_DEVICE 0x01
+#define USB_DT_CONFIG 0x02
+#define USB_DT_STRING 0x03
+#define USB_DT_INTERFACE 0x04
+#define USB_DT_ENDPOINT 0x05
+#define USB_DT_DEVICE_QUALIFIER 0x06
+#define USB_DT_OTHER_SPEED_CONFIG 0x07
+#define USB_DT_INTERFACE_POWER 0x08
+#define USB_DT_OTG 0x09
+#define USB_DT_DEBUG 0x0a
+#define USB_DT_INTERFACE_ASSOCIATION 0x0b
+#define USB_DT_SECURITY 0x0c
+#define USB_DT_KEY 0x0d
+#define USB_DT_ENCRYPTION_TYPE 0x0e
+#define USB_DT_BOS 0x0f
+#define USB_DT_DEVICE_CAPABILITY 0x10
+#define USB_DT_WIRELESS_ENDPOINT_COMP 0x11
+#define USB_DT_WIRE_ADAPTER 0x21
+#define USB_DT_RPIPE 0x22
+#define USB_DT_CS_RADIO_CONTROL 0x23
+#define USB_DT_PIPE_USAGE 0x24
+#define USB_DT_SS_ENDPOINT_COMP 0x30
+#define USB_DT_SSP_ISOC_ENDPOINT_COMP 0x31
+
+#define USB_REQ_GET_STATUS 0x00
+#define USB_REQ_CLEAR_FEATURE 0x01
+#define USB_REQ_SET_FEATURE 0x03
+#define USB_REQ_SET_ADDRESS 0x05
+#define USB_REQ_GET_DESCRIPTOR 0x06
+#define USB_REQ_SET_DESCRIPTOR 0x07
+#define USB_REQ_GET_CONFIGURATION 0x08
+#define USB_REQ_SET_CONFIGURATION 0x09
+#define USB_REQ_GET_INTERFACE 0x0A
+#define USB_REQ_SET_INTERFACE 0x0B
+#define USB_REQ_SYNCH_FRAME 0x0C
+#define USB_REQ_SET_SEL 0x30
+#define USB_REQ_SET_ISOCH_DELAY 0x31
+
+#define USB_REQ_SET_ENCRYPTION 0x0D
+#define USB_REQ_GET_ENCRYPTION 0x0E
+#define USB_REQ_RPIPE_ABORT 0x0E
+#define USB_REQ_SET_HANDSHAKE 0x0F
+#define USB_REQ_RPIPE_RESET 0x0F
+#define USB_REQ_GET_HANDSHAKE 0x10
+#define USB_REQ_SET_CONNECTION 0x11
+#define USB_REQ_SET_SECURITY_DATA 0x12
+#define USB_REQ_GET_SECURITY_DATA 0x13
+#define USB_REQ_SET_WUSB_DATA 0x14
+#define USB_REQ_LOOPBACK_DATA_WRITE 0x15
+#define USB_REQ_LOOPBACK_DATA_READ 0x16
+#define USB_REQ_SET_INTERFACE_DS 0x17
+
+#define USB_REQ_GET_PARTNER_PDO 20
+#define USB_REQ_GET_BATTERY_STATUS 21
+#define USB_REQ_SET_PDO 22
+#define USB_REQ_GET_VDM 23
+#define USB_REQ_SEND_VDM 24
+
+#define USB_MAX_IFACE_NUM 4
+#define USB_MAX_EP_NUM 32
+#define USB_MAX_FDS 6
+
+struct usb_endpoint_index {
+	struct usb_endpoint_descriptor desc;
+	int handle;
+};
+
+struct usb_iface_index {
+	struct usb_interface_descriptor* iface;
+	uint8 bInterfaceNumber;
+	uint8 bAlternateSetting;
+	uint8 bInterfaceClass;
+	struct usb_endpoint_index eps[USB_MAX_EP_NUM];
+	int eps_num;
+};
+
+struct usb_device_index {
+	struct usb_device_descriptor* dev;
+	struct usb_config_descriptor* config;
+	uint8 bDeviceClass;
+	uint8 bMaxPower;
+	int config_length;
+	struct usb_iface_index ifaces[USB_MAX_IFACE_NUM];
+	int ifaces_num;
+	int iface_cur;
+};
+
+struct usb_info {
+	int fd;
+	struct usb_device_index index;
+};
+
+static struct usb_info usb_devices[USB_MAX_FDS];
+static int usb_devices_num;
+
+static bool parse_usb_descriptor(const char* buffer, size_t length, struct usb_device_index* index)
+{
+	if (length < sizeof(*index->dev) + sizeof(*index->config))
+		return false;
+
+	memset(index, 0, sizeof(*index));
+
+	index->dev = (struct usb_device_descriptor*)buffer;
+	index->config = (struct usb_config_descriptor*)(buffer + sizeof(*index->dev));
+	index->bDeviceClass = index->dev->bDeviceClass;
+	index->bMaxPower = index->config->bMaxPower;
+	index->config_length = length - sizeof(*index->dev);
+	index->iface_cur = -1;
+	size_t offset = 0;
+
+	while (true) {
+		if (offset + 1 >= length)
+			break;
+		uint8 desc_length = buffer[offset];
+		uint8 desc_type = buffer[offset + 1];
+		if (desc_length <= 2)
+			break;
+		if (offset + desc_length > length)
+			break;
+		if (desc_type == USB_DT_INTERFACE && index->ifaces_num < USB_MAX_IFACE_NUM) {
+			struct usb_interface_descriptor* iface = (struct usb_interface_descriptor*)(buffer + offset);
+			debug("parse_usb_descriptor: found interface #%u (%d, %d) at %p\n",
+			      index->ifaces_num, iface->bInterfaceNumber, iface->bAlternateSetting, iface);
+			index->ifaces[index->ifaces_num].iface = iface;
+			index->ifaces[index->ifaces_num].bInterfaceNumber = iface->bInterfaceNumber;
+			index->ifaces[index->ifaces_num].bAlternateSetting = iface->bAlternateSetting;
+			index->ifaces[index->ifaces_num].bInterfaceClass = iface->bInterfaceClass;
+			index->ifaces_num++;
+		}
+		if (desc_type == USB_DT_ENDPOINT && index->ifaces_num > 0) {
+			struct usb_iface_index* iface = &index->ifaces[index->ifaces_num - 1];
+			debug("parse_usb_descriptor: found endpoint #%u at %p\n", iface->eps_num, buffer + offset);
+			if (iface->eps_num < USB_MAX_EP_NUM) {
+				memcpy(&iface->eps[iface->eps_num].desc, buffer + offset, sizeof(iface->eps[iface->eps_num].desc));
+				iface->eps_num++;
+			}
+		}
+		offset += desc_length;
+	}
+
+	return true;
+}
+
+static struct usb_device_index* add_usb_index(int fd, const char* dev, size_t dev_len)
+{
+	int i = __atomic_fetch_add(&usb_devices_num, 1, __ATOMIC_RELAXED);
+	if (i >= USB_MAX_FDS)
+		return NULL;
+
+	int rv = 0;
+	NONFAILING(rv = parse_usb_descriptor(dev, dev_len, &usb_devices[i].index));
+	if (!rv)
+		return NULL;
+
+	__atomic_store_n(&usb_devices[i].fd, fd, __ATOMIC_RELEASE);
+	return &usb_devices[i].index;
+}
+
+static struct usb_device_index* lookup_usb_index(int fd)
+{
+	int i;
+	for (i = 0; i < USB_MAX_FDS; i++) {
+		if (__atomic_load_n(&usb_devices[i].fd, __ATOMIC_ACQUIRE) == fd) {
+			return &usb_devices[i].index;
+		}
+	}
+	return NULL;
+}
+
+#if USB_DEBUG
+
+#include <linux/hid.h>
+#include <linux/usb/audio.h>
+#include <linux/usb/cdc.h>
+#include <linux/usb/ch11.h>
+#include <linux/usb/ch9.h>
+#define USBLP_REQ_GET_ID 0x00
+#define USBLP_REQ_GET_STATUS 0x01
+#define USBLP_REQ_RESET 0x02
+
+const char* usb_class_to_string(unsigned value)
+{
+	switch (value) {
+	case USB_CLASS_PER_INTERFACE:
+		return "USB_CLASS_PER_INTERFACE";
+	case USB_CLASS_AUDIO:
+		return "USB_CLASS_AUDIO";
+	case USB_CLASS_COMM:
+		return "USB_CLASS_COMM";
+	case USB_CLASS_HID:
+		return "USB_CLASS_HID";
+	case USB_CLASS_PHYSICAL:
+		return "USB_CLASS_PHYSICAL";
+	case USB_CLASS_STILL_IMAGE:
+		return "USB_CLASS_STILL_IMAGE";
+	case USB_CLASS_PRINTER:
+		return "USB_CLASS_PRINTER";
+	case USB_CLASS_MASS_STORAGE:
+		return "USB_CLASS_MASS_STORAGE";
+	case USB_CLASS_HUB:
+		return "USB_CLASS_HUB";
+	case USB_CLASS_CDC_DATA:
+		return "USB_CLASS_CDC_DATA";
+	case USB_CLASS_CSCID:
+		return "USB_CLASS_CSCID";
+	case USB_CLASS_CONTENT_SEC:
+		return "USB_CLASS_CONTENT_SEC";
+	case USB_CLASS_VIDEO:
+		return "USB_CLASS_VIDEO";
+	case USB_CLASS_WIRELESS_CONTROLLER:
+		return "USB_CLASS_WIRELESS_CONTROLLER";
+	case USB_CLASS_MISC:
+		return "USB_CLASS_MISC";
+	case USB_CLASS_APP_SPEC:
+		return "USB_CLASS_APP_SPEC";
+	case USB_CLASS_VENDOR_SPEC:
+		return "USB_CLASS_VENDOR_SPEC";
+	}
+	return "unknown";
+}
+static void analyze_usb_device(struct usb_device_index* index)
+{
+	debug("analyze_usb_device: idVendor = %04x\n", (unsigned)index->dev->idVendor);
+	debug("analyze_usb_device: idProduct = %04x\n", (unsigned)index->dev->idProduct);
+
+	debug("analyze_usb_device: bDeviceClass = %x (%s)\n", (unsigned)index->dev->bDeviceClass,
+	      usb_class_to_string(index->dev->bDeviceClass));
+	debug("analyze_usb_device: bDeviceSubClass = %x\n", (unsigned)index->dev->bDeviceSubClass);
+	debug("analyze_usb_device: bDeviceProtocol = %x\n", (unsigned)index->dev->bDeviceProtocol);
+
+	for (int i = 0; i < index->ifaces_num; i++) {
+		struct usb_interface_descriptor* iface = index->ifaces[i].iface;
+		debug("analyze_usb_device: interface #%d:\n", i);
+		debug("analyze_usb_device: bInterfaceClass = %x (%s)\n", (unsigned)iface->bInterfaceClass,
+		      usb_class_to_string(iface->bInterfaceClass));
+		debug("analyze_usb_device: bInterfaceSubClass = %x\n", (unsigned)iface->bInterfaceSubClass);
+		debug("analyze_usb_device: bInterfaceProtocol = %x\n", (unsigned)iface->bInterfaceProtocol);
+	}
+}
+
+static bool analyze_control_request_standard(struct usb_device_index* index, struct usb_ctrlrequest* ctrl)
+{
+	uint8 bDeviceClass = index->bDeviceClass;
+	uint8 bInterfaceClass = index->ifaces[index->iface_cur].bInterfaceClass;
+	if (bDeviceClass == USB_CLASS_HID || bInterfaceClass == USB_CLASS_HID) {
+		switch (ctrl->bRequest) {
+		case USB_REQ_GET_DESCRIPTOR:
+			debug("analyze_control_request: req = USB_REQ_GET_DESCRIPTOR\n");
+			switch (ctrl->wValue >> 8) {
+			case HID_DT_HID:
+				debug("analyze_control_request: desc = HID_DT_HID\n");
+				return true;
+			case HID_DT_REPORT:
+				debug("analyze_control_request: desc = HID_DT_REPORT\n");
+				return true;
+			case HID_DT_PHYSICAL:
+				debug("analyze_control_request: desc = HID_DT_PHYSICAL\n");
+				return false;
+			}
+		}
+	}
+
+	switch (ctrl->bRequest) {
+	case USB_REQ_GET_DESCRIPTOR:
+		debug("analyze_control_request: req = USB_REQ_GET_DESCRIPTOR\n");
+		switch (ctrl->wValue >> 8) {
+		case USB_DT_DEVICE:
+			debug("analyze_control_request: desc = USB_DT_DEVICE\n");
+			return true;
+		case USB_DT_CONFIG:
+			debug("analyze_control_request: desc = USB_DT_CONFIG, index = %d\n", (int)(ctrl->wValue & 0xff));
+			return true;
+		case USB_DT_STRING:
+			debug("analyze_control_request: desc = USB_DT_STRING\n");
+			return true;
+		case USB_DT_INTERFACE:
+			debug("analyze_control_request: desc = USB_DT_INTERFACE\n");
+			break;
+		case USB_DT_ENDPOINT:
+			debug("analyze_control_request: desc = USB_DT_ENDPOINT\n");
+			break;
+		case USB_DT_DEVICE_QUALIFIER:
+			debug("analyze_control_request: desc = USB_DT_DEVICE_QUALIFIER\n");
+			return true;
+		case USB_DT_OTHER_SPEED_CONFIG:
+			debug("analyze_control_request: desc = USB_DT_OTHER_SPEED_CONFIG\n");
+			break;
+		case USB_DT_INTERFACE_POWER:
+			debug("analyze_control_request: desc = USB_DT_INTERFACE_POWER\n");
+			break;
+		case USB_DT_OTG:
+			debug("analyze_control_request: desc = USB_DT_OTG\n");
+			break;
+		case USB_DT_DEBUG:
+			debug("analyze_control_request: desc = USB_DT_DEBUG\n");
+			break;
+		case USB_DT_INTERFACE_ASSOCIATION:
+			debug("analyze_control_request: desc = USB_DT_INTERFACE_ASSOCIATION\n");
+			break;
+		case USB_DT_SECURITY:
+			debug("analyze_control_request: desc = USB_DT_SECURITY\n");
+			break;
+		case USB_DT_KEY:
+			debug("analyze_control_request: desc = USB_DT_KEY\n");
+			break;
+		case USB_DT_ENCRYPTION_TYPE:
+			debug("analyze_control_request: desc = USB_DT_ENCRYPTION_TYPE\n");
+			break;
+		case USB_DT_BOS:
+			debug("analyze_control_request: desc = USB_DT_BOS\n");
+			return true;
+		case USB_DT_DEVICE_CAPABILITY:
+			debug("analyze_control_request: desc = USB_DT_DEVICE_CAPABILITY\n");
+			break;
+		case USB_DT_WIRELESS_ENDPOINT_COMP:
+			debug("analyze_control_request: desc = USB_DT_WIRELESS_ENDPOINT_COMP\n");
+			break;
+		case USB_DT_WIRE_ADAPTER:
+			debug("analyze_control_request: desc = USB_DT_WIRE_ADAPTER\n");
+			break;
+		case USB_DT_RPIPE:
+			debug("analyze_control_request: desc = USB_DT_RPIPE\n");
+			break;
+		case USB_DT_CS_RADIO_CONTROL:
+			debug("analyze_control_request: desc = USB_DT_CS_RADIO_CONTROL\n");
+			break;
+		case USB_DT_PIPE_USAGE:
+			debug("analyze_control_request: desc = USB_DT_PIPE_USAGE\n");
+			break;
+		case USB_DT_SS_ENDPOINT_COMP:
+			debug("analyze_control_request: desc = USB_DT_SS_ENDPOINT_COMP\n");
+			break;
+		case USB_DT_SSP_ISOC_ENDPOINT_COMP:
+			debug("analyze_control_request: desc = USB_DT_SSP_ISOC_ENDPOINT_COMP\n");
+			break;
+		default:
+			debug("analyze_control_request: desc = unknown = 0x%x\n", (int)(ctrl->wValue >> 8));
+			break;
+		}
+		break;
+	case USB_REQ_GET_STATUS:
+		debug("analyze_control_request: req = USB_REQ_GET_STATUS\n");
+		break;
+	case USB_REQ_CLEAR_FEATURE:
+		debug("analyze_control_request: req = USB_REQ_CLEAR_FEATURE\n");
+		break;
+	case USB_REQ_SET_FEATURE:
+		debug("analyze_control_request: req = USB_REQ_SET_FEATURE\n");
+		break;
+	case USB_REQ_GET_CONFIGURATION:
+		debug("analyze_control_request: req = USB_REQ_GET_CONFIGURATION\n");
+		return true;
+	case USB_REQ_SET_CONFIGURATION:
+		debug("analyze_control_request: req = USB_REQ_SET_CONFIGURATION\n");
+		break;
+	case USB_REQ_GET_INTERFACE:
+		debug("analyze_control_request: req = USB_REQ_GET_INTERFACE\n");
+		return true;
+	case USB_REQ_SET_INTERFACE:
+		debug("analyze_control_request: req = USB_REQ_SET_INTERFACE\n");
+		break;
+	default:
+		debug("analyze_control_request: req = unknown = 0x%x\n", (int)ctrl->bRequest);
+		break;
+	}
+
+	return false;
+}
+
+static bool analyze_control_request_class(struct usb_device_index* index, struct usb_ctrlrequest* ctrl)
+{
+	uint8 bDeviceClass = index->bDeviceClass;
+	uint8 bInterfaceClass = index->ifaces[index->iface_cur].bInterfaceClass;
+
+	if (bDeviceClass == USB_CLASS_HID || bInterfaceClass == USB_CLASS_HID) {
+		switch (ctrl->bRequest) {
+		case HID_REQ_GET_REPORT:
+			debug("analyze_control_request: req = HID_REQ_GET_REPORT\n");
+			return true;
+		case HID_REQ_GET_IDLE:
+			debug("analyze_control_request: req = HID_REQ_GET_IDLE\n");
+			break;
+		case HID_REQ_GET_PROTOCOL:
+			debug("analyze_control_request: req = HID_REQ_GET_PROTOCOL\n");
+			return true;
+		case HID_REQ_SET_REPORT:
+			debug("analyze_control_request: req = HID_REQ_SET_REPORT\n");
+			break;
+		case HID_REQ_SET_IDLE:
+			debug("analyze_control_request: req = HID_REQ_SET_IDLE\n");
+			break;
+		case HID_REQ_SET_PROTOCOL:
+			debug("analyze_control_request: req = HID_REQ_SET_PROTOCOL\n");
+			break;
+		}
+	}
+
+	if (bDeviceClass == USB_CLASS_AUDIO || bInterfaceClass == USB_CLASS_AUDIO) {
+		switch (ctrl->bRequest) {
+		case UAC_SET_CUR:
+			debug("analyze_control_request: req = UAC_SET_CUR\n");
+			break;
+		case UAC_GET_CUR:
+			debug("analyze_control_request: req = UAC_GET_CUR\n");
+			return true;
+		case UAC_SET_MIN:
+			debug("analyze_control_request: req = UAC_SET_MIN\n");
+			break;
+		case UAC_GET_MIN:
+			debug("analyze_control_request: req = UAC_GET_MIN\n");
+			return true;
+		case UAC_SET_MAX:
+			debug("analyze_control_request: req = UAC_SET_MAX\n");
+			break;
+		case UAC_GET_MAX:
+			debug("analyze_control_request: req = UAC_GET_MAX\n");
+			return true;
+		case UAC_SET_RES:
+			debug("analyze_control_request: req = UAC_SET_RES\n");
+			break;
+		case UAC_GET_RES:
+			debug("analyze_control_request: req = UAC_GET_RES\n");
+			return true;
+		case UAC_SET_MEM:
+			debug("analyze_control_request: req = UAC_SET_MEM\n");
+			break;
+		case UAC_GET_MEM:
+			debug("analyze_control_request: req = UAC_GET_MEM\n");
+			return true;
+		}
+	}
+
+	if (bDeviceClass == USB_CLASS_PRINTER || bInterfaceClass == USB_CLASS_PRINTER) {
+		switch (ctrl->bRequest) {
+		case USBLP_REQ_GET_ID:
+			debug("analyze_control_request: req = USBLP_REQ_GET_ID\n");
+			return true;
+		case USBLP_REQ_GET_STATUS:
+			debug("analyze_control_request: req = USBLP_REQ_GET_STATUS\n");
+			return true;
+		case USBLP_REQ_RESET:
+			debug("analyze_control_request: req = USBLP_REQ_RESET\n");
+			break;
+		}
+	}
+
+	if (bDeviceClass == USB_CLASS_HUB || bInterfaceClass == USB_CLASS_HUB) {
+		switch (ctrl->bRequest) {
+		case USB_REQ_GET_DESCRIPTOR:
+			switch (ctrl->wValue >> 8) {
+			case USB_DT_HUB:
+				debug("analyze_control_request: desc = USB_DT_HUB\n");
+				return true;
+			case USB_DT_SS_HUB:
+				debug("analyze_control_request: desc = USB_DT_SS_HUB\n");
+				return true;
+			}
+		case USB_REQ_GET_STATUS:
+			debug("analyze_control_request: req = USB_REQ_GET_STATUS\n");
+			return true;
+		case HUB_SET_DEPTH:
+			debug("analyze_control_request: req = HUB_SET_DEPTH\n");
+			break;
+		}
+	}
+
+	if (bInterfaceClass == USB_CLASS_COMM) {
+		switch (ctrl->bRequest) {
+		case USB_CDC_SEND_ENCAPSULATED_COMMAND:
+			debug("analyze_control_request: req = USB_CDC_SEND_ENCAPSULATED_COMMAND\n");
+			break;
+		case USB_CDC_GET_ENCAPSULATED_RESPONSE:
+			debug("analyze_control_request: req = USB_CDC_GET_ENCAPSULATED_RESPONSE\n");
+			break;
+		case USB_CDC_REQ_SET_LINE_CODING:
+			debug("analyze_control_request: req = USB_CDC_REQ_SET_LINE_CODING\n");
+			break;
+		case USB_CDC_REQ_GET_LINE_CODING:
+			debug("analyze_control_request: req = USB_CDC_REQ_GET_LINE_CODING\n");
+			break;
+		case USB_CDC_REQ_SET_CONTROL_LINE_STATE:
+			debug("analyze_control_request: req = USB_CDC_REQ_SET_CONTROL_LINE_STATE\n");
+			break;
+		case USB_CDC_REQ_SEND_BREAK:
+			debug("analyze_control_request: req = USB_CDC_REQ_SEND_BREAK\n");
+			break;
+		case USB_CDC_SET_ETHERNET_MULTICAST_FILTERS:
+			debug("analyze_control_request: req = USB_CDC_SET_ETHERNET_MULTICAST_FILTERS\n");
+			break;
+		case USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER:
+			debug("analyze_control_request: req = USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER\n");
+			break;
+		case USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER:
+			debug("analyze_control_request: req = USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER\n");
+			break;
+		case USB_CDC_SET_ETHERNET_PACKET_FILTER:
+			debug("analyze_control_request: req = USB_CDC_SET_ETHERNET_PACKET_FILTER\n");
+			break;
+		case USB_CDC_GET_ETHERNET_STATISTIC:
+			debug("analyze_control_request: req = USB_CDC_GET_ETHERNET_STATISTIC\n");
+			break;
+		case USB_CDC_GET_NTB_PARAMETERS:
+			debug("analyze_control_request: req = USB_CDC_GET_NTB_PARAMETERS\n");
+			return true;
+		case USB_CDC_GET_NET_ADDRESS:
+			debug("analyze_control_request: req = USB_CDC_GET_NET_ADDRESS\n");
+			break;
+		case USB_CDC_SET_NET_ADDRESS:
+			debug("analyze_control_request: req = USB_CDC_SET_NET_ADDRESS\n");
+			break;
+		case USB_CDC_GET_NTB_FORMAT:
+			debug("analyze_control_request: req = USB_CDC_GET_NTB_FORMAT\n");
+			return true;
+		case USB_CDC_SET_NTB_FORMAT:
+			debug("analyze_control_request: req = USB_CDC_SET_NTB_FORMAT\n");
+			break;
+		case USB_CDC_GET_NTB_INPUT_SIZE:
+			debug("analyze_control_request: req = USB_CDC_GET_NTB_INPUT_SIZE\n");
+			return true;
+		case USB_CDC_SET_NTB_INPUT_SIZE:
+			debug("analyze_control_request: req = USB_CDC_SET_NTB_INPUT_SIZE\n");
+			break;
+		case USB_CDC_GET_MAX_DATAGRAM_SIZE:
+			debug("analyze_control_request: req = USB_CDC_GET_MAX_DATAGRAM_SIZE\n");
+			return true;
+		case USB_CDC_SET_MAX_DATAGRAM_SIZE:
+			debug("analyze_control_request: req = USB_CDC_SET_MAX_DATAGRAM_SIZE\n");
+			break;
+		case USB_CDC_GET_CRC_MODE:
+			debug("analyze_control_request: req = USB_CDC_GET_CRC_MODE\n");
+			return true;
+		case USB_CDC_SET_CRC_MODE:
+			debug("analyze_control_request: req = USB_CDC_SET_CRC_MODE\n");
+			break;
+		}
+	}
+
+	return false;
+}
+
+static bool analyze_control_request_vendor(struct usb_device_index* index, struct usb_ctrlrequest* ctrl)
+{
+	return true;
+}
+static void analyze_control_request(int fd, struct usb_ctrlrequest* ctrl)
+{
+	struct usb_device_index* index = lookup_usb_index(fd);
+
+	if (!index)
+		return;
+
+	switch (ctrl->bRequestType & USB_TYPE_MASK) {
+	case USB_TYPE_STANDARD:
+		debug("analyze_control_request: type = USB_TYPE_STANDARD\n");
+		if (analyze_control_request_standard(index, ctrl))
+			return;
+		break;
+	case USB_TYPE_CLASS:
+		debug("analyze_control_request: type = USB_TYPE_CLASS\n");
+		if (analyze_control_request_class(index, ctrl))
+			return;
+		break;
+	case USB_TYPE_VENDOR:
+		debug("analyze_control_request: type = USB_TYPE_VENDOR\n");
+		if (analyze_control_request_vendor(index, ctrl))
+			return;
+		break;
+	}
+
+	if (ctrl->bRequestType & USB_DIR_IN) {
+		char message[128];
+		debug("analyze_control_request: unknown control request\n");
+		snprintf(&message[0], sizeof(message), "BUG: unknown control request (0x%x, 0x%x, 0x%x, 0x%x, %d)",
+			 ctrl->bRequestType, ctrl->bRequest, ctrl->wValue, ctrl->wIndex, ctrl->wLength);
+		write_file("/dev/kmsg", &message[0]);
+	}
+}
+
+#endif
+
+struct vusb_connect_string_descriptor {
+	uint32 len;
+	char* str;
+} __attribute__((packed));
+
+struct vusb_connect_descriptors {
+	uint32 qual_len;
+	char* qual;
+	uint32 bos_len;
+	char* bos;
+	uint32 strs_len;
+	struct vusb_connect_string_descriptor strs[0];
+} __attribute__((packed));
+
+static const char default_string[] = {
+    8, USB_DT_STRING,
+    's', 0, 'y', 0, 'z', 0
+};
+
+static const char default_lang_id[] = {
+    4, USB_DT_STRING,
+    0x09, 0x04
+};
+
+static bool lookup_connect_response_in(int fd, const struct vusb_connect_descriptors* descs,
+				       const struct usb_ctrlrequest* ctrl,
+				       char** response_data, uint32* response_length)
+{
+	struct usb_device_index* index = lookup_usb_index(fd);
+	uint8 str_idx;
+
+	if (!index)
+		return false;
+
+	switch (ctrl->bRequestType & USB_TYPE_MASK) {
+	case USB_TYPE_STANDARD:
+		switch (ctrl->bRequest) {
+		case USB_REQ_GET_DESCRIPTOR:
+			switch (ctrl->wValue >> 8) {
+			case USB_DT_DEVICE:
+				*response_data = (char*)index->dev;
+				*response_length = sizeof(*index->dev);
+				return true;
+			case USB_DT_CONFIG:
+				*response_data = (char*)index->config;
+				*response_length = index->config_length;
+				return true;
+			case USB_DT_STRING:
+				str_idx = (uint8)ctrl->wValue;
+				if (descs && str_idx < descs->strs_len) {
+					*response_data = descs->strs[str_idx].str;
+					*response_length = descs->strs[str_idx].len;
+					return true;
+				}
+				if (str_idx == 0) {
+					*response_data = (char*)&default_lang_id[0];
+					*response_length = default_lang_id[0];
+					return true;
+				}
+				*response_data = (char*)&default_string[0];
+				*response_length = default_string[0];
+				return true;
+			case USB_DT_BOS:
+				*response_data = descs->bos;
+				*response_length = descs->bos_len;
+				return true;
+			case USB_DT_DEVICE_QUALIFIER:
+				if (!descs->qual) {
+					struct usb_qualifier_descriptor* qual =
+					    (struct usb_qualifier_descriptor*)response_data;
+					qual->bLength = sizeof(*qual);
+					qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
+					qual->bcdUSB = index->dev->bcdUSB;
+					qual->bDeviceClass = index->dev->bDeviceClass;
+					qual->bDeviceSubClass = index->dev->bDeviceSubClass;
+					qual->bDeviceProtocol = index->dev->bDeviceProtocol;
+					qual->bMaxPacketSize0 = index->dev->bMaxPacketSize0;
+					qual->bNumConfigurations = index->dev->bNumConfigurations;
+					qual->bRESERVED = 0;
+					*response_length = sizeof(*qual);
+					return true;
+				}
+				*response_data = descs->qual;
+				*response_length = descs->qual_len;
+				return true;
+			default:
+				break;
+			}
+			break;
+		default:
+			break;
+		}
+		break;
+	default:
+		break;
+	}
+
+	debug("lookup_connect_response_in: unknown request");
+	return false;
+}
+
+typedef bool (*lookup_connect_out_response_t)(int fd, const struct vusb_connect_descriptors* descs,
+					      const struct usb_ctrlrequest* ctrl, bool* done);
+
+#if SYZ_EXECUTOR || __NR_syz_usb_connect
+static bool lookup_connect_response_out_generic(int fd, const struct vusb_connect_descriptors* descs,
+						const struct usb_ctrlrequest* ctrl, bool* done)
+{
+	switch (ctrl->bRequestType & USB_TYPE_MASK) {
+	case USB_TYPE_STANDARD:
+		switch (ctrl->bRequest) {
+		case USB_REQ_SET_CONFIGURATION:
+			*done = true;
+			return true;
+		default:
+			break;
+		}
+		break;
+	}
+
+	debug("lookup_connect_response_out: unknown request");
+	return false;
+}
+#endif
+
+#if GOOS_linux && (SYZ_EXECUTOR || __NR_syz_usb_connect_ath9k)
+#define ATH9K_FIRMWARE_DOWNLOAD 0x30
+#define ATH9K_FIRMWARE_DOWNLOAD_COMP 0x31
+
+static bool lookup_connect_response_out_ath9k(int fd, const struct vusb_connect_descriptors* descs,
+					      const struct usb_ctrlrequest* ctrl, bool* done)
+{
+	switch (ctrl->bRequestType & USB_TYPE_MASK) {
+	case USB_TYPE_STANDARD:
+		switch (ctrl->bRequest) {
+		case USB_REQ_SET_CONFIGURATION:
+			return true;
+		default:
+			break;
+		}
+		break;
+	case USB_TYPE_VENDOR:
+		switch (ctrl->bRequest) {
+		case ATH9K_FIRMWARE_DOWNLOAD:
+			return true;
+		case ATH9K_FIRMWARE_DOWNLOAD_COMP:
+			*done = true;
+			return true;
+		default:
+			break;
+		}
+		break;
+	}
+
+	debug("lookup_connect_response_out_ath9k: unknown request");
+	return false;
+}
+
+#endif
+
+#if GOOS_linux && (SYZ_EXECUTOR || __NR_syz_usb_control_io)
+
+struct vusb_descriptor {
+	uint8 req_type;
+	uint8 desc_type;
+	uint32 len;
+	char data[0];
+} __attribute__((packed));
+
+struct vusb_descriptors {
+	uint32 len;
+	struct vusb_descriptor* generic;
+	struct vusb_descriptor* descs[0];
+} __attribute__((packed));
+
+struct vusb_response {
+	uint8 type;
+	uint8 req;
+	uint32 len;
+	char data[0];
+} __attribute__((packed));
+
+struct vusb_responses {
+	uint32 len;
+	struct vusb_response* generic;
+	struct vusb_response* resps[0];
+} __attribute__((packed));
+
+static bool lookup_control_response(const struct vusb_descriptors* descs, const struct vusb_responses* resps,
+				    struct usb_ctrlrequest* ctrl, char** response_data, uint32* response_length)
+{
+	int descs_num = 0;
+	int resps_num = 0;
+
+	if (descs)
+		descs_num = (descs->len - offsetof(struct vusb_descriptors, descs)) / sizeof(descs->descs[0]);
+	if (resps)
+		resps_num = (resps->len - offsetof(struct vusb_responses, resps)) / sizeof(resps->resps[0]);
+
+	uint8 req = ctrl->bRequest;
+	uint8 req_type = ctrl->bRequestType & USB_TYPE_MASK;
+	uint8 desc_type = ctrl->wValue >> 8;
+
+	if (req == USB_REQ_GET_DESCRIPTOR) {
+		int i;
+
+		for (i = 0; i < descs_num; i++) {
+			struct vusb_descriptor* desc = descs->descs[i];
+			if (!desc)
+				continue;
+			if (desc->req_type == req_type && desc->desc_type == desc_type) {
+				*response_length = desc->len;
+				if (*response_length != 0)
+					*response_data = &desc->data[0];
+				else
+					*response_data = NULL;
+				return true;
+			}
+		}
+
+		if (descs && descs->generic) {
+			*response_data = &descs->generic->data[0];
+			*response_length = descs->generic->len;
+			return true;
+		}
+	} else {
+		int i;
+
+		for (i = 0; i < resps_num; i++) {
+			struct vusb_response* resp = resps->resps[i];
+			if (!resp)
+				continue;
+			if (resp->type == req_type && resp->req == req) {
+				*response_length = resp->len;
+				if (*response_length != 0)
+					*response_data = &resp->data[0];
+				else
+					*response_data = NULL;
+				return true;
+			}
+		}
+
+		if (resps && resps->generic) {
+			*response_data = &resps->generic->data[0];
+			*response_length = resps->generic->len;
+			return true;
+		}
+	}
+
+	return false;
+}
+
+#endif
+
+
+/* -------------------------------------------------------------------------- */
+
+static int vhci_open(void)
+{
+	return open("/dev/vhci", O_RDWR);
+}
+
+static int vhci_setport(int fd, u_int port)
+{
+	struct vhci_ioc_set_port args;
+
+	args.port = port;
+	return ioctl(fd, VHCI_IOC_SET_PORT, &args);
+}
+
+static int vhci_usb_attach(int fd)
+{
+	return ioctl(fd, VHCI_IOC_USB_ATTACH, NULL);
+}
+
+static int vhci_usb_recv(int fd, void* buf, size_t size)
+{
+	uint8_t* ptr = (uint8_t*)buf;
+	ssize_t done;
+
+	while (1) {
+		done = read(fd, ptr, size);
+		if (done < 0)
+			return -1;
+		if ((size_t)done == size)
+			return 0;
+		size -= done;
+		ptr += done;
+	}
+}
+
+static int vhci_usb_send(int fd, void* buf, size_t size)
+{
+	uint8_t* ptr = (uint8_t*)buf;
+	ssize_t done;
+
+	while (1) {
+		done = write(fd, ptr, size);
+		if (done <= 0)
+			return -1;
+		if ((size_t)done == size)
+			return 0;
+		size -= done;
+		ptr += done;
+	}
+}
+
+/* -------------------------------------------------------------------------- */
+
+static volatile long syz_usb_connect_impl(uint64 speed, uint64 dev_len,
+					  const char* dev, const struct vusb_connect_descriptors* descs,
+					  lookup_connect_out_response_t lookup_connect_response_out)
+{
+	struct usb_device_index* index;
+	int portnum, fd, rv;
+	bool done;
+
+	portnum = procid + 1;
+
+	debug("syz_usb_connect: dev: %p\n", dev);
+	if (!dev) {
+		debug("syz_usb_connect: dev is null\n");
+		return -1;
+	}
+	if (portnum != 1) {
+		/* For now, we support only one proc. */
+		debug("syz_usb_connect: not proc1 %d\n", (int)procid);
+		return -1;
+	}
+
+	debug("syz_usb_connect: device data:\n");
+	debug_dump_data(dev, dev_len);
+
+	fd = vhci_open();
+	if (fd < 0) {
+		debug("syz_usb_connect: vhci_open failed with %d\n", fd);
+		return -1;
+	}
+	debug("syz_usb_connect: vhci_open success\n");
+
+	index = add_usb_index(fd, dev, dev_len);
+	if (!index) {
+		debug("syz_usb_connect: add_usb_index failed\n");
+		goto err;
+	}
+	debug("syz_usb_connect: add_usb_index success\n");
+
+#if USB_DEBUG
+	NONFAILING(analyze_usb_device(index));
+#endif
+
+	rv = vhci_setport(fd, portnum);
+	if (rv != 0) {
+		debug("syz_usb_connect: vhci_setport failed with %d\n", rv);
+		goto err;
+	}
+	debug("syz_usb_connect: vhci_setport success\n");
+
+	rv = vhci_usb_attach(fd);
+	if (rv != 0) {
+		debug("syz_usb_connect: vhci_usb_attach failed with %d\n", rv);
+		goto err;
+	}
+	debug("syz_usb_connect: vhci_usb_attach success\n");
+
+	done = false;
+	while (!done) {
+		vhci_request_t req;
+
+		rv = vhci_usb_recv(fd, &req, sizeof(req));
+		if (rv != 0) {
+			debug("syz_usb_connect: vhci_usb_recv failed with %d\n", errno);
+			goto err;
+		}
+		if (req.type != VHCI_REQ_CTRL) {
+			debug("syz_usb_connect: received non-control transfer\n");
+			goto err;
+		}
+
+		debug("syz_usb_connect: bReqType: 0x%x (%s), bReq: 0x%x, wVal: 0x%x, wIdx: 0x%x, wLen: %d\n",
+		      req.u.ctrl.bmRequestType, (req.u.ctrl.bmRequestType & UE_DIR_IN) ? "IN" : "OUT",
+		      req.u.ctrl.bRequest, UGETW(req.u.ctrl.wValue), UGETW(req.u.ctrl.wIndex), UGETW(req.u.ctrl.wLength));
+
+#if USB_DEBUG
+		analyze_control_request(fd, &req.u.ctrl);
+#endif
+
+		char* response_data = NULL;
+		uint32 response_length = 0;
+		char data[4096];
+
+		if (req.u.ctrl.bmRequestType & UE_DIR_IN) {
+			bool response_found = false;
+			NONFAILING(response_found = lookup_connect_response_in(fd, descs, (const usb_ctrlrequest*)&req.u.ctrl, &response_data, &response_length));
+			if (!response_found) {
+				debug("syz_usb_connect: unknown control IN request\n");
+				goto err;
+			}
+		} else {
+			if (!lookup_connect_response_out(fd, descs, (const usb_ctrlrequest*)&req.u.ctrl, &done)) {
+				debug("syz_usb_connect: unknown control OUT request\n");
+				goto err;
+			}
+			response_data = NULL;
+			response_length = UGETW(req.u.ctrl.wLength);
+		}
+
+		if ((req.u.ctrl.bmRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD &&
+		    req.u.ctrl.bRequest == USB_REQ_SET_CONFIGURATION) {
+			/* TODO: possibly revisit */
+		}
+
+		if (response_length > sizeof(data))
+			response_length = 0;
+		if ((uint32_t)UGETW(req.u.ctrl.wLength) < response_length)
+			response_length = UGETW(req.u.ctrl.wLength);
+
+		if (response_data)
+			memcpy(data, response_data, response_length);
+		else
+			memset(data, 0, response_length);
+
+		if (req.u.ctrl.bmRequestType & UE_DIR_IN) {
+			debug("syz_usb_connect: writing %d bytes\n", response_length);
+			if (response_length > 0) {
+				vhci_response_t res;
+				res.size = response_length;
+				rv = vhci_usb_send(fd, &res, sizeof(res));
+				if (rv == 0)
+					rv = vhci_usb_send(fd, data, response_length);
+			}
+		} else {
+			rv = vhci_usb_recv(fd, data, response_length);
+			debug("syz_usb_connect: read %d bytes\n", response_length);
+			debug_dump_data(&data[0], response_length);
+		}
+		if (rv < 0) {
+			debug("syz_usb_connect: usb_raw_ep0_read/write failed with %d\n", rv);
+			goto err;
+		}
+	}
+
+	sleep_ms(200);
+	debug("syz_usb_connect: configured\n");
+	return fd;
+
+err:
+	close(fd);
+	return -1;
+}
+
+#if SYZ_EXECUTOR || __NR_syz_usb_connect
+static volatile long syz_usb_connect(volatile long a0, volatile long a1,
+				     volatile long a2, volatile long a3)
+{
+	uint64 speed = a0;
+	uint64 dev_len = a1;
+	const char* dev = (const char*)a2;
+	const struct vusb_connect_descriptors* descs = (const struct vusb_connect_descriptors*)a3;
+
+	return syz_usb_connect_impl(speed, dev_len, dev, descs,
+				    &lookup_connect_response_out_generic);
+}
+#endif
+
+#if SYZ_EXECUTOR || __NR_syz_usb_disconnect
+static volatile long syz_usb_disconnect(volatile long a0)
+{
+	int fd = a0;
+
+	int rv = close(fd);
+
+	sleep_ms(200);
+
+	return rv;
+}
+#endif
+
+static void setup_usb(void)
+{
+	if (chmod("/dev/vhci", 0666))
+		fail("failed to chmod /dev/vhci");
+}
+#endif
+#endif
+
 #if GOOS_openbsd
 
 #define __syscall syscall
@@ -3073,7 +4232,7 @@ static bool lookup_connect_response_out_generic(int fd, const struct vusb_connec
 }
 #endif
 
-#if SYZ_EXECUTOR || __NR_syz_usb_connect_ath9k
+#if GOOS_linux && (SYZ_EXECUTOR || __NR_syz_usb_connect_ath9k)
 #define ATH9K_FIRMWARE_DOWNLOAD 0x30
 #define ATH9K_FIRMWARE_DOWNLOAD_COMP 0x31
 
@@ -3108,7 +4267,7 @@ static bool lookup_connect_response_out_ath9k(int fd, const struct vusb_connect_
 
 #endif
 
-#if SYZ_EXECUTOR || __NR_syz_usb_control_io
+#if GOOS_linux && (SYZ_EXECUTOR || __NR_syz_usb_control_io)
 
 struct vusb_descriptor {
 	uint8 req_type;
@@ -3202,7 +4361,6 @@ static bool lookup_control_response(const struct vusb_descriptors* descs, const
 
 #endif
 
-#if GOOS_linux
 
 #define UDC_NAME_LENGTH_MAX 128
 
@@ -3797,10 +4955,6 @@ static volatile long syz_usb_disconnect(volatile long a0)
 }
 #endif
 
-#else
-#error "unknown OS"
-#endif
-
 #endif
 
 #if SYZ_EXECUTOR || __NR_syz_open_dev
diff --git a/pkg/host/host_netbsd.go b/pkg/host/host_netbsd.go
index 8a8e08de9..4d876f90c 100644
--- a/pkg/host/host_netbsd.go
+++ b/pkg/host/host_netbsd.go
@@ -4,14 +4,29 @@
 package host
 
 import (
+	"github.com/google/syzkaller/pkg/osutil"
 	"github.com/google/syzkaller/prog"
 )
 
 func isSupported(c *prog.Syscall, target *prog.Target, sandbox string) (bool, string) {
-	return true, ""
+	switch c.CallName {
+	case "syz_usb_connect", "syz_usb_disconnect":
+		reason := checkUSBEmulation()
+		return reason == "", reason
+	default:
+		return true, ""
+	}
 }
 
 func init() {
 	checkFeature[FeatureCoverage] = unconditionallyEnabled
 	checkFeature[FeatureComparisons] = unconditionallyEnabled
+	checkFeature[FeatureUSBEmulation] = checkUSBEmulation
+}
+
+func checkUSBEmulation() string {
+	if err := osutil.IsAccessible("/dev/vhci"); err != nil {
+		return err.Error()
+	}
+	return ""
 }
diff --git a/sys/netbsd/vusb.txt b/sys/netbsd/vusb.txt
new file mode 100644
index 000000000..866b8ceeb
--- /dev/null
+++ b/sys/netbsd/vusb.txt
@@ -0,0 +1,11 @@
+# Copyright 2020 syzkaller project authors. All rights reserved.
+# Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+# This is a special fd for USB fuzzing and should only be used with syz_usb_* pseudo-syscalls.
+# We don't inherit it from the fd resource, to discourage syzkaller calling raw ioctls on it.
+resource fd_usb[int32]: -1
+
+# These are generic pseudo-syscalls for emulating arbitrary USB devices.
+# They are mostly targeted to cover the enumeration process.
+syz_usb_connect(speed intptr, dev_len len[dev], dev buffer[in], conn_descs buffer[in]) fd_usb (timeout[3000], prog_timeout[3000])
+syz_usb_disconnect(fd fd_usb) (timeout[300])