1 #include <errno.h> 2 #include <sys/capability.h> 3 #include <sys/prctl.h> 4 #include <sys/stat.h> 5 6 #include <cutils/properties.h> 7 #include <cutils/sched_policy.h> 8 #include <log/log.h> 9 #include <sys/resource.h> 10 #include <utils/threads.h> 11 12 #include <pdx/service_dispatcher.h> 13 #include <private/android_filesystem_config.h> 14 15 #include "performance_service.h" 16 17 namespace { 18 19 // Annoying that sys/capability.h doesn't define this directly. 20 constexpr int kMaxCapNumber = (CAP_TO_INDEX(CAP_LAST_CAP) + 1); 21 22 } // anonymous namespace 23 24 int main(int /*argc*/, char** /*argv*/) { 25 int ret = -1; 26 27 struct __user_cap_header_struct capheader; 28 struct __user_cap_data_struct capdata[kMaxCapNumber]; 29 30 std::shared_ptr<android::pdx::Service> service; 31 std::unique_ptr<android::pdx::ServiceDispatcher> dispatcher; 32 33 ALOGI("Starting up..."); 34 35 // We need to be able to create endpoints with full perms. 36 umask(0000); 37 38 // Keep capabilities when switching UID to AID_SYSTEM. 39 ret = prctl(PR_SET_KEEPCAPS, 1, 0, 0, 0); 40 CHECK_ERROR(ret < 0, error, "Failed to set KEEPCAPS: %s", strerror(errno)); 41 42 // Set UID and GID to system. 43 ret = setresgid(AID_SYSTEM, AID_SYSTEM, AID_SYSTEM); 44 CHECK_ERROR(ret < 0, error, "Failed to set GID: %s", strerror(errno)); 45 ret = setresuid(AID_SYSTEM, AID_SYSTEM, AID_SYSTEM); 46 CHECK_ERROR(ret < 0, error, "Failed to set UID: %s", strerror(errno)); 47 48 // Keep CAP_SYS_NICE, allowing control of scheduler class, priority, and 49 // cpuset for other tasks in the system. 50 memset(&capheader, 0, sizeof(capheader)); 51 memset(&capdata, 0, sizeof(capdata)); 52 capheader.version = _LINUX_CAPABILITY_VERSION_3; 53 capdata[CAP_TO_INDEX(CAP_SYS_NICE)].effective |= CAP_TO_MASK(CAP_SYS_NICE); 54 capdata[CAP_TO_INDEX(CAP_SYS_NICE)].permitted |= CAP_TO_MASK(CAP_SYS_NICE); 55 56 // Drop all caps but the ones configured above. 57 ret = capset(&capheader, capdata); 58 CHECK_ERROR(ret < 0, error, "Could not set capabilities: %s", 59 strerror(errno)); 60 61 dispatcher = android::pdx::ServiceDispatcher::Create(); 62 CHECK_ERROR(!dispatcher, error, "Failed to create service dispatcher."); 63 64 service = android::dvr::PerformanceService::Create(); 65 CHECK_ERROR(!service, error, "Failed to create performance service service."); 66 dispatcher->AddService(service); 67 68 ALOGI("Entering message loop."); 69 70 ret = dispatcher->EnterDispatchLoop(); 71 CHECK_ERROR(ret < 0, error, "Dispatch loop exited because: %s\n", 72 strerror(-ret)); 73 74 error: 75 return ret; 76 } 77
