Dead code removal - remove res->options (d8cbb9b1) · Commits · e / os / android_packages_modules_DnsResolver

DnsProxyListener.cpp

+1 −1

Original line number	Diff line number	Diff line
		@@ -164,7 +164,7 @@ void maybeFixupNetContext(android_net_context* ctx) {
		// DNS-over-TLS is in use as an indicator for when to use more modern
		// DNS resolution mechanics.
		if (queryingViaTls(ctx->dns_netid)) {
		ctx->flags \|= NET_CONTEXT_FLAG_USE_EDNS;
		ctx->flags \|= NET_CONTEXT_FLAG_USE_DNS_OVER_TLS \| NET_CONTEXT_FLAG_USE_EDNS;
		}
		}
		}

getaddrinfo.cpp

+10 −4

Original line number	Diff line number	Diff line
		@@ -1614,7 +1614,10 @@ static int res_queryN(const char* name, res_target* target, res_state res, int*
		LOG(DEBUG) << __func__ << ": (" << cl << ", " << type << ")";

		n = res_nmkquery(res, QUERY, name, cl, type, NULL, 0, NULL, buf, sizeof(buf));
		if (n > 0 && (res->options & (RES_USE_EDNS0 \| RES_USE_DNSSEC)) != 0 && !retried)
		if (n > 0 &&
		(res->netcontext_flags &
		(NET_CONTEXT_FLAG_USE_DNS_OVER_TLS \| NET_CONTEXT_FLAG_USE_EDNS)) &&
		!retried) // TODO: remove the retry flag and provide a sufficient test coverage.
		n = res_nopt(res, n, buf, sizeof(buf), anslen);
		if (n <= 0) {
		LOG(ERROR) << __func__ << ": res_nmkquery failed";
		@@ -1626,9 +1629,12 @@ static int res_queryN(const char* name, res_target* target, res_state res, int*
		if (n < 0 \|\| hp->rcode != NOERROR \|\| ntohs(hp->ancount) == 0) {
		// Record rcode from DNS response header only if no timeout.
		// Keep rcode timeout for reporting later if any.
		if (rcode != RCODE_TIMEOUT) rcode = hp->rcode; /* record most recent error */
		/* if the query choked with EDNS0, retry without EDNS0 */
		if ((res->options & (RES_USE_EDNS0 \| RES_USE_DNSSEC)) != 0 &&
		if (rcode != RCODE_TIMEOUT) rcode = hp->rcode; // record most recent error
		// if the query choked with EDNS0, retry without EDNS0 that when the server
		// has no response, resovler won't retry and do nothing. Even fallback to UDP,
		// we also has the same symptom if EDNS is enabled.
		if ((res->netcontext_flags &
		(NET_CONTEXT_FLAG_USE_DNS_OVER_TLS \| NET_CONTEXT_FLAG_USE_EDNS)) &&
		(res->_flags & RES_F_EDNS0ERR) && !retried) {
		LOG(DEBUG) << __func__ << ": retry without EDNS0";
		retried = true;

include/netd_resolv/resolv.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -73,6 +73,7 @@ struct android_net_context {
		#define NET_CONTEXT_INVALID_UID ((uid_t) -1)
		#define NET_CONTEXT_FLAG_USE_LOCAL_NAMESERVERS 0x00000001
		#define NET_CONTEXT_FLAG_USE_EDNS 0x00000002
		#define NET_CONTEXT_FLAG_USE_DNS_OVER_TLS 0x00000004

		// TODO: investigate having the resolver check permissions itself, either by adding support to
		// libbinder_ndk or by converting IPermissionController into a stable AIDL interface.

res_init.cpp

+11 −49

Original line number	Diff line number	Diff line
		@@ -94,48 +94,17 @@
		#include "res_state_ext.h"
		#include "resolv_private.h"

		/*
		* Resolver state default settings.
		*/

		/*
		* Set up default settings. If the configuration file exist, the values
		* there will have precedence. Otherwise, the server address is set to
		* INADDR_ANY and the default domain name comes from the gethostname().
		*
		* An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
		* rather than INADDR_ANY ("0.0.0.0") as the default name server address
		* since it was noted that INADDR_ANY actually meant ``the first interface
		* you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
		* it had to be "up" in order for you to reach your own name server. It
		* was later decided that since the recommended practice is to always
		* install local static routes through 127.0.0.1 for all your network
		* interfaces, that we could solve this problem without a code change.
		*
		* The configuration file should always be used, since it is the only way
		* to specify a default domain. If you are running a server on your local
		* machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
		* in the configuration file.
		*
		* Return 0 if completes successfully, -1 on error
		*/
		// Set up Resolver state default settings.
		// Note that res_ninit() is called with an initialized res_state,
		// the memories it allocated must be freed after the task is done.
		// Or memory leak will happen.
		int res_ninit(res_state statp) {
		return res_vinit(statp, 0);
		}

		/* This function has to be reachable by res_data.c but not publicly. */
		int res_vinit(res_state statp, int preinit) {
		int nserv = 0; /* number of nameserver records read from file */
		int nserv = 0; // number of nameserver records
		sockaddr_union u[2];

		if ((statp->options & RES_INIT) != 0U) res_ndestroy(statp);

		if (!preinit) {
		statp->netid = NETID_UNSET;
		statp->options = RES_DEFAULT;
		statp->id = arc4random_uniform(65536);
		statp->_mark = MARK_UNSET;
		}

		memset(u, 0, sizeof(u));
		u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
		@@ -148,7 +117,7 @@ int res_vinit(res_state statp, int preinit) {
		statp->_flags = 0;
		statp->_u._ext.nscount = 0;
		statp->_u._ext.ext = (res_state_ext) malloc(sizeof(statp->_u._ext.ext));
		statp->use_local_nameserver = false;
		statp->netcontext_flags = 0;
		if (statp->_u._ext.ext != NULL) {
		memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
		statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
		@@ -160,7 +129,6 @@ int res_vinit(res_state statp, int preinit) {

		if (nserv > 0) {
		statp->nscount = nserv;
		statp->options \|= RES_INIT;
		}
		return (0);
		}
		@@ -192,7 +160,6 @@ void res_nclose(res_state statp) {
		void res_ndestroy(res_state statp) {
		res_nclose(statp);
		if (statp->_u._ext.ext != NULL) free(statp->_u._ext.ext);
		statp->options &= ~RES_INIT;
		statp->_u._ext.ext = NULL;
		}

		@@ -282,16 +249,11 @@ int res_getservers(res_state statp, sockaddr_union* set, int cnt) {

		void res_setnetcontext(res_state statp, const struct android_net_context* netcontext,
		android::net::NetworkDnsEventReported* _Nonnull event) {
		if (statp != NULL) {
		if (statp != nullptr) {
		statp->netid = netcontext->dns_netid;
		statp->uid = netcontext->uid;
		statp->_mark = netcontext->dns_mark;
		if (netcontext->flags & NET_CONTEXT_FLAG_USE_EDNS) {
		statp->options \|= RES_USE_EDNS0 \| RES_USE_DNSSEC;
		}
		if (netcontext->flags & NET_CONTEXT_FLAG_USE_LOCAL_NAMESERVERS) {
		statp->use_local_nameserver = true;
		}
		statp->netcontext_flags = netcontext->flags;
		statp->event = event;
		}
		}

res_mkquery.cpp

+2 −2

Original line number	Diff line number	Diff line
		@@ -124,7 +124,7 @@ int res_nmkquery(res_state statp, int op, /* opcode of query */
		hp->id = htons(arc4random_uniform(65536));
		hp->opcode = op;
		hp->rd = true;
		hp->ad = (statp->options & RES_USE_DNSSEC) != 0U;
		hp->ad = (statp->netcontext_flags & NET_CONTEXT_FLAG_USE_DNS_OVER_TLS) != 0U;
		hp->rcode = NOERROR;
		cp = buf + HFIXEDSZ;
		ep = buf + buflen;
		@@ -220,7 +220,7 @@ int res_nopt(res_state statp, int n0, /* current offset in buffer */
		cp += INT16SZ;
		cp++ = NOERROR; / extended RCODE */
		cp++ = 0; / EDNS version */
		if (statp->options & RES_USE_DNSSEC) {
		if (statp->netcontext_flags & NET_CONTEXT_FLAG_USE_DNS_OVER_TLS) {
		LOG(DEBUG) << __func__ << ": ENDS0 DNSSEC";
		flags \|= NS_OPT_DNSSEC_OK;
		}