| // Copyright 2019 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. |
| |
| // Implementation of syz_usb_* pseudo-syscalls. |
| |
| #define USB_DEBUG 0 |
| |
| #define USB_MAX_EP_NUM 32 |
| |
| struct usb_device_index { |
| struct usb_device_descriptor* dev; |
| struct usb_config_descriptor* config; |
| unsigned config_length; |
| struct usb_interface_descriptor* iface; |
| struct usb_endpoint_descriptor* eps[USB_MAX_EP_NUM]; |
| unsigned eps_num; |
| }; |
| |
| static bool parse_usb_descriptor(char* buffer, size_t length, struct usb_device_index* index) |
| { |
| if (length < sizeof(*index->dev) + sizeof(*index->config) + sizeof(*index->iface)) |
| return false; |
| |
| index->dev = (struct usb_device_descriptor*)buffer; |
| index->config = (struct usb_config_descriptor*)(buffer + sizeof(*index->dev)); |
| index->config_length = length - sizeof(*index->dev); |
| index->iface = (struct usb_interface_descriptor*)(buffer + sizeof(*index->dev) + sizeof(*index->config)); |
| |
| index->eps_num = 0; |
| 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_ENDPOINT) { |
| index->eps[index->eps_num] = (struct usb_endpoint_descriptor*)(buffer + offset); |
| index->eps_num++; |
| } |
| if (index->eps_num == USB_MAX_EP_NUM) |
| break; |
| offset += desc_length; |
| } |
| |
| return true; |
| } |
| |
| enum usb_fuzzer_event_type { |
| USB_FUZZER_EVENT_INVALID, |
| USB_FUZZER_EVENT_CONNECT, |
| USB_FUZZER_EVENT_DISCONNECT, |
| USB_FUZZER_EVENT_SUSPEND, |
| USB_FUZZER_EVENT_RESUME, |
| USB_FUZZER_EVENT_CONTROL, |
| }; |
| |
| struct usb_fuzzer_event { |
| uint32 type; |
| uint32 length; |
| char data[0]; |
| }; |
| |
| struct usb_fuzzer_init { |
| uint64 speed; |
| const char* driver_name; |
| const char* device_name; |
| }; |
| |
| struct usb_fuzzer_ep_io { |
| uint16 ep; |
| uint16 flags; |
| uint32 length; |
| char data[0]; |
| }; |
| |
| #define USB_FUZZER_IOCTL_INIT _IOW('U', 0, struct usb_fuzzer_init) |
| #define USB_FUZZER_IOCTL_RUN _IO('U', 1) |
| #define USB_FUZZER_IOCTL_EVENT_FETCH _IOR('U', 2, struct usb_fuzzer_event) |
| #define USB_FUZZER_IOCTL_EP0_WRITE _IOW('U', 3, struct usb_fuzzer_ep_io) |
| #define USB_FUZZER_IOCTL_EP0_READ _IOWR('U', 4, struct usb_fuzzer_ep_io) |
| #define USB_FUZZER_IOCTL_EP_ENABLE _IOW('U', 5, struct usb_endpoint_descriptor) |
| #define USB_FUZZER_IOCTL_EP_WRITE _IOW('U', 7, struct usb_fuzzer_ep_io) |
| #define USB_FUZZER_IOCTL_EP_READ _IOWR('U', 8, struct usb_fuzzer_ep_io) |
| #define USB_FUZZER_IOCTL_CONFIGURE _IO('U', 9) |
| #define USB_FUZZER_IOCTL_VBUS_DRAW _IOW('U', 10, uint32) |
| |
| int usb_fuzzer_open() |
| { |
| return open("/sys/kernel/debug/usb-fuzzer", O_RDWR); |
| } |
| |
| int usb_fuzzer_init(int fd, uint32 speed, const char* driver, const char* device) |
| { |
| struct usb_fuzzer_init arg; |
| arg.speed = speed; |
| arg.driver_name = driver; |
| arg.device_name = device; |
| return ioctl(fd, USB_FUZZER_IOCTL_INIT, &arg); |
| } |
| |
| int usb_fuzzer_run(int fd) |
| { |
| return ioctl(fd, USB_FUZZER_IOCTL_RUN, 0); |
| } |
| |
| int usb_fuzzer_event_fetch(int fd, struct usb_fuzzer_event* event) |
| { |
| return ioctl(fd, USB_FUZZER_IOCTL_EVENT_FETCH, event); |
| } |
| |
| int usb_fuzzer_ep0_write(int fd, struct usb_fuzzer_ep_io* io) |
| { |
| return ioctl(fd, USB_FUZZER_IOCTL_EP0_WRITE, io); |
| } |
| |
| int usb_fuzzer_ep0_read(int fd, struct usb_fuzzer_ep_io* io) |
| { |
| return ioctl(fd, USB_FUZZER_IOCTL_EP0_READ, io); |
| } |
| |
| int usb_fuzzer_ep_write(int fd, struct usb_fuzzer_ep_io* io) |
| { |
| return ioctl(fd, USB_FUZZER_IOCTL_EP_WRITE, io); |
| } |
| |
| int usb_fuzzer_ep_read(int fd, struct usb_fuzzer_ep_io* io) |
| { |
| return ioctl(fd, USB_FUZZER_IOCTL_EP_READ, io); |
| } |
| |
| int usb_fuzzer_ep_enable(int fd, struct usb_endpoint_descriptor* desc) |
| { |
| return ioctl(fd, USB_FUZZER_IOCTL_EP_ENABLE, desc); |
| } |
| |
| int usb_fuzzer_configure(int fd) |
| { |
| return ioctl(fd, USB_FUZZER_IOCTL_CONFIGURE, 0); |
| } |
| |
| int usb_fuzzer_vbus_draw(int fd, uint32 power) |
| { |
| return ioctl(fd, USB_FUZZER_IOCTL_VBUS_DRAW, power); |
| } |
| |
| #define USB_MAX_PACKET_SIZE 1024 |
| |
| struct usb_fuzzer_control_event { |
| struct usb_fuzzer_event inner; |
| struct usb_ctrlrequest ctrl; |
| char data[USB_MAX_PACKET_SIZE]; |
| }; |
| |
| struct usb_fuzzer_ep_io_data { |
| struct usb_fuzzer_ep_io inner; |
| char data[USB_MAX_PACKET_SIZE]; |
| }; |
| |
| 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 = "syzkaller"; |
| |
| static bool lookup_connect_response(struct vusb_connect_descriptors* descs, struct usb_device_index* index, |
| struct usb_ctrlrequest* ctrl, char** response_data, uint32* response_length) |
| { |
| uint8 str_idx; |
| |
| 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 (str_idx >= descs->strs_len) { |
| // Use the default string if we ran out. |
| *response_data = (char*)default_string; |
| *response_length = strlen(default_string); |
| } else { |
| *response_data = descs->strs[str_idx].str; |
| *response_length = descs->strs[str_idx].len; |
| } |
| return true; |
| case USB_DT_BOS: |
| *response_data = descs->bos; |
| *response_length = descs->bos_len; |
| return true; |
| case USB_DT_DEVICE_QUALIFIER: |
| *response_data = descs->qual; |
| *response_length = descs->qual_len; |
| return true; |
| default: |
| fail("syz_usb_connect: no response"); |
| return false; |
| } |
| break; |
| default: |
| fail("syz_usb_connect: no response"); |
| return false; |
| } |
| break; |
| default: |
| fail("syz_usb_connect: no response"); |
| return false; |
| } |
| |
| return false; |
| } |
| |
| 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; |
| char* dev = (char*)a2; |
| struct vusb_connect_descriptors* descs = (struct vusb_connect_descriptors*)a3; |
| |
| debug("syz_usb_connect: dev: %p\n", dev); |
| if (!dev) { |
| debug("syz_usb_connect: dev is null\n"); |
| return -1; |
| } |
| |
| debug("syz_usb_connect: device data:\n"); |
| debug_dump_data(dev, dev_len); |
| |
| struct usb_device_index index; |
| memset(&index, 0, sizeof(index)); |
| int rv = 0; |
| NONFAILING(rv = parse_usb_descriptor(dev, dev_len, &index)); |
| if (!rv) { |
| debug("syz_usb_connect: parse_usb_descriptor failed with %d\n", rv); |
| return rv; |
| } |
| debug("syz_usb_connect: parsed usb descriptor, %d endpoints found\n", index.eps_num); |
| |
| int fd = usb_fuzzer_open(); |
| if (fd < 0) { |
| debug("syz_usb_connect: usb_fuzzer_open failed with %d\n", rv); |
| return fd; |
| } |
| debug("syz_usb_connect: usb_fuzzer_open success\n"); |
| |
| // TODO: consider creating two dummy_udc's per proc to increace the chance of |
| // triggering interaction between multiple USB devices within the same program. |
| char device[32]; |
| sprintf(&device[0], "dummy_udc.%llu", procid); |
| rv = usb_fuzzer_init(fd, speed, "dummy_udc", &device[0]); |
| if (rv < 0) { |
| debug("syz_usb_connect: usb_fuzzer_init failed with %d\n", rv); |
| return rv; |
| } |
| debug("syz_usb_connect: usb_fuzzer_init success\n"); |
| |
| rv = usb_fuzzer_run(fd); |
| if (rv < 0) { |
| debug("syz_usb_connect: usb_fuzzer_run failed with %d\n", rv); |
| return rv; |
| } |
| debug("syz_usb_connect: usb_fuzzer_run success\n"); |
| |
| bool done = false; |
| while (!done) { |
| struct usb_fuzzer_control_event event; |
| event.inner.type = 0; |
| event.inner.length = sizeof(event.ctrl); |
| rv = usb_fuzzer_event_fetch(fd, (struct usb_fuzzer_event*)&event); |
| if (rv < 0) { |
| debug("syz_usb_connect: usb_fuzzer_event_fetch failed with %d\n", rv); |
| return rv; |
| } |
| if (event.inner.type != USB_FUZZER_EVENT_CONTROL) |
| continue; |
| |
| debug("syz_usb_connect: bRequestType: 0x%x (%s), bRequest: 0x%x, wValue: 0x%x, wIndex: 0x%x, wLength: %d\n", |
| event.ctrl.bRequestType, (event.ctrl.bRequestType & USB_DIR_IN) ? "IN" : "OUT", |
| event.ctrl.bRequest, event.ctrl.wValue, event.ctrl.wIndex, event.ctrl.wLength); |
| |
| bool response_found = false; |
| char* response_data = NULL; |
| uint32 response_length = 0; |
| |
| if (event.ctrl.bRequestType & USB_DIR_IN) { |
| NONFAILING(response_found = lookup_connect_response(descs, &index, &event.ctrl, &response_data, &response_length)); |
| if (!response_found) { |
| debug("syz_usb_connect: unknown control IN request\n"); |
| return -1; |
| } |
| } else { |
| if ((event.ctrl.bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD || |
| event.ctrl.bRequest != USB_REQ_SET_CONFIGURATION) { |
| fail("syz_usb_connect: unknown control OUT request"); |
| return -1; |
| } |
| done = true; |
| } |
| |
| if (done) { |
| rv = usb_fuzzer_vbus_draw(fd, index.config->bMaxPower); |
| if (rv < 0) { |
| debug("syz_usb_connect: usb_fuzzer_vbus_draw failed with %d\n", rv); |
| return rv; |
| } |
| rv = usb_fuzzer_configure(fd); |
| if (rv < 0) { |
| debug("syz_usb_connect: usb_fuzzer_configure failed with %d\n", rv); |
| return rv; |
| } |
| unsigned ep; |
| for (ep = 0; ep < index.eps_num; ep++) { |
| rv = usb_fuzzer_ep_enable(fd, index.eps[ep]); |
| if (rv < 0) { |
| debug("syz_usb_connect: usb_fuzzer_ep_enable failed with %d\n", rv); |
| } else { |
| debug("syz_usb_connect: endpoint %d enabled\n", ep); |
| } |
| } |
| } |
| |
| struct usb_fuzzer_ep_io_data response; |
| response.inner.ep = 0; |
| response.inner.flags = 0; |
| if (response_length > sizeof(response.data)) |
| response_length = 0; |
| if (event.ctrl.wLength < response_length) |
| response_length = event.ctrl.wLength; |
| response.inner.length = response_length; |
| if (response_data) |
| memcpy(&response.data[0], response_data, response_length); |
| else |
| memset(&response.data[0], 0, response_length); |
| |
| debug("syz_usb_connect: reply length = %d\n", response.inner.length); |
| if (event.ctrl.bRequestType & USB_DIR_IN) |
| rv = usb_fuzzer_ep0_write(fd, (struct usb_fuzzer_ep_io*)&response); |
| else |
| rv = usb_fuzzer_ep0_read(fd, (struct usb_fuzzer_ep_io*)&response); |
| if (rv < 0) { |
| debug("syz_usb_connect: usb_fuzzer_ep0_read/write failed with %d\n", rv); |
| return rv; |
| } |
| } |
| |
| sleep_ms(200); |
| |
| debug("syz_usb_connect: configured\n"); |
| |
| return fd; |
| } |
| |
| #if 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(struct vusb_descriptors* descs, struct vusb_responses* resps, |
| struct usb_ctrlrequest* ctrl, char** response_data, uint32* response_length) |
| { |
| int descs_num = (descs->len - offsetof(struct vusb_descriptors, descs)) / sizeof(descs->descs[0]); |
| int 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->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->generic) { |
| *response_data = &resps->generic->data[0]; |
| *response_length = resps->generic->len; |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| #if USB_DEBUG |
| #include <linux/hid.h> |
| #include <linux/usb/cdc.h> |
| #include <linux/usb/ch11.h> |
| #include <linux/usb/ch9.h> |
| |
| static void analyze_control_request(struct usb_ctrlrequest* ctrl) |
| { |
| 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: |
| case USB_DT_CONFIG: |
| case USB_DT_STRING: |
| case HID_DT_REPORT: |
| case USB_DT_BOS: |
| case USB_DT_HUB: |
| case USB_DT_SS_HUB: |
| return; |
| } |
| } |
| break; |
| case USB_TYPE_CLASS: |
| switch (ctrl->bRequest) { |
| case USB_REQ_GET_INTERFACE: |
| case USB_REQ_GET_CONFIGURATION: |
| case USB_REQ_GET_STATUS: |
| case USB_CDC_GET_NTB_PARAMETERS: |
| return; |
| } |
| } |
| fail("analyze_control_request: unknown control request (0x%x, 0x%x, 0x%x)", |
| ctrl->bRequestType, ctrl->bRequest, ctrl->wValue); |
| } |
| #endif |
| |
| static volatile long syz_usb_control_io(volatile long a0, volatile long a1, volatile long a2) |
| { |
| int fd = a0; |
| struct vusb_descriptors* descs = (struct vusb_descriptors*)a1; |
| struct vusb_responses* resps = (struct vusb_responses*)a2; |
| |
| struct usb_fuzzer_control_event event; |
| event.inner.type = 0; |
| event.inner.length = USB_MAX_PACKET_SIZE; |
| int rv = usb_fuzzer_event_fetch(fd, (struct usb_fuzzer_event*)&event); |
| if (rv < 0) { |
| debug("syz_usb_control_io: usb_fuzzer_ep0_read failed with %d\n", rv); |
| return rv; |
| } |
| if (event.inner.type != USB_FUZZER_EVENT_CONTROL) { |
| debug("syz_usb_control_io: wrong event type: %d\n", (int)event.inner.type); |
| return -1; |
| } |
| |
| debug("syz_usb_control_io: bRequestType: 0x%x (%s), bRequest: 0x%x, wValue: 0x%x, wIndex: 0x%x, wLength: %d\n", |
| event.ctrl.bRequestType, (event.ctrl.bRequestType & USB_DIR_IN) ? "IN" : "OUT", |
| event.ctrl.bRequest, event.ctrl.wValue, event.ctrl.wIndex, event.ctrl.wLength); |
| |
| bool response_found = false; |
| char* response_data = NULL; |
| uint32 response_length = 0; |
| |
| if (event.ctrl.bRequestType & USB_DIR_IN) { |
| NONFAILING(response_found = lookup_control_response(descs, resps, &event.ctrl, &response_data, &response_length)); |
| if (!response_found) { |
| #if USB_DEBUG |
| analyze_control_request(&event.ctrl); |
| #endif |
| debug("syz_usb_control_io: unknown control IN request\n"); |
| return -1; |
| } |
| } else { |
| response_length = event.ctrl.wLength; |
| } |
| |
| struct usb_fuzzer_ep_io_data response; |
| response.inner.ep = 0; |
| response.inner.flags = 0; |
| if (response_length > sizeof(response.data)) |
| response_length = 0; |
| if (event.ctrl.wLength < response_length) |
| response_length = event.ctrl.wLength; |
| response.inner.length = response_length; |
| if (response_data) |
| memcpy(&response.data[0], response_data, response_length); |
| else |
| memset(&response.data[0], 0, response_length); |
| |
| if (event.ctrl.bRequestType & USB_DIR_IN) { |
| debug("syz_usb_control_io: IN, length = %d\n", response.inner.length); |
| debug_dump_data(&response.data[0], response.inner.length); |
| rv = usb_fuzzer_ep0_write(fd, (struct usb_fuzzer_ep_io*)&response); |
| } else { |
| rv = usb_fuzzer_ep0_read(fd, (struct usb_fuzzer_ep_io*)&response); |
| debug("syz_usb_control_io: OUT, length = %d\n", response.inner.length); |
| debug_dump_data(&event.data[0], response.inner.length); |
| } |
| if (rv < 0) { |
| debug("syz_usb_control_io: usb_fuzzer_ep0_read/write failed with %d\n", rv); |
| return rv; |
| } |
| |
| sleep_ms(200); |
| |
| return 0; |
| } |
| #endif |
| |
| #if SYZ_EXECUTOR || __NR_syz_usb_ep_write |
| static volatile long syz_usb_ep_write(volatile long a0, volatile long a1, volatile long a2, volatile long a3) |
| { |
| int fd = a0; |
| uint16 ep = a1; |
| uint32 len = a2; |
| char* data = (char*)a3; |
| |
| struct usb_fuzzer_ep_io_data io_data; |
| io_data.inner.ep = ep; |
| io_data.inner.flags = 0; |
| if (len > sizeof(io_data.data)) |
| len = sizeof(io_data.data); |
| io_data.inner.length = len; |
| NONFAILING(memcpy(&io_data.data[0], data, len)); |
| |
| int rv = usb_fuzzer_ep_write(fd, (struct usb_fuzzer_ep_io*)&io_data); |
| if (rv < 0) { |
| debug("syz_usb_ep_write: usb_fuzzer_ep_write failed with %d\n", rv); |
| return rv; |
| } |
| |
| sleep_ms(200); |
| |
| return 0; |
| } |
| #endif |
| |
| #if SYZ_EXECUTOR || __NR_syz_usb_ep_read |
| static volatile long syz_usb_ep_read(volatile long a0, volatile long a1, volatile long a2, volatile long a3) |
| { |
| int fd = a0; |
| uint16 ep = a1; |
| uint32 len = a2; |
| char* data = (char*)a3; |
| |
| struct usb_fuzzer_ep_io_data io_data; |
| io_data.inner.ep = ep; |
| io_data.inner.flags = 0; |
| if (len > sizeof(io_data.data)) |
| len = sizeof(io_data.data); |
| io_data.inner.length = len; |
| |
| int rv = usb_fuzzer_ep_read(fd, (struct usb_fuzzer_ep_io*)&io_data); |
| if (rv < 0) { |
| debug("syz_usb_ep_read: usb_fuzzer_ep_read failed with %d\n", rv); |
| return rv; |
| } |
| |
| NONFAILING(memcpy(&data[0], &io_data.data[0], io_data.inner.length)); |
| |
| debug("syz_usb_ep_read: received data:\n"); |
| debug_dump_data(&io_data.data[0], io_data.inner.length); |
| |
| sleep_ms(200); |
| |
| return 0; |
| } |
| #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 |