Merge "logd: enforce policy integrity" (d1ac9323) · Commits · e / os / android_system_core

logd/Android.mk

+4 −0

Original line number	Original line	Diff line number	Diff line
	@@ -42,6 +42,10 @@ event_flag := -DAUDITD_LOG_TAG=1003 -DLOGD_LOG_TAG=1004

	LOCAL_CFLAGS := -Werror $(event_flag)		LOCAL_CFLAGS := -Werror $(event_flag)

			ifeq ($(TARGET_BUILD_VARIANT),user)
			LOCAL_CFLAGS += -DAUDITD_ENFORCE_INTEGRITY=true
			endif

	include $(BUILD_EXECUTABLE)		include $(BUILD_EXECUTABLE)

	include $(call first-makefiles-under,$(LOCAL_PATH))		include $(call first-makefiles-under,$(LOCAL_PATH))

logd/LogAudit.cpp

+69 −5

Original line number	Original line	Diff line number	Diff line
	@@ -24,6 +24,7 @@
	#include <sys/uio.h>		#include <sys/uio.h>
	#include <syslog.h>		#include <syslog.h>

			#include <cutils/properties.h>
	#include <log/logger.h>		#include <log/logger.h>
	#include <private/android_filesystem_config.h>		#include <private/android_filesystem_config.h>
	#include <private/android_logger.h>		#include <private/android_logger.h>
	@@ -32,6 +33,10 @@
	#include "LogAudit.h"		#include "LogAudit.h"
	#include "LogKlog.h"		#include "LogKlog.h"

			#ifndef AUDITD_ENFORCE_INTEGRITY
			#define AUDITD_ENFORCE_INTEGRITY false
			#endif

	#define KMSG_PRIORITY(PRI) \		#define KMSG_PRIORITY(PRI) \
	'<', \		'<', \
	'0' + LOG_MAKEPRI(LOG_AUTH, LOG_PRI(PRI)) / 10, \		'0' + LOG_MAKEPRI(LOG_AUTH, LOG_PRI(PRI)) / 10, \
	@@ -43,11 +48,10 @@ LogAudit::LogAudit(LogBuffer buf, LogReader reader, int fdDmesg) :
	logbuf(buf),		logbuf(buf),
	reader(reader),		reader(reader),
	fdDmesg(fdDmesg),		fdDmesg(fdDmesg),
			policyLoaded(false),
			rebootToSafeMode(false),
	initialized(false) {		initialized(false) {
	static const char auditd_message[] = { KMSG_PRIORITY(LOG_INFO),		logToDmesg("start");
	'l', 'o', 'g', 'd', '.', 'a', 'u', 'd', 'i', 't', 'd', ':',
	' ', 's', 't', 'a', 'r', 't', '\n' };
	write(fdDmesg, auditd_message, sizeof(auditd_message));
	}		}

	bool LogAudit::onDataAvailable(SocketClient *cli) {		bool LogAudit::onDataAvailable(SocketClient *cli) {
	@@ -73,6 +77,46 @@ bool LogAudit::onDataAvailable(SocketClient *cli) {
	return true;		return true;
	}		}

			void LogAudit::logToDmesg(const std::string& str)
			{
			static const char prefix[] = { KMSG_PRIORITY(LOG_INFO),
			'l', 'o', 'g', 'd', '.', 'a', 'u', 'd', 'i', 't', 'd', ':',
			' ', '\0' };
			std::string message = prefix + str + "\n";
			write(fdDmesg, message.c_str(), message.length());
			}

			std::string LogAudit::getProperty(const std::string& name)
			{
			char value[PROP_VALUE_MAX] = {0};
			property_get(name.c_str(), value, "");
			return value;
			}

			void LogAudit::enforceIntegrity() {
			if (!AUDITD_ENFORCE_INTEGRITY) {
			logToDmesg("integrity enforcement suppressed; not rebooting");
			} else if (rebootToSafeMode) {
			if (getProperty("persist.sys.safemode") == "1") {
			logToDmesg("integrity enforcement suppressed; in safe mode");
			return;
			}

			logToDmesg("enforcing integrity; rebooting to safe mode");
			property_set("persist.sys.safemode", "1");

			std::string buildDate = getProperty("ro.build.date.utc");
			if (!buildDate.empty()) {
			property_set("persist.sys.audit_safemode", buildDate.c_str());
			}

			property_set("sys.powerctl", "reboot");
			} else {
			logToDmesg("enforcing integrity: rebooting to recovery");
			property_set("sys.powerctl", "reboot,recovery");
			}
			}

	int LogAudit::logPrint(const char *fmt, ...) {		int LogAudit::logPrint(const char *fmt, ...) {
	if (fmt == NULL) {		if (fmt == NULL) {
	return -EINVAL;		return -EINVAL;
	@@ -94,7 +138,27 @@ int LogAudit::logPrint(const char *fmt, ...) {
	memmove(cp, cp + 1, strlen(cp + 1) + 1);		memmove(cp, cp + 1, strlen(cp + 1) + 1);
	}		}

	bool info = strstr(str, " permissive=1") \|\| strstr(str, " policy loaded ");		bool loaded = strstr(str, " policy loaded ");

			if (loaded) {
			if (policyLoaded) {
			// SELinux policy changes are not allowed
			enforceIntegrity();
			} else {
			logToDmesg("policy loaded");
			policyLoaded = true;
			}
			}

			bool permissive = strstr(str, " enforcing=0") \|\|
			strstr(str, " permissive=1");

			if (permissive) {
			// SELinux in permissive mode is not allowed
			enforceIntegrity();
			}

			bool info = loaded \|\| permissive;
	if ((fdDmesg >= 0) && initialized) {		if ((fdDmesg >= 0) && initialized) {
	struct iovec iov[3];		struct iovec iov[3];
	static const char log_info[] = { KMSG_PRIORITY(LOG_INFO) };		static const char log_info[] = { KMSG_PRIORITY(LOG_INFO) };

logd/LogAudit.h

+6 −0

Original line number	Original line	Diff line number	Diff line
	@@ -24,12 +24,15 @@ class LogAudit : public SocketListener {
	LogBuffer *logbuf;		LogBuffer *logbuf;
	LogReader *reader;		LogReader *reader;
	int fdDmesg;		int fdDmesg;
			bool policyLoaded;
			bool rebootToSafeMode;
	bool initialized;		bool initialized;

	public:		public:
	LogAudit(LogBuffer buf, LogReader reader, int fdDmesg);		LogAudit(LogBuffer buf, LogReader reader, int fdDmesg);
	int log(char *buf, size_t len);		int log(char *buf, size_t len);
	bool isMonotonic() { return logbuf->isMonotonic(); }		bool isMonotonic() { return logbuf->isMonotonic(); }
			void allowSafeMode(bool allow = true) { rebootToSafeMode = allow; }

	protected:		protected:
	virtual bool onDataAvailable(SocketClient *cli);		virtual bool onDataAvailable(SocketClient *cli);
	@@ -38,6 +41,9 @@ private:
	static int getLogSocket();		static int getLogSocket();
	int logPrint(const char *fmt, ...)		int logPrint(const char *fmt, ...)
	__attribute__ ((__format__ (__printf__, 2, 3)));		__attribute__ ((__format__ (__printf__, 2, 3)));
			void logToDmesg(const std::string& str);
			std::string getProperty(const std::string& name);
			void enforceIntegrity();
	};		};

	#endif		#endif

logd/README.property

+0 −1

Original line number	Original line	Diff line number	Diff line
	The properties that logd responds to are:		The properties that logd responds to are:

	name type default description		name type default description
	ro.logd.auditd bool true Enable selinux audit daemon
	ro.logd.auditd.dmesg bool true selinux audit messages duplicated and		ro.logd.auditd.dmesg bool true selinux audit messages duplicated and
	sent on to dmesg log		sent on to dmesg log
	persist.logd.security bool false Enable security buffer.		persist.logd.security bool false Enable security buffer.

logd/main.cpp

+16 −16

Original line number	Original line	Diff line number	Diff line
	@@ -245,6 +245,7 @@ static char *name;
	static sem_t reinit;		static sem_t reinit;
	static bool reinit_running = false;		static bool reinit_running = false;
	static LogBuffer *logBuf = NULL;		static LogBuffer *logBuf = NULL;
			static LogAudit *logAudit = NULL;

	static bool package_list_parser_cb(pkg_info info, void /* userdata */) {		static bool package_list_parser_cb(pkg_info info, void /* userdata */) {

	@@ -292,6 +293,10 @@ static void reinit_thread_start(void /obj/) {
	logBuf->init();		logBuf->init();
	logBuf->initPrune(NULL);		logBuf->initPrune(NULL);
	}		}

			if (logAudit) {
			logAudit->allowSafeMode();
			}
	}		}

	return NULL;		return NULL;
	@@ -512,25 +517,19 @@ int main(int argc, char *argv[]) {
	// initiated log messages. New log entries are added to LogBuffer		// initiated log messages. New log entries are added to LogBuffer
	// and LogReader is notified to send updates to connected clients.		// and LogReader is notified to send updates to connected clients.

	bool auditd = property_get_bool("logd.auditd",		logAudit = new LogAudit(logBuf, reader,
	BOOL_DEFAULT_TRUE \|
	BOOL_DEFAULT_FLAG_PERSIST);
	LogAudit *al = NULL;
	if (auditd) {
	al = new LogAudit(logBuf, reader,
	property_get_bool("logd.auditd.dmesg",		property_get_bool("logd.auditd.dmesg",
	BOOL_DEFAULT_TRUE \|		BOOL_DEFAULT_TRUE \|
	BOOL_DEFAULT_FLAG_PERSIST)		BOOL_DEFAULT_FLAG_PERSIST)
	? fdDmesg		? fdDmesg
	: -1);		: -1);
	}

	LogKlog *kl = NULL;		LogKlog *kl = NULL;
	if (klogd) {		if (klogd) {
	kl = new LogKlog(logBuf, reader, fdDmesg, fdPmesg, al != NULL);		kl = new LogKlog(logBuf, reader, fdDmesg, fdPmesg, logAudit != NULL);
	}		}

	readDmesg(al, kl);		readDmesg(logAudit, kl);

	// failure is an option ... messages are in dmesg (required by standard)		// failure is an option ... messages are in dmesg (required by standard)

	@@ -538,8 +537,9 @@ int main(int argc, char *argv[]) {
	delete kl;		delete kl;
	}		}

	if (al && al->startListener()) {		if (logAudit && logAudit->startListener()) {
	delete al;		delete logAudit;
			logAudit = NULL;
	}		}

	TEMP_FAILURE_RETRY(pause());		TEMP_FAILURE_RETRY(pause());