Moved server to server.h/.c, added tests

- All server functions have been moved to server.h/.c
- main call run_dns_server() or run_test() depending on makefile target
- Makefile target test is now available
- test.h/.c provide unit tests

5 files changed, 302 insertions, 211 deletions

diff --git a/src/main.c b/src/main.c
index ff07c48..f193f44 100644
--- a/src/main.c
+++ b/src/main.c
@@ -5,222 +5,18 @@
 
 #include <stdio.h>
 #include <stdlib.h>
-#include <errno.h>
-#include <string.h>
 #include <sys/types.h>
 
-#include <sys/socket.h>
-#include <netinet/ip.h>
-#include <arpa/inet.h>
-
-#include <unistd.h>
-
-#include <signal.h>
-
-#include "dns.h"
 #include "log.h"
 
-#include "zonefile.h"
-
-#define PRINT_ERRNO() {printf("%s:%i %i:%s\n", __FILE__, __LINE__, errno, strerror(errno));}
-
-#define UDP_BUFFER_LEN 512
-
-//main server socket
-int sock_server;
-
-int handle_connection (	int _socket,
-			struct sockaddr_in *sockaddr_client,
-			socklen_t sockaddr_client_len,
-			char* _buffer,
-			int _bufflen );
-
-void signal_term ( );
-
-void signal_term_child ( );
-
-void signal_child ( );
-
-int main1(	int argc,
-		char* argv[] )
-{
-	printf("TEST MODE. NOT FUNCTIONAL\n");
-
-	printf ("%i\n", string_compare (argv[1], argv[2]));
-
-	return 0;
-	/*
-	//Fuzztest the QNAME checker
-	FILE* urand = fopen ("/dev/urandom", "r");
-	char rand[128];
-	char out[129];
-	out[128] = 0;
-
-	if (!urand)
-		return 1;
-
-	for (;;) {
-		if (fread (rand, 128, 1, urand) > 0) {
-			if ( qname_check(rand, 128) > 0 ) {
-				qname_to_fqdn ( rand, 128, out, 128);
-				printf("Valid %s\n", out);
-			}
-		}
-	}*/
-
-	char in[128];
-	char out[128];
-
-	strncpy ( in, "sub.domain.example.com\0", 127);
-
-	printf("%s\n", in);
-
-	int written = fqdn_to_qname (in,128,out,128);
-
-	if ( qname_check(out,128) < 0)
-		printf("Wrong\n");
-	else
-		printf("qname ok\n");
-
-	if (written < 0) {
-		printf("invallid fqdn\n");
-		return 1;
-	}
-
-	for(int i = 0; i < written; i++)
-		printf(" %x ", out[i]);
-
-	written = qname_to_fqdn (out,128,in,128);
-
-	if (written < 0) {
-		printf("invalid qname\n");
-		return 1;
-	}
-
-	printf("%s\n", in);
-
-	printf("\n\n");
-	return 0;
-}
-
-int main(	int argc,
-		char* argv[] )
+int main(int argc, char* argv[])
 {
-	int		ret;
-	struct		sockaddr_in sock_server_addr;
-
-	char recv_buffer[ UDP_BUFFER_LEN ];
-
-	signal ( SIGTERM, signal_term );
-	signal ( SIGINT,  signal_term );
-
-	//Avoid zombie processes
-	signal (SIGCHLD, SIG_IGN);
-
-	log_init_stdout ( _LOG_DEBUG );
-
-	sock_server = socket ( AF_INET, SOCK_DGRAM, 0 );
-	if ( sock_server == -1 ) {
-		LOGPRINTF(_LOG_ERROR, "socket() failed");
-		return errno;
-	}
-
-	memset( &sock_server_addr, '\0', sizeof(struct sockaddr_in) );
-	sock_server_addr.sin_family = AF_INET;
-	sock_server_addr.sin_port   = htons( 53 );
-	ret = inet_aton ( "0.0.0.0", & sock_server_addr.sin_addr );
-	if( ret == 0 ) { //Error on 0, no errno!
-		LOGPRINTF(_LOG_NOTE, "inet_aton(): Invalid bind IP\n" );
-		return 1;
-	}
-
-	ret = bind (	sock_server,
-			(struct sockaddr*) &sock_server_addr,
-			sizeof(struct sockaddr_in) );
-	if ( ret == -1 ) {
-		LOGPRINTF(_LOG_ERROR, "bind() failed");
-		return errno;
-	}
-
-	while( 1 )
-	{
-		struct 		sockaddr_in sock_client_addr;
-		socklen_t	sock_client_addr_len;
-
-		sock_client_addr_len = sizeof ( struct sockaddr_in );
-		memset ( &sock_client_addr, '\0', sock_client_addr_len );
-
-		ret = recvfrom (sock_server,
-				recv_buffer,
-				UDP_BUFFER_LEN,
-				0,
-				(struct sockaddr*) &sock_client_addr,
-				&sock_client_addr_len );
-		if ( ret == -1 ) {
-			LOGPRINTF( _LOG_ERROR, "recvfrom()");
-			return errno;
-		}
-
-		LOGPRINTF(_LOG_DEBUG, "UDP Packet size %i", ret);
-
-		handle_connection ( sock_server,
-				&sock_client_addr,
-				sock_client_addr_len,
-				recv_buffer,
-				ret );
-	}
-
-	close( sock_server );
-
-	return 0;
-}
-
-int handle_connection (	int _socket,
-			struct sockaddr_in *sockaddr_client,
-			socklen_t sockaddr_client_len,
-			char* _buffer,
-			int _bufflen )
-{
-	struct dns_message msg;
-
-	if (dns_parse_packet (_buffer, _bufflen, &msg) ) {
-		LOGPRINTF (_LOG_DEBUG, "Malformed packet recieved. parsing failed");
-		return 1;
-	}
-
-	if(msg.question_count > 0) {
-		char out[128];
-		qname_to_fqdn( (char*) msg.question[0].qname, 100, out, 128);
-		printf("%s %i\n", out, msg.question[0].qtype);
-	}
-	
-	dns_destroy_struct ( &msg );
-
-	//Always return NXDOMAIN
-	struct dns_header head = {msg.header.id,1,OP_Q,0,0,0,0,0,NAMEERR,0,0,0,0};
-	char ret[20];
-	int retlen = dns_construct_header ( &head, ret, 20 );
-	sendto (_socket, ret, retlen, 0, (struct sockaddr*) sockaddr_client, sockaddr_client_len);
+	//CMD line arg parsing goes in here
+#ifdef _TEST
+	run_test();
+#else
+	run_dns_server();
+#endif
 	
-	return 0;
 }
 
-void signal_term ( ) {
-	printf( "Recieved Signal. Terminating active connections and closing socket\n" );
-
-	//terminate all children >:)
-	kill ( 0, SIGTERM ); 
-
-	shutdown ( sock_server, SHUT_RDWR );
-	close ( sock_server );
-
-	printf( "done\n" );
-
-	exit( 0 );
-}
-
-void signal_term_child ( ) {
-	close ( sock_server );
-	printf ( "%i: Active connection terminated\n", getpid() );
-	exit( 0 );
-}
diff --git a/src/server.c b/src/server.c
new file mode 100644
index 0000000..4ca1985
--- /dev/null
+++ b/src/server.c
@@ -0,0 +1,120 @@
+/* main.c
+ * (c) Jonas Gunz, 2020
+ * License: MIT
+ * */
+
+#include "server.h"
+
+void run_dns_server ( void )
+{
+	int		ret;
+	struct		sockaddr_in sock_server_addr;
+
+	char recv_buffer[ UDP_BUFFER_LEN ];
+
+	signal ( SIGTERM, signal_term );
+	signal ( SIGINT,  signal_term );
+
+	//Avoid zombie processes
+	//TODO currently useless, since no forking is done.
+	signal (SIGCHLD, SIG_IGN);
+
+	log_init_stdout ( _LOG_DEBUG );
+
+	sock_server = socket ( AF_INET, SOCK_DGRAM, 0 );
+	if ( sock_server == -1 ) {
+		LOGPRINTF(_LOG_ERROR, "socket() failed");
+		exit ( errno );
+	}
+
+	memset( &sock_server_addr, '\0', sizeof(struct sockaddr_in) );
+	sock_server_addr.sin_family = AF_INET;
+	sock_server_addr.sin_port   = htons( 53 );
+	ret = inet_aton ( "0.0.0.0", & sock_server_addr.sin_addr );
+	if( ret == 0 ) { //Error on 0, no errno!
+		LOGPRINTF(_LOG_NOTE, "inet_aton(): Invalid bind IP\n" );
+		exit ( 1 );
+	}
+
+	ret = bind (	sock_server,
+			(struct sockaddr*) &sock_server_addr,
+			sizeof(struct sockaddr_in) );
+	if ( ret == -1 ) {
+		LOGPRINTF(_LOG_ERROR, "bind() failed");
+		exit ( errno );
+	}
+
+	while( 1 )
+	{
+		struct 		sockaddr_in sock_client_addr;
+		socklen_t	sock_client_addr_len;
+
+		sock_client_addr_len = sizeof ( struct sockaddr_in );
+		memset ( &sock_client_addr, '\0', sock_client_addr_len );
+
+		ret = recvfrom (sock_server,
+				recv_buffer,
+				UDP_BUFFER_LEN,
+				0,
+				(struct sockaddr*) &sock_client_addr,
+				&sock_client_addr_len );
+		if ( ret == -1 ) {
+			LOGPRINTF( _LOG_ERROR, "recvfrom()");
+			exit ( errno );
+		}
+
+		LOGPRINTF(_LOG_DEBUG, "UDP Packet size %i", ret);
+
+		handle_connection ( sock_server,
+				&sock_client_addr,
+				sock_client_addr_len,
+				recv_buffer,
+				ret );
+	}
+
+	close( sock_server );
+}
+
+int handle_connection (	int _socket,
+			struct sockaddr_in *sockaddr_client,
+			socklen_t sockaddr_client_len,
+			char* _buffer,
+			int _bufflen )
+{
+	struct dns_message msg;
+
+	if (dns_parse_packet (_buffer, _bufflen, &msg) ) {
+		LOGPRINTF (_LOG_DEBUG, "Malformed packet recieved. parsing failed");
+		return 1;
+	}
+
+	if(msg.question_count > 0) {
+		char out[128];
+		qname_to_fqdn( (char*) msg.question[0].qname, 100, out, 128);
+		printf("%s %i\n", out, msg.question[0].qtype);
+	}
+	
+	dns_destroy_struct ( &msg );
+
+	//Always return NXDOMAIN
+	struct dns_header head = {msg.header.id,1,OP_Q,0,0,0,0,0,NAMEERR,0,0,0,0};
+	char ret[20];
+	int retlen = dns_construct_header ( &head, ret, 20 );
+	sendto (_socket, ret, retlen, 0, (struct sockaddr*) sockaddr_client, sockaddr_client_len);
+	
+	return 0;
+}
+
+void signal_term ( ) {
+	printf( "Recieved Signal. Terminating active connections and closing socket\n" );
+
+	//terminate all children >:)
+	kill ( 0, SIGTERM ); 
+
+	shutdown ( sock_server, SHUT_RDWR );
+	close ( sock_server );
+
+	printf( "done\n" );
+
+	exit( 0 );
+}
diff --git a/src/server.h b/src/server.h
new file mode 100644
index 0000000..388dbae
--- /dev/null
+++ b/src/server.h
@@ -0,0 +1,37 @@
+/* server.h
+ * (c) Jonas Gunz, 2020
+ * License: MIT
+ * */
+
+#pragma once
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include <sys/socket.h>
+#include <netinet/ip.h>
+#include <arpa/inet.h>
+
+#include <unistd.h>
+
+#include <signal.h>
+
+#include "dns.h"
+#include "log.h"
+
+#define UDP_BUFFER_LEN 512
+
+static int sock_server;
+
+void run_dns_server ( void );
+
+int handle_connection (	int _socket,
+			struct sockaddr_in *sockaddr_client,
+			socklen_t sockaddr_client_len,
+			char* _buffer,
+			int _bufflen );
+
+void signal_term ( );
diff --git a/src/test.c b/src/test.c
new file mode 100644
index 0000000..d635515
--- /dev/null
+++ b/src/test.c
@@ -0,0 +1,109 @@
+/* test.c
+ * (c) Jonas Gunz, 2020
+ * License: MIT
+ * */
+
+#include "test.h"
+
+#ifdef _TEST
+
+void run_test ()
+{
+	//Space for temporary tests
+	
+	//tree_balanced_insert(NULL, NULL, NULL, 15 );
+	//Normal tests
+	test_tree();
+	test_dns_parsing();
+	test_dns_parsing_fuzz();
+}
+
+int test_tree ()
+{
+	printf("\ntest_tree()\n");
+
+	struct tree_node* root = NULL;
+	
+	tree_insert ( &root, "eins", "Test eins" );
+	tree_insert ( &root, "zwei", "Test zwei" );
+	
+	printf("After Insert\n");
+
+	printf("%s\n", tree_get(&root, "zwei"));
+
+	printf("After Get\n");
+
+	tree_destroy (&root,0);
+
+	printf("After destroy\n");
+
+	return 0;
+}
+
+int test_dns_parsing ()
+{
+	printf("test_dns_parsing()\n");
+	char in[128];
+	char out[128];
+
+	strncpy ( in, "sub.domain.example.com\0", 127);
+
+	printf("%s\n", in);
+
+	int written = fqdn_to_qname (in,128,out,128);
+
+	if ( qname_check(out,128) < 0)
+		printf("Wrong\n");
+	else
+		printf("qname ok\n");
+
+	if (written < 0) {
+		printf("invallid fqdn\n");
+		return 1;
+	}
+
+	for(int i = 0; i < written; i++)
+		printf(" %x ", out[i]);
+
+	written = qname_to_fqdn (out,128,in,128);
+
+	if (written < 0) {
+		printf("invalid qname\n");
+		return 1;
+	}
+
+	printf("%s\n", in);
+
+	printf("\n\n");
+	return 0;
+}
+
+int test_dns_parsing_fuzz()
+{
+	printf("\n-> test_parsing_fuzz()\n======\n\n");
+	FILE* urand = fopen ("/dev/urandom", "r");
+	char rand[128];
+	char out[129];
+	out[128] = 0;
+
+	if (!urand)
+		return 1;
+
+	unsigned long int limit = 10000000;
+	unsigned long int valid_cnt = 0;
+	for (unsigned long int i = 0; i < limit; i++) {
+		if (fread (rand, 128, 1, urand) > 0) {
+			if ( qname_check(rand, 128) > 0 ) {
+				qname_to_fqdn ( rand, 128, out, 128);
+				//printf("Valid %s\n", out);
+				valid_cnt++;
+			}
+		}
+	}
+
+	float valid_percent = (float)valid_cnt / (float)limit * 100;
+	printf("# of valid qnames in random data: %i / %i = %f%%\n", valid_cnt, limit, valid_percent);
+
+	return 0;
+}
+#endif
diff --git a/src/test.h b/src/test.h
new file mode 100644
index 0000000..885e304
--- /dev/null
+++ b/src/test.h
@@ -0,0 +1,29 @@
+/* test.h
+ * (c) Jonas Gunz, 2020
+ * License: MIT
+ * */
+
+#pragma once
+
+#include <stdio.h>
+#include "tree.h"
+#include "dns.h"
+
+/*
+ * TODO
+ * * fuzz dns_parse_packet()
+ * * test dns_parse_packet() with random valid data
+ * * test qname_check() with random valid data
+ */
+
+#ifdef _TEST
+
+void run_test ();
+
+int test_tree ();
+
+int test_dns_parsing ();
+
+int test_dns_parsing_fuzz();
+
+#endif