Merge "Add evaluate domain name callback in DnsResolver" (2af22b1b) · Commits · e / os / android_packages_modules_DnsResolver

DnsProxyListener.cpp

+25 −5

Original line number	Original line	Diff line number	Diff line
	@@ -535,6 +535,13 @@ DnsProxyListener::GetAddrInfoHandler::~GetAddrInfoHandler() {
	free(mHints);		free(mHints);
	}		}

			static bool evaluate_domain_name(const android_net_context &netcontext,
			const char *host) {
			if (!gResNetdCallbacks.evaluate_domain_name)
			return true;
			return gResNetdCallbacks.evaluate_domain_name(netcontext, host);
			}

	static bool sendBE32(SocketClient* c, uint32_t data) {		static bool sendBE32(SocketClient* c, uint32_t data) {
	uint32_t be_data = htonl(data);		uint32_t be_data = htonl(data);
	return c->sendData(&be_data, sizeof(be_data)) == 0;		return c->sendData(&be_data, sizeof(be_data)) == 0;
	@@ -672,7 +679,12 @@ void DnsProxyListener::GetAddrInfoHandler::run() {
	NetworkDnsEventReported event;		NetworkDnsEventReported event;
	initDnsEvent(&event);		initDnsEvent(&event);
	if (queryLimiter.start(uid)) {		if (queryLimiter.start(uid)) {
	rv = resolv_getaddrinfo(mHost, mService, mHints, &mNetContext, &result, &event);		if (evaluate_domain_name(mNetContext, mHost)) {
			rv = resolv_getaddrinfo(mHost, mService, mHints, &mNetContext, &result,
			&event);
			} else {
			rv = EAI_SYSTEM;
			}
	queryLimiter.finish(uid);		queryLimiter.finish(uid);
	} else {		} else {
	// Note that this error code is currently not passed down to the client.		// Note that this error code is currently not passed down to the client.
	@@ -887,8 +899,12 @@ void DnsProxyListener::ResNSendHandler::run() {
	NetworkDnsEventReported event;		NetworkDnsEventReported event;
	initDnsEvent(&event);		initDnsEvent(&event);
	if (queryLimiter.start(uid)) {		if (queryLimiter.start(uid)) {
			if (evaluate_domain_name(mNetContext, rr_name.c_str())) {
	nsendAns = resolv_res_nsend(&mNetContext, msg.data(), msgLen, ansBuf.data(), MAXPACKET,		nsendAns = resolv_res_nsend(&mNetContext, msg.data(), msgLen, ansBuf.data(), MAXPACKET,
	&rcode, static_cast<ResNsendFlags>(mFlags), &event);		&rcode, static_cast<ResNsendFlags>(mFlags), &event);
			} else {
			nsendAns = -EAI_SYSTEM;
			}
	queryLimiter.finish(uid);		queryLimiter.finish(uid);
	} else {		} else {
	LOG(WARNING) << "ResNSendHandler::run: resnsend: from UID " << uid		LOG(WARNING) << "ResNSendHandler::run: resnsend: from UID " << uid
	@@ -1080,8 +1096,12 @@ void DnsProxyListener::GetHostByNameHandler::run() {
	NetworkDnsEventReported event;		NetworkDnsEventReported event;
	initDnsEvent(&event);		initDnsEvent(&event);
	if (queryLimiter.start(uid)) {		if (queryLimiter.start(uid)) {
			if (evaluate_domain_name(mNetContext, mName)) {
	rv = resolv_gethostbyname(mName, mAf, &hbuf, tmpbuf, sizeof tmpbuf, &mNetContext, &hp,		rv = resolv_gethostbyname(mName, mAf, &hbuf, tmpbuf, sizeof tmpbuf, &mNetContext, &hp,
	&event);		&event);
			} else {
			rv = EAI_SYSTEM;
			}
	queryLimiter.finish(uid);		queryLimiter.finish(uid);
	} else {		} else {
	rv = EAI_MEMORY;		rv = EAI_MEMORY;

DnsResolver.cpp

+1 −0

Original line number	Original line	Diff line number	Diff line
	@@ -38,6 +38,7 @@ bool resolv_init(const ResolverNetdCallbacks* callbacks) {
	gResNetdCallbacks.log = callbacks->log;		gResNetdCallbacks.log = callbacks->log;
	if (gApiLevel >= 30) {		if (gApiLevel >= 30) {
	gResNetdCallbacks.tagSocket = callbacks->tagSocket;		gResNetdCallbacks.tagSocket = callbacks->tagSocket;
			gResNetdCallbacks.evaluate_domain_name = callbacks->evaluate_domain_name;
	}		}
	android::net::gDnsResolv = android::net::DnsResolver::getInstance();		android::net::gDnsResolv = android::net::DnsResolver::getInstance();
	return android::net::gDnsResolv->start();		return android::net::gDnsResolv->start();

include/netd_resolv/resolv.h

+24 −0

Original line number	Original line	Diff line number	Diff line
	@@ -81,6 +81,29 @@ typedef void (*get_network_context_callback)(unsigned netid, uid_t uid,
	typedef void (log_callback)(const char msg);		typedef void (log_callback)(const char msg);
	typedef int (*tagSocketCallback)(int sockFd, uint32_t tag, uid_t uid, pid_t pid);		typedef int (*tagSocketCallback)(int sockFd, uint32_t tag, uid_t uid, pid_t pid);

			// The DnsResolver module invokes this callback once before starting each DNS
			// lookup. The callback receives the android_net_context associated with the
			// request, and the (possibly unqualified) hostname requested by the app via
			// getaddrinfo() or gethostbyname().
			//
			// If the callback returns false, the DnsResolver will abort the request
			// returning EAI_SYSTEM. If the callback returns true, the query will proceed as
			// usual.
			//
			// If this callback is not present (i.e. set to nullptr), the effect is the same
			// of returning true.
			//
			// This callback will be invoked concurrently from multiple threads. It must
			// peform its own locking when accessing shared data structures. Furthermore,
			// the callback must not sleep nor perform RPC requests.
			//
			// Be mindful that hostnames could contain sensitive user data. Do not log them
			// and do not transmit them to third parties without explicit user
			// authorization.
			//
			typedef bool (*evaluate_domain_name_callback)(
			const android_net_context &netcontext, const char *host);

	/*		/*
	* Some functions needed by the resolver (e.g. checkCallingPermission()) live in		* Some functions needed by the resolver (e.g. checkCallingPermission()) live in
	* libraries with no ABI stability guarantees, such as libbinder.so.		* libraries with no ABI stability guarantees, such as libbinder.so.
	@@ -92,6 +115,7 @@ struct ResolverNetdCallbacks {
	get_network_context_callback get_network_context;		get_network_context_callback get_network_context;
	log_callback log;		log_callback log;
	tagSocketCallback tagSocket;		tagSocketCallback tagSocket;
			evaluate_domain_name_callback evaluate_domain_name;
	};		};

	#define TAG_SYSTEM_DNS 0xFFFFFF82		#define TAG_SYSTEM_DNS 0xFFFFFF82