evdns: Add additional validation for values of dns options

(cherry picked from commit 8fe35c7)

Author: ayuseleznev

evdns.c

@@ -3531,6 +3531,7 @@ evdns_base_set_option_impl(struct evdns_base *base,
 		base->global_max_retransmits = retries;
 	} else if (str_matches_option(option, "randomize-case:")) {
 		int randcase = strtoint(val);
+		if (randcase == -1) return -1;
 		if (!(flags & DNS_OPTION_MISC)) return 0;
 		base->global_randomize_case = randcase;
 	} else if (str_matches_option(option, "bind-to:")) {
@@ -3554,11 +3555,13 @@ evdns_base_set_option_impl(struct evdns_base *base,
 		    sizeof(tv));
 	} else if (str_matches_option(option, "so-rcvbuf:")) {
 		int buf = strtoint(val);
+		if (buf == -1) return -1;
 		if (!(flags & DNS_OPTION_MISC)) return 0;
 		log(EVDNS_LOG_DEBUG, "Setting SO_RCVBUF to %s", val);
 		base->so_rcvbuf = buf;
 	} else if (str_matches_option(option, "so-sndbuf:")) {
 		int buf = strtoint(val);
+		if (buf == -1) return -1;
 		if (!(flags & DNS_OPTION_MISC)) return 0;
 		log(EVDNS_LOG_DEBUG, "Setting SO_SNDBUF to %s", val);
 		base->so_sndbuf = buf;

test/regress_dns.c

@@ -2362,6 +2362,71 @@ test_set_so_rcvbuf_so_sndbuf(void *arg)
 		evdns_base_free(dns_base, 0);
 }
 
+static void
+test_set_option(void *arg)
+{
+#define SUCCESS 0
+#define FAIL -1
+	struct basic_test_data *data = arg;
+	struct evdns_base *dns_base;
+	size_t i;
+	/* Option names are allowed to have ':' at the end.
+	 * So all test option names come in pairs.
+	 */
+	const char *int_options[] = {
+		"ndots", "ndots:",
+		"max-timeouts", "max-timeouts:",
+		"max-inflight", "max-inflight:",
+		"attempts", "attempts:",
+		"randomize-case", "randomize-case:",
+		"so-rcvbuf", "so-rcvbuf:",
+		"so-sndbuf", "so-sndbuf:",
+	};
+	const char *timeval_options[] = {
+		"timeout", "timeout:",
+		"getaddrinfo-allow-skew", "getaddrinfo-allow-skew:",
+		"initial-probe-timeout", "initial-probe-timeout:",
+	};
+	const char *addr_port_options[] = {
+		"bind-to", "bind-to:",
+	};
+
+	dns_base = evdns_base_new(data->base, 0);
+	tt_assert(dns_base);
+
+	for (i = 0; i < ARRAY_SIZE(int_options); ++i) {
+		tt_assert(SUCCESS == evdns_base_set_option(dns_base, int_options[i], "0"));
+		tt_assert(SUCCESS == evdns_base_set_option(dns_base, int_options[i], "1"));
+		tt_assert(SUCCESS == evdns_base_set_option(dns_base, int_options[i], "10000"));
+		tt_assert(FAIL == evdns_base_set_option(dns_base, int_options[i], "foo"));
+		tt_assert(FAIL == evdns_base_set_option(dns_base, int_options[i], "3.14"));
+	}
+
+	for (i = 0; i < ARRAY_SIZE(timeval_options); ++i) {
+		tt_assert(SUCCESS == evdns_base_set_option(dns_base, timeval_options[i], "1"));
+		tt_assert(SUCCESS == evdns_base_set_option(dns_base, timeval_options[i], "0.001"));
+		tt_assert(SUCCESS == evdns_base_set_option(dns_base, timeval_options[i], "3.14"));
+		tt_assert(SUCCESS == evdns_base_set_option(dns_base, timeval_options[i], "10000"));
+		tt_assert(FAIL == evdns_base_set_option(dns_base, timeval_options[i], "0"));
+		tt_assert(FAIL == evdns_base_set_option(dns_base, timeval_options[i], "foo"));
+	}
+
+	for (i = 0; i < ARRAY_SIZE(addr_port_options); ++i) {
+		tt_assert(SUCCESS == evdns_base_set_option(dns_base, addr_port_options[i], "8.8.8.8:80"));
+		tt_assert(SUCCESS == evdns_base_set_option(dns_base, addr_port_options[i], "1.2.3.4"));
+		tt_assert(SUCCESS == evdns_base_set_option(dns_base, addr_port_options[i], "::1:82"));
+		tt_assert(SUCCESS == evdns_base_set_option(dns_base, addr_port_options[i], "3::4"));
+		tt_assert(FAIL == evdns_base_set_option(dns_base, addr_port_options[i], "3.14"));
+		tt_assert(FAIL == evdns_base_set_option(dns_base, addr_port_options[i], "foo"));
+	}
+
+#undef SUCCESS
+#undef FAIL
+end:
+	if (dns_base)
+		evdns_base_free(dns_base, 0);
+}
+
 #define DNS_LEGACY(name, flags)					       \
 	{ #name, run_legacy_test_fn, flags|TT_LEGACY, &legacy_setup,   \
 		    dns_##name }
@@ -2435,6 +2500,8 @@ struct testcase_t dns_testcases[] = {
 
 	{ "set_SO_RCVBUF_SO_SNDBUF", test_set_so_rcvbuf_so_sndbuf,
 	  TT_FORK|TT_NEED_BASE, &basic_setup, NULL },
+	{ "set_options", test_set_option,
+	  TT_FORK|TT_NEED_BASE, &basic_setup, NULL },
 
 	END_OF_TESTCASES
 };