1 files changed, 259 insertions, 0 deletions
diff --git a/host/frontend/gcastv2/webrtc/AdbWebSocketHandler.cpp b/host/frontend/gcastv2/webrtc/AdbWebSocketHandler.cpp
new file mode 100644
index 000000000..dcb6d503d
--- /dev/null
+++ b/host/frontend/gcastv2/webrtc/AdbWebSocketHandler.cpp
@@ -0,0 +1,259 @@
+/*
+ * Copyright (C) 2019 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 <webrtc/AdbWebSocketHandler.h>
+
+#include "Utils.h"
+
+#include <https/BaseConnection.h>
+#include <https/Support.h>
+
+#include <android-base/logging.h>
+
+#include <unistd.h>
+
+using namespace android;
+
+struct AdbWebSocketHandler::AdbConnection : public BaseConnection {
+    explicit AdbConnection(
+            AdbWebSocketHandler *parent,
+            std::shared_ptr<RunLoop> runLoop,
+            int sock);
+
+    void send(const void *_data, size_t size);
+
+protected:
+    ssize_t processClientRequest(const void *data, size_t size) override;
+    void onDisconnect(int err) override;
+
+private:
+    AdbWebSocketHandler *mParent;
+};
+
+////////////////////////////////////////////////////////////////////////////////
+
+AdbWebSocketHandler::AdbConnection::AdbConnection(
+        AdbWebSocketHandler *parent,
+        std::shared_ptr<RunLoop> runLoop,
+        int sock)
+    : BaseConnection(runLoop, sock),
+      mParent(parent) {
+}
+
+// Thanks for calling it a crc32, adb documentation!
+static uint32_t computeNotACrc32(const void *_data, size_t size) {
+    auto data = static_cast<const uint8_t *>(_data);
+    uint32_t sum = 0;
+    for (size_t i = 0; i < size; ++i) {
+        sum += data[i];
+    }
+
+    return sum;
+}
+
+static int verifyAdbHeader(
+        const void *_data, size_t size, size_t *_payloadLength) {
+    auto data = static_cast<const uint8_t *>(_data);
+
+    *_payloadLength = 0;
+
+    if (size < 24) {
+        return -EAGAIN;
+    }
+
+    uint32_t command = U32LE_AT(data);
+    uint32_t magic = U32LE_AT(data + 20);
+
+    if (command != (magic ^ 0xffffffff)) {
+        return -EINVAL;
+    }
+
+    uint32_t payloadLength = U32LE_AT(data + 12);
+
+    if (size < 24 + payloadLength) {
+        return -EAGAIN;
+    }
+
+    auto payloadCrc = U32LE_AT(data + 16);
+    auto crc32 = computeNotACrc32(data + 24, payloadLength);
+
+    if (payloadCrc != crc32) {
+        return -EINVAL;
+    }
+
+    *_payloadLength = payloadLength;
+
+    return 0;
+}
+
+ssize_t AdbWebSocketHandler::AdbConnection::processClientRequest(
+        const void *_data, size_t size) {
+    auto data = static_cast<const uint8_t *>(_data);
+
+    LOG(VERBOSE)
+        << "AdbConnection::processClientRequest (size = " << size << ")";
+
+    // hexdump(data, size);
+
+    size_t payloadLength;
+    int err = verifyAdbHeader(data, size, &payloadLength);
+
+    if (err) {
+        return err;
+    }
+
+    mParent->sendMessage(
+            data, payloadLength + 24, WebSocketHandler::SendMode::binary);
+
+    return payloadLength + 24;
+}
+
+void AdbWebSocketHandler::AdbConnection::onDisconnect(int err) {
+    LOG(INFO) << "AdbConnection::onDisconnect(err=" << err << ")";
+
+    mParent->sendMessage(
+            nullptr /* data */,
+            0 /* size */,
+            WebSocketHandler::SendMode::closeConnection);
+}
+
+void AdbWebSocketHandler::AdbConnection::send(const void *_data, size_t size) {
+    BaseConnection::send(_data, size);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+AdbWebSocketHandler::AdbWebSocketHandler(
+        std::shared_ptr<RunLoop> runLoop,
+        const std::string &adb_host_and_port)
+    : mRunLoop(runLoop),
+      mSocket(-1) {
+    LOG(INFO) << "Connecting to " << adb_host_and_port;
+
+    auto err = setupSocket(adb_host_and_port);
+    CHECK(!err);
+
+    mAdbConnection = std::make_shared<AdbConnection>(this, mRunLoop, mSocket);
+}
+
+AdbWebSocketHandler::~AdbWebSocketHandler() {
+    if (mSocket >= 0) {
+        close(mSocket);
+        mSocket = -1;
+    }
+}
+
+void AdbWebSocketHandler::run() {
+    mAdbConnection->run();
+}
+
+int AdbWebSocketHandler::setupSocket(const std::string &adb_host_and_port) {
+    auto colonPos = adb_host_and_port.find(':');
+    if (colonPos == std::string::npos) {
+        return -EINVAL;
+    }
+
+    auto host = adb_host_and_port.substr(0, colonPos);
+
+    const char *portString = adb_host_and_port.c_str() + colonPos + 1;
+    char *end;
+    unsigned long port = strtoul(portString, &end, 10);
+
+    if (end == portString || *end != '\0' || port > 65535) {
+        return -EINVAL;
+    }
+
+    int err;
+
+    int sock = socket(PF_INET, SOCK_STREAM, 0);
+
+    if (sock < 0) {
+        err = -errno;
+        goto bail;
+    }
+
+    makeFdNonblocking(sock);
+
+    sockaddr_in addr;
+    memset(addr.sin_zero, 0, sizeof(addr.sin_zero));
+    addr.sin_family = AF_INET;
+    addr.sin_addr.s_addr = inet_addr(host.c_str());
+    addr.sin_port = htons(port);
+
+    if (connect(sock,
+                reinterpret_cast<const sockaddr *>(&addr),
+                sizeof(addr)) < 0
+            && errno != EINPROGRESS) {
+        err = -errno;
+        goto bail2;
+    }
+
+    mSocket = sock;
+
+    return 0;
+
+bail2:
+    close(sock);
+    sock = -1;
+
+bail:
+    return err;
+}
+
+int AdbWebSocketHandler::handleMessage(
+        uint8_t headerByte, const uint8_t *msg, size_t len) {
+    LOG(VERBOSE)
+        << "headerByte = "
+        << StringPrintf("0x%02x", (unsigned)headerByte);
+
+    // hexdump(msg, len);
+
+    if (!(headerByte & 0x80)) {
+        // I only want to receive whole messages here, not fragments.
+        return -EINVAL;
+    }
+
+    auto opcode = headerByte & 0x1f;
+    switch (opcode) {
+        case 0x8:
+        {
+            // closeConnection.
+            break;
+        }
+
+        case 0x2:
+        {
+            // binary
+
+            size_t payloadLength;
+            int err = verifyAdbHeader(msg, len, &payloadLength);
+
+            if (err || len != 24 + payloadLength) {
+                LOG(ERROR) << "websocket message is not a valid adb message.";
+                return -EINVAL;
+            }
+
+            mAdbConnection->send(msg, len);
+            break;
+        }
+
+        default:
+            return -EINVAL;
+    }
+
+    return 0;
+}
+