From ccb47ef3276e4dbdb31267ab2574578cb734925b Mon Sep 17 00:00:00 2001
From: Nick Peng <pymumu@gmail.com>
Date: Wed, 28 Sep 2022 20:28:01 +0800
Subject: [PATCH] conf: fix local domain  handling issues

---
 src/dns_conf.c   | 44 ++++++++++++++++++++++++++++++--------------
 src/dns_server.c | 35 +++++++++++++++++++++--------------
 2 files changed, 51 insertions(+), 28 deletions(-)

diff --git a/src/dns_conf.c b/src/dns_conf.c
index 31d1178..3dc8927 100644
--- a/src/dns_conf.c
+++ b/src/dns_conf.c
@@ -2123,26 +2123,42 @@ static int _config_log_level(void *data, int argc, char *argv[])
 static void _config_setup_smartdns_domain(void)
 {
 	char hostname[DNS_MAX_CNAME_LEN];
-	/* get local host name */
-	if (getdomainname(hostname, DNS_MAX_CNAME_LEN) != 0) {
-		gethostname(hostname, DNS_MAX_CNAME_LEN);
+	char domainname[DNS_MAX_CNAME_LEN];
+
+	hostname[0] = '\0';
+	domainname[0] = '\0';
+
+	/* get local domain name */
+	if (getdomainname(domainname, DNS_MAX_CNAME_LEN - 1) == 0) {
+		/* check domain is valid */
+		if (strncmp(domainname, "(none)", DNS_MAX_CNAME_LEN - 1) == 0) {
+			domainname[0] = '\0';
+		}
 	}
 
-	/* get host name again */
-	if (strncmp(hostname, "(none)", DNS_MAX_CNAME_LEN - 1) == 0) {
-		gethostname(hostname, DNS_MAX_CNAME_LEN);
+	if (gethostname(hostname, DNS_MAX_CNAME_LEN - 1) == 0) {
+		/* check hostname is valid */
+		if (strncmp(hostname, "(none)", DNS_MAX_CNAME_LEN - 1) == 0) {
+			hostname[0] = '\0';
+		}
 	}
 
-	/* if hostname is (none), return smartdns */
-	if (strncmp(hostname, "(none)", DNS_MAX_CNAME_LEN - 1) == 0) {
-		safe_strncpy(hostname, "smartdns", DNS_MAX_CNAME_LEN);
+	if (dns_conf_resolv_hostname == 1) {
+		/* add hostname to rule table */
+		if (hostname[0] != '\0') {
+			_config_domain_rule_flag_set(hostname, DOMAIN_FLAG_SMARTDNS_DOMAIN, 0);
+		}
+
+		/* add domainname to rule table */
+		if (domainname[0] != '\0') {
+			char full_domain[DNS_MAX_CNAME_LEN];
+			snprintf(full_domain, DNS_MAX_CNAME_LEN, "%.64s.%.128s", hostname, domainname);
+			_config_domain_rule_flag_set(full_domain, DOMAIN_FLAG_SMARTDNS_DOMAIN, 0);
+		}
 	}
 
-	if (dns_conf_resolv_hostname == 1 && hostname[0] != '\0') {
-		_config_domain_rule_flag_set(hostname, DOMAIN_FLAG_SMARTDNS_DOMAIN, 0);
-	}
-
-	if (dns_conf_server_name[0] != '\0') {
+	/* add server name to rule table */
+	if (dns_conf_server_name[0] != '\0' && strncmp(dns_conf_server_name, "smartdns", DNS_MAX_CNAME_LEN - 1) != 0) {
 		_config_domain_rule_flag_set(dns_conf_server_name, DOMAIN_FLAG_SMARTDNS_DOMAIN, 0);
 	}
 
diff --git a/src/dns_server.c b/src/dns_server.c
index 8421c4e..aa951b8 100644
--- a/src/dns_server.c
+++ b/src/dns_server.c
@@ -3161,33 +3161,40 @@ static int _dns_server_process_local_ptr(struct dns_request *request)
 		goto errout;
 	}
 
-	char hostname[DNS_MAX_CNAME_LEN];
+	char full_hostname[DNS_MAX_CNAME_LEN];
 	if (dns_conf_server_name[0] == 0) {
-		/* get local host name */
-		if (getdomainname(hostname, DNS_MAX_CNAME_LEN) != 0) {
-			if (gethostname(hostname, DNS_MAX_CNAME_LEN) != 0) {
-				return -1;
+		char hostname[DNS_MAX_CNAME_LEN];
+		char domainname[DNS_MAX_CNAME_LEN];
+
+		/* get local domain name */
+		if (getdomainname(domainname, DNS_MAX_CNAME_LEN - 1) == 0) {
+			/* check domain is valid */
+			if (strncmp(domainname, "(none)", DNS_MAX_CNAME_LEN - 1) == 0) {
+				domainname[0] = '\0';
 			}
 		}
 
-		/* get host name again */
-		if (strncmp(hostname, "(none)", DNS_MAX_CNAME_LEN - 1) == 0) {
-			if (gethostname(hostname, DNS_MAX_CNAME_LEN) != 0) {
-				return -1;
+		if (gethostname(hostname, DNS_MAX_CNAME_LEN - 1) == 0) {
+			/* check hostname is valid */
+			if (strncmp(hostname, "(none)", DNS_MAX_CNAME_LEN - 1) == 0) {
+				hostname[0] = '\0';
 			}
 		}
 
-		/* if hostname is (none), return smartdns */
-		if (strncmp(hostname, "(none)", DNS_MAX_CNAME_LEN - 1) == 0) {
-			safe_strncpy(hostname, "smartdns", DNS_MAX_CNAME_LEN);
+		if (hostname[0] != '\0' && domainname[0] != '\0') {
+			snprintf(full_hostname, sizeof(full_hostname), "%.64s.%.128s", hostname, domainname);
+		} else if (hostname[0] != '\0') {
+			safe_strncpy(full_hostname, hostname, DNS_MAX_CNAME_LEN);
+		} else {
+			safe_strncpy(full_hostname, "smartdns", DNS_MAX_CNAME_LEN);
 		}
 	} else {
 		/* return configured server name */
-		safe_strncpy(hostname, dns_conf_server_name, DNS_MAX_CNAME_LEN);
+		safe_strncpy(full_hostname, dns_conf_server_name, DNS_MAX_CNAME_LEN);
 	}
 
 	request->has_ptr = 1;
-	safe_strncpy(request->ptr_hostname, hostname, DNS_MAX_CNAME_LEN);
+	safe_strncpy(request->ptr_hostname, full_hostname, DNS_MAX_CNAME_LEN);
 
 	freeifaddrs(ifaddr);
 	return 0;