dns: Add support for SRV record parsing and sorting.

This change adds support for parsing SRV records and consuming their values
in an easy fashion. It also adds automatic sorting of SRV records according
to RFC 2782.

Tests have also been included which cover parsing, sorting, and off-nominal
cases where the record is corrupted.

ASTERISK-24931 #close
Reported by: Joshua Colp

Review: https://reviewboard.asterisk.org/r/4528/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@433889 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 74 insertions, 0 deletions

diff --git a/res/res_resolver_unbound.c b/res/res_resolver_unbound.c
index 43f2acdfd..94af28e7f 100644
--- a/res/res_resolver_unbound.c
+++ b/res/res_resolver_unbound.c
@@ -36,6 +36,10 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/config_options.h"
 #include "asterisk/test.h"
 
+#ifdef TEST_FRAMEWORK
+#include "asterisk/dns_srv.h"
+#endif
+
 /*** DOCUMENTATION
 	<configInfo name="res_resolver_unbound" language="en_US">
 		<configFile name="resolver_unbound.conf">
@@ -1181,6 +1185,74 @@ AST_TEST_DEFINE(resolve_cancel_off_nominal)
 
 	return AST_TEST_PASS;
 }
+
+AST_TEST_DEFINE(resolve_srv)
+{
+	RAII_VAR(struct unbound_resolver *, resolver, NULL, ao2_cleanup);
+	RAII_VAR(struct unbound_config *, cfg, NULL, ao2_cleanup);
+	RAII_VAR(struct ast_dns_result *, result, NULL, ast_dns_result_free);
+	const struct ast_dns_record *record;
+	static const char *DOMAIN1 = "taco.bananas";
+	static const char *DOMAIN1_SRV = "taco.bananas 12345 IN SRV 10 20 5060 sip.taco.bananas";
+	enum ast_test_result_state res = AST_TEST_PASS;
+
+	switch (cmd) {
+	case TEST_INIT:
+		info->name = "resolve_srv";
+		info->category = "/res/res_resolver_unbound/";
+		info->summary = "Test synchronous SRV resolution using libunbound\n";
+		info->description = "This test performs the following:\n"
+			"\t* Set one SRV record on one domain\n"
+			"\t* Perform an SRV lookup on the domain\n"
+			"\t* Ensure that the SRV record returned matches the expected value\n";
+		return AST_TEST_NOT_RUN;
+	case TEST_EXECUTE:
+		break;
+	}
+
+	cfg = ao2_global_obj_ref(globals);
+	resolver = ao2_bump(cfg->global->state->resolver);
+
+	ub_ctx_zone_add(resolver->context, DOMAIN1, "static");
+	ub_ctx_data_add(resolver->context, DOMAIN1_SRV);
+
+	if (ast_dns_resolve(DOMAIN1, ns_t_srv, ns_c_in, &result)) {
+		ast_test_status_update(test, "Failed to synchronously resolve SRV for domain '%s'\n", DOMAIN1);
+		res = AST_TEST_FAIL;
+		goto cleanup;
+	}
+
+	record = ast_dns_result_get_records(result);
+	if (ast_dns_srv_get_priority(record) != 10) {
+		ast_test_status_update(test, "SRV Record returned priority '%d' when we expected 10\n", ast_dns_srv_get_priority(record));
+		res = AST_TEST_FAIL;
+		goto cleanup;
+	}
+
+	if (ast_dns_srv_get_weight(record) != 20) {
+		ast_test_status_update(test, "SRV Record returned weight '%d' when we expected 20\n", ast_dns_srv_get_weight(record));
+		res = AST_TEST_FAIL;
+		goto cleanup;
+	}
+
+	if (ast_dns_srv_get_port(record) != 5060) {
+		ast_test_status_update(test, "SRV Record returned port '%d' when we expected 5060\n", ast_dns_srv_get_port(record));
+		res = AST_TEST_FAIL;
+		goto cleanup;
+	}
+
+	if (strcmp(ast_dns_srv_get_host(record), "sip.taco.bananas")) {
+		ast_test_status_update(test, "SRV Record returned host '%s' when we expected sip.taco.bananas\n", ast_dns_srv_get_host(record));
+		res = AST_TEST_FAIL;
+		goto cleanup;
+	}
+
+cleanup:
+	ub_ctx_data_remove(resolver->context, DOMAIN1_SRV);
+	ub_ctx_zone_remove(resolver->context, DOMAIN1);
+
+	return res;
+}
 #endif
 
 static int reload_module(void)
@@ -1202,6 +1274,7 @@ static int unload_module(void)
 	AST_TEST_UNREGISTER(resolve_sync_off_nominal);
 	AST_TEST_UNREGISTER(resolve_sync_off_nominal);
 	AST_TEST_UNREGISTER(resolve_cancel_off_nominal);
+	AST_TEST_UNREGISTER(resolve_srv);
 	return 0;
 }
 
@@ -1258,6 +1331,7 @@ static int load_module(void)
 	AST_TEST_REGISTER(resolve_sync_off_nominal);
 	AST_TEST_REGISTER(resolve_async_off_nominal);
 	AST_TEST_REGISTER(resolve_cancel_off_nominal);
+	AST_TEST_REGISTER(resolve_srv);
 
 	return AST_MODULE_LOAD_SUCCESS;
 }