Merge "liblog: Add __android_log_security()" (1631d36d) · Commits · e / os / android_system_core

include/log/log.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -620,6 +620,8 @@ typedef enum log_id {
		*/
		int __android_log_is_loggable(int prio, const char *tag, int default_prio);

		int __android_log_security(); /* Device Owner is present */

		int __android_log_error_write(int tag, const char subTag, int32_t uid, const char data,
		uint32_t dataLen);

liblog/log_is_loggable.c

+48 −1

Original line number	Diff line number	Diff line
		@@ -45,6 +45,9 @@ struct cache {
		char c;
		};

		#define BOOLEAN_TRUE 0xFF
		#define BOOLEAN_FALSE 0xFE

		static void refresh_cache(struct cache cache, const char key)
		{
		uint32_t serial;
		@@ -62,8 +65,17 @@ static void refresh_cache(struct cache cache, const char key)
		}
		cache->serial = serial;
		__system_property_read(cache->pinfo, 0, buf);
		switch(buf[0]) {
		case 't': case 'T':
		cache->c = strcasecmp(buf + 1, "rue") ? buf[0] : BOOLEAN_TRUE;
		break;
		case 'f': case 'F':
		cache->c = strcasecmp(buf + 1, "alse") ? buf[0] : BOOLEAN_FALSE;
		break;
		default:
		cache->c = buf[0];
		}
		}

		static int __android_log_level(const char *tag, int default_prio)
		{
		@@ -147,6 +159,7 @@ static int __android_log_level(const char *tag, int default_prio)
		case 'F': /* Not officially supported */
		case 'A':
		case 'S':
		case BOOLEAN_FALSE: /* Not officially supported */
		break;
		default:
		/* clear '.' after log.tag */
		@@ -180,6 +193,7 @@ static int __android_log_level(const char *tag, int default_prio)
		case 'E': return ANDROID_LOG_ERROR;
		case 'F': /* FALLTHRU / / Not officially supported */
		case 'A': return ANDROID_LOG_FATAL;
		case BOOLEAN_FALSE: /* FALLTHRU / / Not Officially supported */
		case 'S': return -1; /* ANDROID_LOG_SUPPRESS */
		}
		return default_prio;
		@@ -226,3 +240,36 @@ clockid_t android_log_clockid()

		return (tolower(c) == 'm') ? CLOCK_MONOTONIC : CLOCK_REALTIME;
		}

		/*
		* security state generally remains constant, since a change is
		* rare, we can accept a trylock failure gracefully.
		*/
		static pthread_mutex_t lock_security = PTHREAD_MUTEX_INITIALIZER;

		int __android_log_security()
		{
		static struct cache r_do_cache = { NULL, -1, BOOLEAN_FALSE };
		static struct cache p_security_cache = { NULL, -1, BOOLEAN_FALSE };
		int retval;

		if (pthread_mutex_trylock(&lock_security)) {
		/* We are willing to accept some race in this context */
		retval = (r_do_cache.c != BOOLEAN_FALSE) && r_do_cache.c &&
		(p_security_cache.c == BOOLEAN_TRUE);
		} else {
		static uint32_t serial;
		uint32_t current_serial = __system_property_area_serial();
		if (current_serial != serial) {
		refresh_cache(&r_do_cache, "ro.device_owner");
		refresh_cache(&p_security_cache, "persist.logd.security");
		serial = current_serial;
		}
		retval = (r_do_cache.c != BOOLEAN_FALSE) && r_do_cache.c &&
		(p_security_cache.c == BOOLEAN_TRUE);

		pthread_mutex_unlock(&lock_security);
		}

		return retval;
		}

liblog/tests/liblog_test.cpp

+37 −0

Original line number	Diff line number	Diff line
		@@ -164,6 +164,43 @@ TEST(liblog, __android_log_btwrite__android_logger_list_read) {
		android_logger_list_close(logger_list);
		}

		TEST(liblog, __security) {
		static const char persist_key[] = "persist.logd.security";
		static const char readonly_key[] = "ro.device_owner";
		static const char nothing_val[] = "_NOTHING_TO_SEE_HERE_";
		char persist[PROP_VALUE_MAX];
		char readonly[PROP_VALUE_MAX];

		property_get(persist_key, persist, "");
		property_get(readonly_key, readonly, nothing_val);

		if (!strcmp(readonly, nothing_val)) {
		EXPECT_FALSE(__android_log_security());
		fprintf(stderr, "Warning, setting ro.device_owner to a domain\n");
		property_set(readonly_key, "com.google.android.SecOps.DeviceOwner");
		} else if (!strcasecmp(readonly, "false") \|\| !readonly[0]) {
		EXPECT_FALSE(__android_log_security());
		return;
		}

		if (!strcasecmp(persist, "true")) {
		EXPECT_TRUE(__android_log_security());
		} else {
		EXPECT_FALSE(__android_log_security());
		}
		property_set(persist_key, "TRUE");
		EXPECT_TRUE(__android_log_security());
		property_set(persist_key, "FALSE");
		EXPECT_FALSE(__android_log_security());
		property_set(persist_key, "true");
		EXPECT_TRUE(__android_log_security());
		property_set(persist_key, "false");
		EXPECT_FALSE(__android_log_security());
		property_set(persist_key, "");
		EXPECT_FALSE(__android_log_security());
		property_set(persist_key, persist);
		}

		static unsigned signaled;
		log_time signal_time;