android_system_core/fastboot/device/usb_client.cpp
David Anderson 4e058cac0d fastboot: Allow fastboot to asynchronously differentiate between fastboot and fastbootd.
It's not possible to programmatically determine which fastboot mode a
device is in, without sending a getvar:is-userspace query. Unfortunately
this is not possible asynchronously, and may interrupt other queries
being processed.

This patch changes fastbootd's USB interface name to "fastbootd". Note
that tools use the protocol number/class and not this string, so it
should be safe to extend. When using "fastboot devices", the interface
name is now listed if set. Note that currently only the Linux version of
the fastboot tool is capable of reading the interface name.

Bug: 156966319
Test: fastboot devices on Linux
Change-Id: I57ccf2bec1dda573fe3ac628a646624b76f45905
2020-05-28 17:42:00 +00:00

303 lines
10 KiB
C++

/*
* Copyright (C) 2018 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "usb_client.h"
#include <endian.h>
#include <fcntl.h>
#include <linux/usb/ch9.h>
#include <linux/usb/functionfs.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <android-base/logging.h>
#include <android-base/properties.h>
constexpr int kMaxPacketSizeFs = 64;
constexpr int kMaxPacketSizeHs = 512;
constexpr int kMaxPacketsizeSs = 1024;
constexpr size_t kFbFfsNumBufs = 16;
constexpr size_t kFbFfsBufSize = 16384;
constexpr const char* kUsbFfsFastbootEp0 = "/dev/usb-ffs/fastboot/ep0";
constexpr const char* kUsbFfsFastbootOut = "/dev/usb-ffs/fastboot/ep1";
constexpr const char* kUsbFfsFastbootIn = "/dev/usb-ffs/fastboot/ep2";
struct FuncDesc {
struct usb_interface_descriptor intf;
struct usb_endpoint_descriptor_no_audio source;
struct usb_endpoint_descriptor_no_audio sink;
} __attribute__((packed));
struct SsFuncDesc {
struct usb_interface_descriptor intf;
struct usb_endpoint_descriptor_no_audio source;
struct usb_ss_ep_comp_descriptor source_comp;
struct usb_endpoint_descriptor_no_audio sink;
struct usb_ss_ep_comp_descriptor sink_comp;
} __attribute__((packed));
struct DescV2 {
struct usb_functionfs_descs_head_v2 header;
// The rest of the structure depends on the flags in the header.
__le32 fs_count;
__le32 hs_count;
__le32 ss_count;
struct FuncDesc fs_descs, hs_descs;
struct SsFuncDesc ss_descs;
} __attribute__((packed));
struct usb_interface_descriptor fastboot_interface = {
.bLength = USB_DT_INTERFACE_SIZE,
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = 0,
.bNumEndpoints = 2,
.bInterfaceClass = USB_CLASS_VENDOR_SPEC,
.bInterfaceSubClass = 66,
.bInterfaceProtocol = 3,
.iInterface = 1, /* first string from the provided table */
};
static struct FuncDesc fs_descriptors = {
.intf = fastboot_interface,
.source =
{
.bLength = sizeof(fs_descriptors.source),
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 1 | USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = kMaxPacketSizeFs,
},
.sink =
{
.bLength = sizeof(fs_descriptors.sink),
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 1 | USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = kMaxPacketSizeFs,
},
};
static struct FuncDesc hs_descriptors = {
.intf = fastboot_interface,
.source =
{
.bLength = sizeof(hs_descriptors.source),
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 1 | USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = kMaxPacketSizeHs,
},
.sink =
{
.bLength = sizeof(hs_descriptors.sink),
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 1 | USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = kMaxPacketSizeHs,
},
};
static struct SsFuncDesc ss_descriptors = {
.intf = fastboot_interface,
.source =
{
.bLength = sizeof(ss_descriptors.source),
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 1 | USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = kMaxPacketsizeSs,
},
.source_comp =
{
.bLength = sizeof(ss_descriptors.source_comp),
.bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
.bMaxBurst = 15,
},
.sink =
{
.bLength = sizeof(ss_descriptors.sink),
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 1 | USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = kMaxPacketsizeSs,
},
.sink_comp =
{
.bLength = sizeof(ss_descriptors.sink_comp),
.bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
.bMaxBurst = 15,
},
};
#define STR_INTERFACE_ "fastbootd"
static const struct {
struct usb_functionfs_strings_head header;
struct {
__le16 code;
const char str1[sizeof(STR_INTERFACE_)];
} __attribute__((packed)) lang0;
} __attribute__((packed)) strings = {
.header =
{
.magic = htole32(FUNCTIONFS_STRINGS_MAGIC),
.length = htole32(sizeof(strings)),
.str_count = htole32(1),
.lang_count = htole32(1),
},
.lang0 =
{
htole16(0x0409), /* en-us */
STR_INTERFACE_,
},
};
static struct DescV2 v2_descriptor = {
.header =
{
.magic = htole32(FUNCTIONFS_DESCRIPTORS_MAGIC_V2),
.length = htole32(sizeof(v2_descriptor)),
.flags = FUNCTIONFS_HAS_FS_DESC | FUNCTIONFS_HAS_HS_DESC |
FUNCTIONFS_HAS_SS_DESC,
},
.fs_count = 3,
.hs_count = 3,
.ss_count = 5,
.fs_descs = fs_descriptors,
.hs_descs = hs_descriptors,
.ss_descs = ss_descriptors,
};
// Reimplementing since usb_ffs_close() does not close the control FD.
static void CloseFunctionFs(usb_handle* h) {
h->bulk_in.reset();
h->bulk_out.reset();
h->control.reset();
}
static bool InitFunctionFs(usb_handle* h) {
LOG(INFO) << "initializing functionfs";
if (h->control < 0) { // might have already done this before
LOG(INFO) << "opening control endpoint " << kUsbFfsFastbootEp0;
h->control.reset(open(kUsbFfsFastbootEp0, O_RDWR));
if (h->control < 0) {
PLOG(ERROR) << "cannot open control endpoint " << kUsbFfsFastbootEp0;
goto err;
}
auto ret = write(h->control.get(), &v2_descriptor, sizeof(v2_descriptor));
if (ret < 0) {
PLOG(ERROR) << "cannot write descriptors " << kUsbFfsFastbootEp0;
goto err;
}
ret = write(h->control.get(), &strings, sizeof(strings));
if (ret < 0) {
PLOG(ERROR) << "cannot write strings " << kUsbFfsFastbootEp0;
goto err;
}
// Signal only when writing the descriptors to ffs
android::base::SetProperty("sys.usb.ffs.ready", "1");
}
h->bulk_out.reset(open(kUsbFfsFastbootOut, O_RDONLY));
if (h->bulk_out < 0) {
PLOG(ERROR) << "cannot open bulk-out endpoint " << kUsbFfsFastbootOut;
goto err;
}
h->bulk_in.reset(open(kUsbFfsFastbootIn, O_WRONLY));
if (h->bulk_in < 0) {
PLOG(ERROR) << "cannot open bulk-in endpoint " << kUsbFfsFastbootIn;
goto err;
}
h->read_aiob.fd = h->bulk_out.get();
h->write_aiob.fd = h->bulk_in.get();
h->reads_zero_packets = false;
return true;
err:
CloseFunctionFs(h);
return false;
}
ClientUsbTransport::ClientUsbTransport()
: handle_(std::unique_ptr<usb_handle>(create_usb_handle(kFbFfsNumBufs, kFbFfsBufSize))) {
if (!InitFunctionFs(handle_.get())) {
handle_.reset(nullptr);
}
}
ssize_t ClientUsbTransport::Read(void* data, size_t len) {
if (handle_ == nullptr || len > SSIZE_MAX) {
return -1;
}
char* char_data = static_cast<char*>(data);
size_t bytes_read_total = 0;
while (bytes_read_total < len) {
auto bytes_to_read = std::min(len - bytes_read_total, kFbFfsNumBufs * kFbFfsBufSize);
auto bytes_read_now =
handle_->read(handle_.get(), char_data, bytes_to_read, true /* allow_partial */);
if (bytes_read_now < 0) {
return bytes_read_total == 0 ? -1 : bytes_read_total;
}
bytes_read_total += bytes_read_now;
char_data += bytes_read_now;
if (static_cast<size_t>(bytes_read_now) < bytes_to_read) {
break;
}
}
return bytes_read_total;
}
ssize_t ClientUsbTransport::Write(const void* data, size_t len) {
if (handle_ == nullptr || len > SSIZE_MAX) {
return -1;
}
const char* char_data = reinterpret_cast<const char*>(data);
size_t bytes_written_total = 0;
while (bytes_written_total < len) {
auto bytes_to_write = std::min(len - bytes_written_total, kFbFfsNumBufs * kFbFfsBufSize);
auto bytes_written_now = handle_->write(handle_.get(), data, bytes_to_write);
if (bytes_written_now < 0) {
return bytes_written_total == 0 ? -1 : bytes_written_total;
}
bytes_written_total += bytes_written_now;
char_data += bytes_written_now;
if (static_cast<size_t>(bytes_written_now) < bytes_to_write) {
break;
}
}
return bytes_written_total;
}
int ClientUsbTransport::Close() {
if (handle_ == nullptr) {
return -1;
}
CloseFunctionFs(handle_.get());
return 0;
}
int ClientUsbTransport::Reset() {
return 0;
}