From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Danny Lin Date: Wed, 7 Oct 2020 00:24:54 -0700 Subject: [PATCH] init: Set properties to make SafetyNet pass Google's SafetyNet integrity checks will check the values of these properties when performing basic attestation. Setting fake values helps us pass basic SafetyNet with no Magisk Hide or kernel patches necessary. Note that these properties need to be set very early, before parsing the kernel command-line, as they are read-only properties that the bootloader sets using androidboot kernel arguments. The bootloader's real values cause SafetyNet to fail with an unlocked bootloader and/or custom software because the verified boot chain is broken in that case. Change-Id: I66d23fd91d82906b00d5eb020668f01ae83ec31f fastboot: Revert to Android 11 method of checking lock status Now that we're setting system-wide properties for SafetyNet, which includes ro.boot.verifiedbootstate=green, fastbootd always detects the bootloader as being locked. Revert to the Android 11 method of reading directly from the kernel cmdline to work arround the issue. - Also don't set these in recovery Change-Id: I57f6d48acddb29748778053edf354d7bd8994bd7 --- fastboot/device/utility.cpp | 7 ++++++- init/property_service.cpp | 17 +++++++++++++++++ 2 files changed, 23 insertions(+), 1 deletion(-) diff --git a/fastboot/device/utility.cpp b/fastboot/device/utility.cpp index b8b3119ac..f9267e0eb 100644 --- a/fastboot/device/utility.cpp +++ b/fastboot/device/utility.cpp @@ -204,7 +204,12 @@ std::vector ListPartitions(FastbootDevice* device) { } bool GetDeviceLockStatus() { - return android::base::GetProperty("ro.boot.verifiedbootstate", "") == "green"; + std::string cmdline; + // Return lock status true if unable to read kernel command line. + if (!android::base::ReadFileToString("/proc/cmdline", &cmdline)) { + return true; + } + return cmdline.find("androidboot.verifiedbootstate=orange") == std::string::npos; } bool UpdateAllPartitionMetadata(FastbootDevice* device, const std::string& super_name, diff --git a/init/property_service.cpp b/init/property_service.cpp index d429fc762..c73a2fa5d 100644 --- a/init/property_service.cpp +++ b/init/property_service.cpp @@ -1251,6 +1251,15 @@ static void ProcessBootconfig() { }); } +static void SetSafetyNetProps() { + InitPropertySet("ro.boot.flash.locked", "1"); + InitPropertySet("ro.boot.verifiedbootstate", "green"); + InitPropertySet("ro.boot.veritymode", "enforcing"); + InitPropertySet("ro.boot.vbmeta.device_state", "locked"); + InitPropertySet("ro.boot.warranty_bit", "0"); + InitPropertySet("ro.warranty_bit", "0"); +} + void PropertyInit() { selinux_callback cb; cb.func_audit = PropertyAuditCallback; @@ -1265,6 +1274,14 @@ void PropertyInit() { LOG(FATAL) << "Failed to load serialized property info file"; } + // Report a valid verified boot chain to make Google SafetyNet integrity + // checks pass. This needs to be done before parsing the kernel cmdline as + // these properties are read-only and will be set to invalid values with + // androidboot cmdline arguments. + if (!IsRecoveryMode()) { + SetSafetyNetProps(); + } + // If arguments are passed both on the command line and in DT, // properties set in DT always have priority over the command-line ones. ProcessKernelDt();