Refactor ResState to store nameserver addresses by IPSockAddr am: e48f7b54a5 am: 514b91fb46 (cd4ad767) · Commits · e / os / android_packages_modules_DnsResolver

res_cache.cpp

+6 −19

Original line number	Original line	Diff line number	Diff line
	@@ -1671,21 +1671,8 @@ void resolv_populate_res_for_net(ResState* statp) {
	NetConfig* info = find_netconfig_locked(statp->netid);		NetConfig* info = find_netconfig_locked(statp->netid);
	if (info == nullptr) return;		if (info == nullptr) return;

	// TODO: Convert nsaddrs[] to c++ container and remove the size-checking.		statp->nscount = static_cast<int>(info->nameserverSockAddrs.size());
	const int serverNum = std::min(MAXNS, static_cast<int>(info->nameserverSockAddrs.size()));		statp->nsaddrs = info->nameserverSockAddrs;

	for (int nserv = 0; nserv < serverNum; nserv++) {
	sockaddr_storage ss = info->nameserverSockAddrs.at(nserv);

	if (auto sockaddr_len = sockaddrSize(ss); sockaddr_len != 0) {
	memcpy(&statp->nsaddrs[nserv], &ss, sockaddr_len);
	} else {
	LOG(WARNING) << __func__ << ": can't get sa_len from "
	<< info->nameserverSockAddrs.at(nserv);
	}
	}

	statp->nscount = serverNum;
	statp->search_domains = info->search_domains;		statp->search_domains = info->search_domains;
	statp->tc_mode = info->tc_mode;		statp->tc_mode = info->tc_mode;
	}		}
	@@ -1811,18 +1798,18 @@ int resolv_cache_get_resolver_stats(unsigned netid, res_params* params, res_stat
	return -1;		return -1;
	}		}

	void resolv_cache_add_resolver_stats_sample(unsigned netid, int revision_id, const sockaddr* sa,		void resolv_cache_add_resolver_stats_sample(unsigned netid, int revision_id,
			const IPSockAddr& serverSockAddr,
	const res_sample& sample, int max_samples) {		const res_sample& sample, int max_samples) {
	if (max_samples <= 0 \|\| sa == nullptr) return;		if (max_samples <= 0) return;

	std::lock_guard guard(cache_mutex);		std::lock_guard guard(cache_mutex);
	NetConfig* info = find_netconfig_locked(netid);		NetConfig* info = find_netconfig_locked(netid);

	if (info && info->revision_id == revision_id) {		if (info && info->revision_id == revision_id) {
	const int serverNum = std::min(MAXNS, static_cast<int>(info->nameserverSockAddrs.size()));		const int serverNum = std::min(MAXNS, static_cast<int>(info->nameserverSockAddrs.size()));
	const IPSockAddr ipsa = IPSockAddr::toIPSockAddr(*sa);
	for (int ns = 0; ns < serverNum; ns++) {		for (int ns = 0; ns < serverNum; ns++) {
	if (ipsa == info->nameserverSockAddrs.at(ns)) {		if (serverSockAddr == info->nameserverSockAddrs[ns]) {
	res_cache_add_stats_sample_locked(&info->nsstats[ns], sample, max_samples);		res_cache_add_stats_sample_locked(&info->nsstats[ns], sample, max_samples);
	return;		return;
	}		}

res_init.cpp

+1 −10

Original line number	Original line	Diff line number	Diff line
	@@ -97,17 +97,8 @@ void res_init(ResState* statp, const struct android_net_context* _Nonnull netcon
	statp->netid = netcontext->dns_netid;		statp->netid = netcontext->dns_netid;
	statp->uid = netcontext->uid;		statp->uid = netcontext->uid;
	statp->pid = netcontext->pid;		statp->pid = netcontext->pid;
	statp->nscount = 1;		statp->nscount = 0;
	statp->id = arc4random_uniform(65536);		statp->id = arc4random_uniform(65536);
	// The following dummy initialization is probably useless because
	// it's overwritten later by resolv_populate_res_for_net().
	// TODO: check if it's safe to remove.
	const sockaddr_union u{
	.sin.sin_addr.s_addr = INADDR_ANY,
	.sin.sin_family = AF_INET,
	.sin.sin_port = htons(NAMESERVER_PORT),
	};
	memcpy(&statp->nsaddrs, &u, sizeof(u));

	for (auto& sock : statp->nssocks) {		for (auto& sock : statp->nssocks) {
	sock.reset();		sock.reset();

res_send.cpp

+40 −35

Original line number	Original line	Diff line number	Diff line
	@@ -138,11 +138,13 @@ using android::netdutils::Stopwatch;

	static DnsTlsDispatcher sDnsTlsDispatcher;		static DnsTlsDispatcher sDnsTlsDispatcher;

	static struct sockaddr* get_nsaddr(res_state, size_t);		static int send_vc(res_state statp, res_params* params, const uint8_t* buf, int buflen,
	static int send_vc(res_state, res_params* params, const uint8_t, int, uint8_t, int, int*, int,		uint8_t* ans, int anssiz, int* terrno, size_t ns, time_t* at, int* rcode,
	time_t, int, int*);		int* delay);
	static int send_dg(res_state, res_params* params, const uint8_t, int, uint8_t, int, int*, int,		static int send_dg(res_state statp, res_params* params, const uint8_t* buf, int buflen,
	int, int, time_t, int, int*);		uint8_t* ans, int anssiz, int* terrno, size_t ns, int* v_circuit,
			int* gotsomewhere, time_t* at, int* rcode, int* delay);

	static void dump_error(const char, const struct sockaddr, int);		static void dump_error(const char, const struct sockaddr, int);

	static int sock_eq(struct sockaddr, struct sockaddr);		static int sock_eq(struct sockaddr, struct sockaddr);
	@@ -288,13 +290,13 @@ static void res_set_usable_server(int selectedServer, int nscount, bool usable_s
	static bool res_ourserver_p(res_state statp, const sockaddr* sa) {		static bool res_ourserver_p(res_state statp, const sockaddr* sa) {
	const sockaddr_in inp, srv;		const sockaddr_in inp, srv;
	const sockaddr_in6 in6p, srv6;		const sockaddr_in6 in6p, srv6;
	int ns;

	switch (sa->sa_family) {		switch (sa->sa_family) {
	case AF_INET:		case AF_INET:
	inp = (const struct sockaddr_in) (const void) sa;		inp = (const struct sockaddr_in) (const void) sa;
	for (ns = 0; ns < statp->nscount; ns++) {		for (const IPSockAddr& ipsa : statp->nsaddrs) {
	srv = (struct sockaddr_in) (void) get_nsaddr(statp, (size_t) ns);		sockaddr_storage ss = ipsa;
			srv = reinterpret_cast<sockaddr_in*>(&ss);
	if (srv->sin_family == inp->sin_family && srv->sin_port == inp->sin_port &&		if (srv->sin_family == inp->sin_family && srv->sin_port == inp->sin_port &&
	(srv->sin_addr.s_addr == INADDR_ANY \|\|		(srv->sin_addr.s_addr == INADDR_ANY \|\|
	srv->sin_addr.s_addr == inp->sin_addr.s_addr))		srv->sin_addr.s_addr == inp->sin_addr.s_addr))
	@@ -303,8 +305,9 @@ static bool res_ourserver_p(res_state statp, const sockaddr* sa) {
	break;		break;
	case AF_INET6:		case AF_INET6:
	in6p = (const struct sockaddr_in6) (const void) sa;		in6p = (const struct sockaddr_in6) (const void) sa;
	for (ns = 0; ns < statp->nscount; ns++) {		for (const IPSockAddr& ipsa : statp->nsaddrs) {
	srv6 = (struct sockaddr_in6) (void) get_nsaddr(statp, (size_t) ns);		sockaddr_storage ss = ipsa;
			srv6 = reinterpret_cast<sockaddr_in6*>(&ss);
	if (srv6->sin6_family == in6p->sin6_family && srv6->sin6_port == in6p->sin6_port &&		if (srv6->sin6_family == in6p->sin6_family && srv6->sin6_port == in6p->sin6_port &&
	#ifdef HAVE_SIN6_SCOPE_ID		#ifdef HAVE_SIN6_SCOPE_ID
	(srv6->sin6_scope_id == 0 \|\| srv6->sin6_scope_id == in6p->sin6_scope_id) &&		(srv6->sin6_scope_id == 0 \|\| srv6->sin6_scope_id == in6p->sin6_scope_id) &&
	@@ -484,20 +487,15 @@ int res_nsend(res_state statp, const uint8_t* buf, int buflen, uint8_t* ans, int
	int terrno = ETIMEDOUT;		int terrno = ETIMEDOUT;

	for (int attempt = 0; attempt < retryTimes; ++attempt) {		for (int attempt = 0; attempt < retryTimes; ++attempt) {
	for (int ns = 0; ns < statp->nscount; ++ns) {		for (size_t ns = 0; ns < statp->nsaddrs.size(); ++ns) {
	if (!usable_servers[ns]) continue;		if (!usable_servers[ns]) continue;

	*rcode = RCODE_INTERNAL_ERROR;		*rcode = RCODE_INTERNAL_ERROR;

	// Get server addr		// Get server addr
	const sockaddr* nsap = get_nsaddr(statp, ns);		const IPSockAddr& serverSockAddr = statp->nsaddrs[ns];
	const int nsaplen = sockaddrSize(nsap);

	static const int niflags = NI_NUMERICHOST \| NI_NUMERICSERV;
	char abuf[NI_MAXHOST];
	if (getnameinfo(nsap, (socklen_t)nsaplen, abuf, sizeof(abuf), NULL, 0, niflags) == 0)
	LOG(DEBUG) << __func__ << ": Querying server (# " << ns + 1		LOG(DEBUG) << __func__ << ": Querying server (# " << ns + 1
	<< ") address = " << abuf;		<< ") address = " << serverSockAddr.toString();

	::android::net::Protocol query_proto = useTcp ? PROTO_TCP : PROTO_UDP;		::android::net::Protocol query_proto = useTcp ? PROTO_TCP : PROTO_UDP;
	time_t now = 0;		time_t now = 0;
	@@ -533,7 +531,7 @@ int res_nsend(res_state statp, const uint8_t* buf, int buflen, uint8_t* ans, int
	dnsQueryEvent->set_cache_hit(static_cast<CacheStatus>(cache_status));		dnsQueryEvent->set_cache_hit(static_cast<CacheStatus>(cache_status));
	dnsQueryEvent->set_latency_micros(saturate_cast<int32_t>(queryStopwatch.timeTakenUs()));		dnsQueryEvent->set_latency_micros(saturate_cast<int32_t>(queryStopwatch.timeTakenUs()));
	dnsQueryEvent->set_dns_server_index(ns);		dnsQueryEvent->set_dns_server_index(ns);
	dnsQueryEvent->set_ip_version(ipFamilyToIPVersion(nsap->sa_family));		dnsQueryEvent->set_ip_version(ipFamilyToIPVersion(serverSockAddr.family()));
	dnsQueryEvent->set_retry_times(retry_count_for_event);		dnsQueryEvent->set_retry_times(retry_count_for_event);
	dnsQueryEvent->set_rcode(static_cast<NsRcode>(*rcode));		dnsQueryEvent->set_rcode(static_cast<NsRcode>(*rcode));
	dnsQueryEvent->set_protocol(query_proto);		dnsQueryEvent->set_protocol(query_proto);
	@@ -545,9 +543,9 @@ int res_nsend(res_state statp, const uint8_t* buf, int buflen, uint8_t* ans, int
	if (shouldRecordStats) {		if (shouldRecordStats) {
	res_sample sample;		res_sample sample;
	_res_stats_set_sample(&sample, now, *rcode, delay);		_res_stats_set_sample(&sample, now, *rcode, delay);
	resolv_cache_add_resolver_stats_sample(statp->netid, revision_id, nsap, sample,		resolv_cache_add_resolver_stats_sample(statp->netid, revision_id, serverSockAddr,
	params.max_samples);		sample, params.max_samples);
	resolv_stats_add(statp->netid, IPSockAddr::toIPSockAddr(*nsap), dnsQueryEvent);		resolv_stats_add(statp->netid, serverSockAddr, dnsQueryEvent);
	}		}

	if (resplen == 0) continue;		if (resplen == 0) continue;
	@@ -582,12 +580,6 @@ int res_nsend(res_state statp, const uint8_t* buf, int buflen, uint8_t* ans, int
	return -terrno;		return -terrno;
	}		}

	/* Private */

	static struct sockaddr* get_nsaddr(res_state statp, size_t n) {
	return (struct sockaddr)(void)&statp->nsaddrs[n];
	}

	static struct timespec get_timeout(res_state statp, const res_params* params, const int ns) {		static struct timespec get_timeout(res_state statp, const res_params* params, const int ns) {
	int msec;		int msec;
	// Legacy algorithm which scales the timeout by nameserver number.		// Legacy algorithm which scales the timeout by nameserver number.
	@@ -610,7 +602,7 @@ static struct timespec get_timeout(res_state statp, const res_params* params, co
	}		}

	static int send_vc(res_state statp, res_params* params, const uint8_t* buf, int buflen,		static int send_vc(res_state statp, res_params* params, const uint8_t* buf, int buflen,
	uint8_t* ans, int anssiz, int* terrno, int ns, time_t* at, int* rcode,		uint8_t* ans, int anssiz, int* terrno, size_t ns, time_t* at, int* rcode,
	int* delay) {		int* delay) {
	*at = time(NULL);		*at = time(NULL);
	*delay = 0;		*delay = 0;
	@@ -623,7 +615,14 @@ static int send_vc(res_state statp, res_params* params, const uint8_t* buf, int

	LOG(INFO) << __func__ << ": using send_vc";		LOG(INFO) << __func__ << ": using send_vc";

	nsap = get_nsaddr(statp, (size_t) ns);		// It should never happen, but just in case.
			if (ns >= statp->nsaddrs.size()) {
			LOG(ERROR) << __func__ << ": Out-of-bound indexing: " << ns;
			return -1;
			}

			sockaddr_storage ss = statp->nsaddrs[ns];
			nsap = reinterpret_cast<sockaddr*>(&ss);
	nsaplen = sockaddrSize(nsap);		nsaplen = sockaddrSize(nsap);

	connreset = 0;		connreset = 0;
	@@ -897,12 +896,18 @@ bool ignoreInvalidAnswer(res_state statp, const sockaddr_storage& from, const ui
	}		}

	static int send_dg(res_state statp, res_params* params, const uint8_t* buf, int buflen,		static int send_dg(res_state statp, res_params* params, const uint8_t* buf, int buflen,
	uint8_t* ans, int anssiz, int* terrno, int ns, int* v_circuit, int* gotsomewhere,		uint8_t* ans, int anssiz, int* terrno, size_t ns, int* v_circuit,
	time_t* at, int* rcode, int* delay) {		int* gotsomewhere, time_t* at, int* rcode, int* delay) {
			// It should never happen, but just in case.
			if (ns >= statp->nsaddrs.size()) {
			LOG(ERROR) << __func__ << ": Out-of-bound indexing: " << ns;
			return -1;
			}

	*at = time(nullptr);		*at = time(nullptr);
	*delay = 0;		*delay = 0;
			const sockaddr_storage ss = statp->nsaddrs[ns];
	const sockaddr* nsap = get_nsaddr(statp, (size_t)ns);		const sockaddr* nsap = reinterpret_cast<const sockaddr*>(&ss);
	const int nsaplen = sockaddrSize(nsap);		const int nsaplen = sockaddrSize(nsap);

	if (statp->nssocks[ns] == -1) {		if (statp->nssocks[ns] == -1) {

resolv_cache_unit_test.cpp

+5 −4

resolv_private.h

+5 −2

Original line number	Original line	Diff line number	Diff line
	@@ -55,6 +55,8 @@
	#include <string>		#include <string>
	#include <vector>		#include <vector>

			#include <netdutils/InternetAddresses.h>

	#include "DnsResolver.h"		#include "DnsResolver.h"
	#include "netd_resolv/resolv.h"		#include "netd_resolv/resolv.h"
	#include "params.h"		#include "params.h"
	@@ -102,7 +104,7 @@ struct ResState {
	int nscount; // number of name srvers		int nscount; // number of name srvers
	uint16_t id; // current message id		uint16_t id; // current message id
	std::vector<std::string> search_domains{}; // domains to search		std::vector<std::string> search_domains{}; // domains to search
	sockaddr_union nsaddrs[MAXNS];		std::vector<android::netdutils::IPSockAddr> nsaddrs;
	android::base::unique_fd nssocks[MAXNS]; // UDP sockets to nameservers		android::base::unique_fd nssocks[MAXNS]; // UDP sockets to nameservers
	unsigned ndots : 4; // threshold for initial abs. query		unsigned ndots : 4; // threshold for initial abs. query
	unsigned _mark; // If non-0 SET_MARK to _mark on all request sockets		unsigned _mark; // If non-0 SET_MARK to _mark on all request sockets
	@@ -125,7 +127,8 @@ int resolv_cache_get_resolver_stats(unsigned netid, res_params* params, res_stat
	/* Add a sample to the shared struct for the given netid and server, provided that the		/* Add a sample to the shared struct for the given netid and server, provided that the
	* revision_id of the stored servers has not changed.		* revision_id of the stored servers has not changed.
	*/		*/
	void resolv_cache_add_resolver_stats_sample(unsigned netid, int revision_id, const sockaddr* sa,		void resolv_cache_add_resolver_stats_sample(unsigned netid, int revision_id,
			const android::netdutils::IPSockAddr& serverSockAddr,
	const res_sample& sample, int max_samples);		const res_sample& sample, int max_samples);

	// Calculate the round-trip-time from start time t0 and end time t1.		// Calculate the round-trip-time from start time t0 and end time t1.

Original line number	Original line	Diff line number	Diff line
	@@ -38,6 +38,8 @@

	using namespace std::chrono_literals;		using namespace std::chrono_literals;

			using android::netdutils::IPSockAddr;

	constexpr int TEST_NETID = 30;		constexpr int TEST_NETID = 30;
	constexpr int TEST_NETID_2 = 31;		constexpr int TEST_NETID_2 = 31;
	constexpr int DNS_PORT = 53;		constexpr int DNS_PORT = 53;
	@@ -190,9 +192,9 @@ class ResolvCacheTest : public ::testing::Test {
	return resolv_set_nameservers(netId, setup.servers, setup.domains, setup.params);		return resolv_set_nameservers(netId, setup.servers, setup.domains, setup.params);
	}		}

	void cacheAddStats(uint32_t netId, int revision_id, const sockaddr* sa,		void cacheAddStats(uint32_t netId, int revision_id, const IPSockAddr& ipsa,
	const res_sample& sample, int max_samples) {		const res_sample& sample, int max_samples) {
	resolv_cache_add_resolver_stats_sample(netId, revision_id, sa, sample, max_samples);		resolv_cache_add_resolver_stats_sample(netId, revision_id, ipsa, sample, max_samples);
	}		}

	int cacheFlush(uint32_t netId) { return resolv_flush_cache_for_net(netId); }		int cacheFlush(uint32_t netId) { return resolv_flush_cache_for_net(netId); }
	@@ -735,8 +737,7 @@ TEST_F(ResolvCacheTest, FlushCache) {
	res_sample sample = {.at = time(NULL), .rtt = 100, .rcode = ns_r_noerror};		res_sample sample = {.at = time(NULL), .rtt = 100, .rcode = ns_r_noerror};
	sockaddr_in sin = {.sin_family = AF_INET, .sin_port = htons(DNS_PORT)};		sockaddr_in sin = {.sin_family = AF_INET, .sin_port = htons(DNS_PORT)};
	ASSERT_TRUE(inet_pton(AF_INET, setup.servers[0].c_str(), &sin.sin_addr));		ASSERT_TRUE(inet_pton(AF_INET, setup.servers[0].c_str(), &sin.sin_addr));
	cacheAddStats(TEST_NETID, 1 /revision_id/, (const sockaddr*)&sin, sample,		cacheAddStats(TEST_NETID, 1 /revision_id/, IPSockAddr(sin), sample, setup.params.max_samples);
	setup.params.max_samples);

	const CacheStats cacheStats = {		const CacheStats cacheStats = {
	.setup = setup,		.setup = setup,