From 71fb82a271cc793f5c21f492f5f08507ba49e376 Mon Sep 17 00:00:00 2001
From: Hridya Valsaraju <hridya@google.com>
Date: Thu, 2 Aug 2018 15:02:06 -0700
Subject: [PATCH] Add sideload, fastboot as reboot targets in init

Rebooting to these targets requires writing bootloader
messages and thus root. Moving them into init means that
adb, reboot don't need root to use these targets.

Test: try rebooting to these targets
Bug: 78793464
Change-Id: Ia002d1e3b1cb0c0616f60435fb9af4dce162cf84
---
 adb/daemon/services.cpp | 65 ++++++++++++++++++++++-------------------
 init/reboot.cpp         | 14 +++++++++
 2 files changed, 49 insertions(+), 30 deletions(-)

diff --git a/adb/daemon/services.cpp b/adb/daemon/services.cpp
index dfcc52d95..841769043 100644
--- a/adb/daemon/services.cpp
+++ b/adb/daemon/services.cpp
@@ -26,6 +26,8 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/un.h>
 #include <unistd.h>
 
 #include <thread>
@@ -96,41 +98,44 @@ void restart_usb_service(unique_fd fd) {
 
 void reboot_service(unique_fd fd, const std::string& arg) {
     std::string reboot_arg = arg;
-    bool auto_reboot = false;
-
-    if (reboot_arg == "sideload-auto-reboot") {
-        auto_reboot = true;
-        reboot_arg = "sideload";
-    }
-
-    // It reboots into sideload mode by setting "--sideload" or "--sideload_auto_reboot"
-    // in the command file.
-    if (reboot_arg == "sideload") {
-        if (getuid() != 0) {
-            WriteFdExactly(fd.get(), "'adb root' is required for 'adb reboot sideload'.\n");
-            return;
-        }
-
-        const std::vector<std::string> options = {auto_reboot ? "--sideload_auto_reboot"
-                                                              : "--sideload"};
-        std::string err;
-        if (!write_bootloader_message(options, &err)) {
-            D("Failed to set bootloader message: %s", err.c_str());
-            return;
-        }
-
-        reboot_arg = "recovery";
-    }
-
     sync();
 
     if (reboot_arg.empty()) reboot_arg = "adb";
     std::string reboot_string = android::base::StringPrintf("reboot,%s", reboot_arg.c_str());
-    if (!android::base::SetProperty(ANDROID_RB_PROPERTY, reboot_string)) {
-        WriteFdFmt(fd.get(), "reboot (%s) failed\n", reboot_string.c_str());
-        return;
-    }
 
+    if (reboot_arg == "fastboot" && access("/dev/socket/recovery", F_OK) == 0) {
+        LOG(INFO) << "Recovery specific reboot fastboot";
+        /*
+         * The socket is created to allow switching between recovery and
+         * fastboot.
+         */
+        android::base::unique_fd sock(socket(AF_UNIX, SOCK_STREAM, 0));
+        if (sock < 0) {
+            WriteFdFmt(fd, "reboot (%s) create\n", strerror(errno));
+            PLOG(ERROR) << "Creating recovery socket failed";
+            return;
+        }
+
+        sockaddr_un addr = {.sun_family = AF_UNIX};
+        strncpy(addr.sun_path, "/dev/socket/recovery", sizeof(addr.sun_path) - 1);
+        if (connect(sock, reinterpret_cast<sockaddr*>(&addr), sizeof(addr)) == -1) {
+            WriteFdFmt(fd, "reboot (%s) connect\n", strerror(errno));
+            PLOG(ERROR) << "Couldn't connect to recovery socket";
+            return;
+        }
+        const char msg_switch_to_fastboot = 'f';
+        auto ret = adb_write(sock, &msg_switch_to_fastboot, sizeof(msg_switch_to_fastboot));
+        if (ret != sizeof(msg_switch_to_fastboot)) {
+            WriteFdFmt(fd, "reboot (%s) write\n", strerror(errno));
+            PLOG(ERROR) << "Couldn't write message to recovery socket to switch to fastboot";
+            return;
+        }
+    } else {
+        if (!android::base::SetProperty(ANDROID_RB_PROPERTY, reboot_string)) {
+            WriteFdFmt(fd.get(), "reboot (%s) failed\n", reboot_string.c_str());
+            return;
+        }
+    }
     // Don't return early. Give the reboot command time to take effect
     // to avoid messing up scripts which do "adb reboot && adb wait-for-device"
     while (true) {
diff --git a/init/reboot.cpp b/init/reboot.cpp
index 11507f489..cd3879fc0 100644
--- a/init/reboot.cpp
+++ b/init/reboot.cpp
@@ -516,7 +516,21 @@ bool HandlePowerctlMessage(const std::string& command) {
                                   "bootloader_message: "
                                << err;
                 }
+            } else if (reboot_target == "sideload" || reboot_target == "sideload-auto-reboot" ||
+                       reboot_target == "fastboot") {
+                std::string arg = reboot_target == "sideload-auto-reboot" ? "sideload_auto_reboot"
+                                                                          : reboot_target;
+                const std::vector<std::string> options = {
+                        "--" + arg,
+                };
+                std::string err;
+                if (!write_bootloader_message(options, &err)) {
+                    LOG(ERROR) << "Failed to set bootloader message: " << err;
+                    return false;
+                }
+                reboot_target = "recovery";
             }
+
             // If there is an additional parameter, pass it along
             if ((cmd_params.size() == 3) && cmd_params[2].size()) {
                 reboot_target += "," + cmd_params[2];