Unify MAXPACKET and refactor buffer allocation of getaddrinfo (49b70b98) · Commits · e / os / android_packages_modules_DnsResolver

DnsProxyListener.cpp

+0 −4

Original line number	Original line	Diff line number	Diff line
	@@ -74,10 +74,6 @@ namespace {
	// Limits the number of outstanding DNS queries by client UID.		// Limits the number of outstanding DNS queries by client UID.
	constexpr int MAX_QUERIES_PER_UID = 256;		constexpr int MAX_QUERIES_PER_UID = 256;

	// Max packet size for answer, sync with getaddrinfo.c
	// TODO: switch to dynamically allocated buffers with std::vector
	constexpr int MAXPACKET = 8 * 1024;

	android::netdutils::OperationLimiter<uid_t> queryLimiter(MAX_QUERIES_PER_UID);		android::netdutils::OperationLimiter<uid_t> queryLimiter(MAX_QUERIES_PER_UID);

	void logArguments(int argc, char** argv) {		void logArguments(int argc, char** argv) {

getaddrinfo.cpp

+20 −44

Original line number	Original line	Diff line number	Diff line
	@@ -108,20 +108,13 @@ const Explore explore_options[] = {
	};		};

	#define PTON_MAX 16		#define PTON_MAX 16
	#define MAXPACKET (8 * 1024)

	typedef union {
	HEADER hdr;
	uint8_t buf[MAXPACKET];
	} querybuf;

	struct res_target {		struct res_target {
	struct res_target* next;		struct res_target* next;
	const char* name; /* domain name */		const char* name; // domain name
	int qclass, qtype; /* class and type of query */		int qclass, qtype; // class and type of query
	uint8_t* answer; /* buffer to put answer */		std::vector<uint8_t> answer = std::vector<uint8_t>(MAXPACKET, 0); // buffer to put answer
	int anslen; /* size of answer buffer */		int n = 0; // result length
	int n; /* result length */
	};		};

	static int str2number(const char*);		static int str2number(const char*);
	@@ -139,8 +132,8 @@ static int get_port(const struct addrinfo, const char, int);
	static const struct afd* find_afd(int);		static const struct afd* find_afd(int);
	static int ip6_str2scopeid(const char, struct sockaddr_in6, uint32_t*);		static int ip6_str2scopeid(const char, struct sockaddr_in6, uint32_t*);

	static struct addrinfo* getanswer(const querybuf, int, const char, int, const struct addrinfo*,		static struct addrinfo* getanswer(const std::vector<uint8_t>&, int, const char*, int,
	int* herrno);		const struct addrinfo, int herrno);
	static int dns_getaddrinfo(const char* name, const addrinfo* pai,		static int dns_getaddrinfo(const char* name, const addrinfo* pai,
	const android_net_context* netcontext, addrinfo** rv,		const android_net_context* netcontext, addrinfo** rv,
	NetworkDnsEventReported* event);		NetworkDnsEventReported* event);
	@@ -838,8 +831,8 @@ static int ip6_str2scopeid(const char* scope, struct sockaddr_in6* sin6, uint32_
	} \		} \
	} while (0)		} while (0)

	static struct addrinfo* getanswer(const querybuf* answer, int anslen, const char* qname, int qtype,		static struct addrinfo* getanswer(const std::vector<uint8_t>& answer, int anslen, const char* qname,
	const struct addrinfo* pai, int* herrno) {		int qtype, const struct addrinfo* pai, int* herrno) {
	struct addrinfo sentinel = {};		struct addrinfo sentinel = {};
	struct addrinfo *cur;		struct addrinfo *cur;
	struct addrinfo ai;		struct addrinfo ai;
	@@ -856,14 +849,13 @@ static struct addrinfo* getanswer(const querybuf* answer, int anslen, const char
	int (name_ok)(const char);		int (name_ok)(const char);
	char hostbuf[8 * 1024];		char hostbuf[8 * 1024];

	assert(answer != NULL);
	assert(qname != NULL);		assert(qname != NULL);
	assert(pai != NULL);		assert(pai != NULL);

	cur = &sentinel;		cur = &sentinel;

	canonname = NULL;		canonname = NULL;
	eom = answer->buf + anslen;		eom = answer.data() + anslen;
	switch (qtype) {		switch (qtype) {
	case T_A:		case T_A:
	case T_AAAA:		case T_AAAA:
	@@ -876,18 +868,18 @@ static struct addrinfo* getanswer(const querybuf* answer, int anslen, const char
	/*		/*
	* find first satisfactory answer		* find first satisfactory answer
	*/		*/
	hp = &answer->hdr;		hp = reinterpret_cast<const HEADER*>(answer.data());
	ancount = ntohs(hp->ancount);		ancount = ntohs(hp->ancount);
	qdcount = ntohs(hp->qdcount);		qdcount = ntohs(hp->qdcount);
	bp = hostbuf;		bp = hostbuf;
	ep = hostbuf + sizeof hostbuf;		ep = hostbuf + sizeof hostbuf;
	cp = answer->buf;		cp = answer.data();
	BOUNDED_INCR(HFIXEDSZ);		BOUNDED_INCR(HFIXEDSZ);
	if (qdcount != 1) {		if (qdcount != 1) {
	*herrno = NO_RECOVERY;		*herrno = NO_RECOVERY;
	return (NULL);		return (NULL);
	}		}
	n = dn_expand(answer->buf, eom, cp, bp, ep - bp);		n = dn_expand(answer.data(), eom, cp, bp, ep - bp);
	if ((n < 0) \|\| !(*name_ok)(bp)) {		if ((n < 0) \|\| !(*name_ok)(bp)) {
	*herrno = NO_RECOVERY;		*herrno = NO_RECOVERY;
	return (NULL);		return (NULL);
	@@ -911,7 +903,7 @@ static struct addrinfo* getanswer(const querybuf* answer, int anslen, const char
	haveanswer = 0;		haveanswer = 0;
	had_error = 0;		had_error = 0;
	while (ancount-- > 0 && cp < eom && !had_error) {		while (ancount-- > 0 && cp < eom && !had_error) {
	n = dn_expand(answer->buf, eom, cp, bp, ep - bp);		n = dn_expand(answer.data(), eom, cp, bp, ep - bp);
	if ((n < 0) \|\| !(*name_ok)(bp)) {		if ((n < 0) \|\| !(*name_ok)(bp)) {
	had_error++;		had_error++;
	continue;		continue;
	@@ -931,7 +923,7 @@ static struct addrinfo* getanswer(const querybuf* answer, int anslen, const char
	continue; /* XXX - had_error++ ? */		continue; /* XXX - had_error++ ? */
	}		}
	if ((qtype == T_A \|\| qtype == T_AAAA \|\| qtype == T_ANY) && type == T_CNAME) {		if ((qtype == T_A \|\| qtype == T_AAAA \|\| qtype == T_ANY) && type == T_CNAME) {
	n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);		n = dn_expand(answer.data(), eom, cp, tbuf, sizeof tbuf);
	if ((n < 0) \|\| !(*name_ok)(tbuf)) {		if ((n < 0) \|\| !(*name_ok)(tbuf)) {
	had_error++;		had_error++;
	continue;		continue;
	@@ -1397,16 +1389,11 @@ static int dns_getaddrinfo(const char* name, const addrinfo* pai,
	res_target q = {};		res_target q = {};
	res_target q2 = {};		res_target q2 = {};

	auto buf = std::make_unique<querybuf>();
	auto buf2 = std::make_unique<querybuf>();

	switch (pai->ai_family) {		switch (pai->ai_family) {
	case AF_UNSPEC: {		case AF_UNSPEC: {
	/* prefer IPv6 */		/* prefer IPv6 */
	q.name = name;		q.name = name;
	q.qclass = C_IN;		q.qclass = C_IN;
	q.answer = buf->buf;
	q.anslen = sizeof(buf->buf);
	int query_ipv6 = 1, query_ipv4 = 1;		int query_ipv6 = 1, query_ipv4 = 1;
	if (pai->ai_flags & AI_ADDRCONFIG) {		if (pai->ai_flags & AI_ADDRCONFIG) {
	query_ipv6 = have_ipv6(netcontext->app_mark, netcontext->uid);		query_ipv6 = have_ipv6(netcontext->app_mark, netcontext->uid);
	@@ -1419,8 +1406,6 @@ static int dns_getaddrinfo(const char* name, const addrinfo* pai,
	q2.name = name;		q2.name = name;
	q2.qclass = C_IN;		q2.qclass = C_IN;
	q2.qtype = T_A;		q2.qtype = T_A;
	q2.answer = buf2->buf;
	q2.anslen = sizeof(buf2->buf);
	}		}
	} else if (query_ipv4) {		} else if (query_ipv4) {
	q.qtype = T_A;		q.qtype = T_A;
	@@ -1433,15 +1418,11 @@ static int dns_getaddrinfo(const char* name, const addrinfo* pai,
	q.name = name;		q.name = name;
	q.qclass = C_IN;		q.qclass = C_IN;
	q.qtype = T_A;		q.qtype = T_A;
	q.answer = buf->buf;
	q.anslen = sizeof(buf->buf);
	break;		break;
	case AF_INET6:		case AF_INET6:
	q.name = name;		q.name = name;
	q.qclass = C_IN;		q.qclass = C_IN;
	q.qtype = T_AAAA;		q.qtype = T_AAAA;
	q.answer = buf->buf;
	q.anslen = sizeof(buf->buf);
	break;		break;
	default:		default:
	return EAI_FAMILY;		return EAI_FAMILY;
	@@ -1460,13 +1441,13 @@ static int dns_getaddrinfo(const char* name, const addrinfo* pai,

	addrinfo sentinel = {};		addrinfo sentinel = {};
	addrinfo* cur = &sentinel;		addrinfo* cur = &sentinel;
	addrinfo* ai = getanswer(buf.get(), q.n, q.name, q.qtype, pai, &he);		addrinfo* ai = getanswer(q.answer, q.n, q.name, q.qtype, pai, &he);
	if (ai) {		if (ai) {
	cur->ai_next = ai;		cur->ai_next = ai;
	while (cur && cur->ai_next) cur = cur->ai_next;		while (cur && cur->ai_next) cur = cur->ai_next;
	}		}
	if (q.next) {		if (q.next) {
	ai = getanswer(buf2.get(), q2.n, q2.name, q2.qtype, pai, &he);		ai = getanswer(q2.answer, q2.n, q2.name, q2.qtype, pai, &he);
	if (ai) cur->ai_next = ai;		if (ai) cur->ai_next = ai;
	}		}
	if (sentinel.ai_next == NULL) {		if (sentinel.ai_next == NULL) {
	@@ -1578,7 +1559,6 @@ static bool files_getaddrinfo(const char* name, const addrinfo* pai, addrinfo**
	*/		*/
	static int res_queryN(const char* name, res_target* target, res_state res, int* herrno) {		static int res_queryN(const char* name, res_target* target, res_state res, int* herrno) {
	uint8_t buf[MAXPACKET];		uint8_t buf[MAXPACKET];
	HEADER* hp;
	int n;		int n;
	struct res_target* t;		struct res_target* t;
	int rcode;		int rcode;
	@@ -1591,10 +1571,7 @@ static int res_queryN(const char* name, res_target* target, res_state res, int*
	ancount = 0;		ancount = 0;

	for (t = target; t; t = t->next) {		for (t = target; t; t = t->next) {
	uint8_t* answer;		HEADER* hp = (HEADER)(void)t->answer.data();
	int anslen;

	hp = (HEADER) (void) t->answer;
	bool retried = false;		bool retried = false;
	again:		again:
	hp->rcode = NOERROR; /* default */		hp->rcode = NOERROR; /* default */
	@@ -1602,8 +1579,7 @@ static int res_queryN(const char* name, res_target* target, res_state res, int*
	/* make it easier... */		/* make it easier... */
	int cl = t->qclass;		int cl = t->qclass;
	int type = t->qtype;		int type = t->qtype;
	answer = t->answer;		const int anslen = t->answer.size();
	anslen = t->anslen;

	LOG(DEBUG) << __func__ << ": (" << cl << ", " << type << ")";		LOG(DEBUG) << __func__ << ": (" << cl << ", " << type << ")";

	@@ -1620,7 +1596,7 @@ static int res_queryN(const char* name, res_target* target, res_state res, int*
	return n;		return n;
	}		}

	n = res_nsend(res, buf, n, answer, anslen, &rcode, 0);		n = res_nsend(res, buf, n, t->answer.data(), anslen, &rcode, 0);
	if (n < 0 \|\| hp->rcode != NOERROR \|\| ntohs(hp->ancount) == 0) {		if (n < 0 \|\| hp->rcode != NOERROR \|\| ntohs(hp->ancount) == 0) {
	// Record rcode from DNS response header only if no timeout.		// Record rcode from DNS response header only if no timeout.
	// Keep rcode timeout for reporting later if any.		// Keep rcode timeout for reporting later if any.
	@@ -1689,7 +1665,7 @@ static int res_searchN(const char* name, res_target* target, res_state res, int*
	assert(name != NULL);		assert(name != NULL);
	assert(target != NULL);		assert(target != NULL);

	hp = (HEADER) (void) target->answer; /XXX/		hp = (HEADER)(void)target->answer.data();

	errno = 0;		errno = 0;
	herrno = HOST_NOT_FOUND; / default, if we never query */		herrno = HOST_NOT_FOUND; / default, if we never query */

gethnamaddr.cpp

+0 −2

Original line number	Original line	Diff line number	Diff line
	@@ -95,8 +95,6 @@ using android::net::NetworkDnsEventReported;
	#define maybe_hnok(res, hn) maybe_ok((res), (hn), res_hnok)		#define maybe_hnok(res, hn) maybe_ok((res), (hn), res_hnok)
	#define maybe_dnok(res, dn) maybe_ok((res), (dn), res_dnok)		#define maybe_dnok(res, dn) maybe_ok((res), (dn), res_dnok)

	#define MAXPACKET (8 * 1024)

	constexpr int MAXADDRS = 35;		constexpr int MAXADDRS = 35;

	typedef union {		typedef union {

res_query.cpp

+0 −6

Original line number	Original line	Diff line number	Diff line
	@@ -89,12 +89,6 @@
	#include "resolv_cache.h"		#include "resolv_cache.h"
	#include "resolv_private.h"		#include "resolv_private.h"

	#if PACKETSZ > 1024
	#define MAXPACKET PACKETSZ
	#else
	#define MAXPACKET 1024
	#endif

	/*		/*
	* Formulate a normal query, send, and await answer.		* Formulate a normal query, send, and await answer.
	* Returned answer is placed in supplied buffer "answer".		* Returned answer is placed in supplied buffer "answer".

res_send.cpp

+10 −16

Original line number	Original line	Diff line number	Diff line
	@@ -226,15 +226,6 @@ static struct timespec evNowTime(void) {
	return tsnow;		return tsnow;
	}		}

	static struct iovec evConsIovec(void* buf, size_t cnt) {
	struct iovec ret;

	memset(&ret, 0xf5, sizeof ret);
	ret.iov_base = buf;
	ret.iov_len = cnt;
	return ret;
	}

	// END: Code copied from ISC eventlib		// END: Code copied from ISC eventlib

	/* BIONIC-BEGIN: implement source port randomization */		/* BIONIC-BEGIN: implement source port randomization */
	@@ -669,7 +660,6 @@ static int send_vc(res_state statp, res_params* params, const uint8_t* buf, int
	struct sockaddr* nsap;		struct sockaddr* nsap;
	int nsaplen;		int nsaplen;
	int truncating, connreset, n;		int truncating, connreset, n;
	struct iovec iov[2];
	uint8_t* cp;		uint8_t* cp;

	LOG(INFO) << __func__ << ": using send_vc";		LOG(INFO) << __func__ << ": using send_vc";
	@@ -754,8 +744,10 @@ same_ns:
	* Send length & message		* Send length & message
	*/		*/
	uint16_t len = htons(static_cast<uint16_t>(buflen));		uint16_t len = htons(static_cast<uint16_t>(buflen));
	iov[0] = evConsIovec(&len, INT16SZ);		const iovec iov[] = {
	iov[1] = evConsIovec((void*) buf, (size_t) buflen);		{.iov_base = &len, .iov_len = INT16SZ},
			{.iov_base = const_cast<uint8_t*>(buf), .iov_len = static_cast<size_t>(buflen)},
			};
	if (writev(statp->_vcsock, iov, 2) != (INT16SZ + buflen)) {		if (writev(statp->_vcsock, iov, 2) != (INT16SZ + buflen)) {
	*terrno = errno;		*terrno = errno;
	PLOG(DEBUG) << __func__ << ": write failed: ";		PLOG(DEBUG) << __func__ << ": write failed: ";
	@@ -863,8 +855,8 @@ read_len:
	}		}

	/* return -1 on error (errno set), 0 on success */		/* return -1 on error (errno set), 0 on success */
	static int connect_with_timeout(int sock, const struct sockaddr* nsap, socklen_t salen,		static int connect_with_timeout(int sock, const sockaddr* nsap, socklen_t salen,
	const struct timespec timeout) {		const timespec timeout) {
	int res, origflags;		int res, origflags;

	origflags = fcntl(sock, F_GETFL, 0);		origflags = fcntl(sock, F_GETFL, 0);
	@@ -876,8 +868,8 @@ static int connect_with_timeout(int sock, const struct sockaddr* nsap, socklen_t
	goto done;		goto done;
	}		}
	if (res != 0) {		if (res != 0) {
	struct timespec now = evNowTime();		timespec now = evNowTime();
	struct timespec finish = evAddTime(now, timeout);		timespec finish = evAddTime(now, timeout);
	LOG(INFO) << __func__ << ": " << sock << " send_vc";		LOG(INFO) << __func__ << ": " << sock << " send_vc";
	res = retrying_poll(sock, POLLIN \| POLLOUT, &finish);		res = retrying_poll(sock, POLLIN \| POLLOUT, &finish);
	if (res <= 0) {		if (res <= 0) {
	@@ -1102,6 +1094,7 @@ static void dump_error(const char* str, const struct sockaddr* address, int alen
	char hbuf[NI_MAXHOST];		char hbuf[NI_MAXHOST];
	char sbuf[NI_MAXSERV];		char sbuf[NI_MAXSERV];
	constexpr int niflags = NI_NUMERICHOST \| NI_NUMERICSERV;		constexpr int niflags = NI_NUMERICHOST \| NI_NUMERICSERV;
			const int err = errno;

	if (!WOULD_LOG(DEBUG)) return;		if (!WOULD_LOG(DEBUG)) return;

	@@ -1111,6 +1104,7 @@ static void dump_error(const char* str, const struct sockaddr* address, int alen
	strncpy(sbuf, "?", sizeof(sbuf) - 1);		strncpy(sbuf, "?", sizeof(sbuf) - 1);
	sbuf[sizeof(sbuf) - 1] = '\0';		sbuf[sizeof(sbuf) - 1] = '\0';
	}		}
			errno = err;
	PLOG(DEBUG) << __func__ << ": " << str << " ([" << hbuf << "]." << sbuf << "): ";		PLOG(DEBUG) << __func__ << ": " << str << " ([" << hbuf << "]." << sbuf << "): ";
	}		}