Fix a parsing bug in the rules that would ignore the very first rule. See #23.

- Add an error message when the configuration file could not be found.
 - Log to stderr when running in the foreground.

CHANGES.md

@@ -1,20 +1,29 @@
-## Version 0.71
+## Version 0.73 (2021/02/19)
+
+ * improve error reporting
+ * fixed another configuration parsing bug
+
+## Version 0.72 (2021/02/16)
+
+ * fixed a configuration parsing bug making 0.71 almost unusable
+
+## Version 0.71 (2021/02/14)
 
  * IPv6 support
- * fix a display overflow in data usage statistics
+ * fixed a display overflow in data usage statistics
  * made the configuration parser more tolerant with service names that contain
    dashes (e.g. snmp-trap) or hostnames with underscores (e.g. \_http.example.com).
  * create the log file if it does not exist
  * new Visual Studio project file
 
-## Version 0.70
+## Version 0.70 (2017/09/09)
 
  * UDP support
  * source address binding support
  * use a real grammar for the configuration file and get rid of the hand-made
    parser
 
-## Version 0.63
+## Version 0.63 (2017/07/19)
 
  * added a `-f` flag to run in the foreground
  * quit cleanly when `SIGINT` is received

configure.ac

@@ -1,6 +1,6 @@
 # Process this file with autoconf to produce a configure script.
 AC_PREREQ(2.52)
-AC_INIT(rinetd, 0.71, sam@hocevar.net)
+AC_INIT(rinetd, 0.73, sam@hocevar.net)
 AC_CONFIG_AUX_DIR(.auto)
 AC_CONFIG_SRCDIR([src/rinetd.c])
 AC_CONFIG_HEADER([src/config.h])

rinetd.8

@@ -1,4 +1,4 @@
-.TH rinetd 8 "2021-02-14" "rinetd 0.71"
+.TH rinetd 8 "2021-02-19" "rinetd 0.73"
 
 .SH NAME
 rinetd \- internet redirection server

rinetd.vcxproj

@@ -78,7 +78,7 @@
       <SDLCheck>true</SDLCheck>
       <CompileAs>CompileAsC</CompileAs>
       <ConformanceMode>true</ConformanceMode>
-      <PreprocessorDefinitions>_CONSOLE;PACKAGE_VERSION="0.71";_CRT_SECURE_NO_WARNINGS;_CRT_NONSTDC_NO_DEPRECATE;_WINSOCK_DEPRECATED_NO_WARNINGS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_CONSOLE;PACKAGE_VERSION="0.73";_CRT_SECURE_NO_WARNINGS;_CRT_NONSTDC_NO_DEPRECATE;_WINSOCK_DEPRECATED_NO_WARNINGS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
     </ClCompile>
     <Link>
       <SubSystem>Console</SubSystem>

src/Makefile.am

@@ -15,9 +15,10 @@ parse.c: parse.peg
 	if which leg >/dev/null 2>&1; then leg -o $@ $^; else touch $@; fi
 
 # _POSIX_C_SOURCE is for SA_RESTART and others
+# _DARWIN_C_SOURCE is for NI_MAXHOST on OS X
 # _XOPEN_SOURCE is for struct sigaction
 # _GNU_SOURCE is for h_errno and gethostbyname-related macros
-___rinetd_CFLAGS = -std=c99 \
-                   -D_XOPEN_SOURCE -D_GNU_SOURCE -D_POSIX_C_SOURCE=200809L \
+___rinetd_CFLAGS = -std=c99 -D_POSIX_C_SOURCE=200809L \
+                   -D_XOPEN_SOURCE -D_GNU_SOURCE -D_DARWIN_C_SOURCE \
                    -Wall -Wextra -Wwrite-strings
 

src/net.c

@@ -10,6 +10,7 @@
 #	include <config.h>
 #endif
 
+#include <stdio.h>
 #include "net.h"
 
 void setSocketDefaults(SOCKET fd) {
@@ -32,13 +33,23 @@ void setSocketDefaults(SOCKET fd) {
 #endif
 }
 
-struct addrinfo getAddrInfoHint(int protocol) {
-	return (struct addrinfo) {
+int getAddrInfoWithProto(char *address, char *port, int protocol, struct addrinfo **ai)
+{
+	struct addrinfo hints = {
 		.ai_family = AF_UNSPEC,
 		.ai_protocol = protocol,
 		.ai_socktype = protocol == IPPROTO_UDP ? SOCK_DGRAM : SOCK_STREAM,
 		.ai_flags = AI_PASSIVE,
 	};
+
+	int ret = getaddrinfo(address, port, &hints, ai);
+	if (ret != 0) {
+		fprintf(stderr, "rinetd: cannot resolve host \"%s\" port %s "
+				"(getaddrinfo() error: %s)\n",
+			address, port ? port : "<null>", gai_strerror(ret));
+	}
+
+	return ret;
 }
 
 int sameSocketAddress(struct sockaddr_storage *a, struct sockaddr_storage *b) {

src/net.h

@@ -85,6 +85,6 @@ static inline int GetLastError(void) {
 #endif /* _WIN32 */
 
 void setSocketDefaults(SOCKET fd);
-struct addrinfo getAddrInfoHint(int protocol);
 int sameSocketAddress(struct sockaddr_storage *a, struct sockaddr_storage *b);
+int getAddrInfoWithProto(char *address, char *port, int protocol, struct addrinfo **ai);
 uint16_t getPort(struct addrinfo* ai);

src/parse.peg

@@ -31,6 +31,10 @@
 	result = (EOF == yyc) ? 0 : (*(buf) = yyc, 1); \
 }
 #define PARSE_ERROR exit(1);
+#define MEMORY_ERROR { \
+		logError("could not allocate memory when parsing configuration.\n"); \
+		exit(1); \
+	}
 
 #if defined __clang__
 #pragma clang diagnostic ignored "-Wunused-parameter"
@@ -53,7 +57,13 @@ server-rule  =  bind-address - bind-port - connect-address - connect-port (-? se
 		yy->connectAddress, yy->connectPort, yy->connectProto,
 		yy->serverTimeout > 0 ? yy->serverTimeout : RINETD_DEFAULT_UDP_TIMEOUT,
 		yy->sourceAddress);
+	free(yy->bindAddress);
+	free(yy->connectAddress);
+	free(yy->sourceAddress);
 	yy->bindAddress = yy->connectAddress = yy->sourceAddress = NULL;
+	free(yy->bindPort);
+	free(yy->connectPort);
+	yy->bindPort = yy->connectPort = NULL;
 	yy->serverTimeout = 0;
 }
 
@@ -66,13 +76,11 @@ server-options   =  "[" -? option-list -? "]"
 option-list     =  option (-? ',' -? option-list)?
 option          =  (option-timeout | option-source)
 option-timeout  =  "timeout" -? "=" -? < number >    { yy->serverTimeout = atoi(yytext); }
-option-source   =  "src"     -? "=" -? < address >   { free(yy->sourceAddress);
-                                                       yy->sourceAddress = strdup(yytext); }
+option-source   =  "src"     -? "=" -? < address >   { yy->sourceAddress = strdup(yytext); }
 
 full-port  =  port proto
 
-port   = < (number | service) >   { free(yy->tmpPort);
-                                    yy->tmpPort = strdup(yytext); }
+port   = < (number | service) >   { yy->tmpPort = strdup(yytext); }
 proto  = '/tcp'                   { yy->tmpProto = IPPROTO_TCP; }
        | '/udp'                   { yy->tmpProto = IPPROTO_UDP; }
        | ''                       { yy->tmpProto = IPPROTO_TCP; }
@@ -82,15 +90,15 @@ auth-rule  =  auth-key - < pattern >
 	allRules = (Rule *)
 		realloc(allRules, sizeof(Rule) * (allRulesCount + 1));
 	if (!allRules) {
-		PARSE_ERROR;
+		MEMORY_ERROR;
 	}
 	allRules[allRulesCount].pattern = strdup(yytext);
 	if (!allRules[allRulesCount].pattern) {
-		PARSE_ERROR;
+		MEMORY_ERROR;
 	}
 	allRules[allRulesCount].type = yy->isAuthAllow ? allowRule : denyRule;
 	if (seTotal > 0) {
-		if (seInfo[seTotal - 1].rulesStart == 0) {
+		if (seInfo[seTotal - 1].rulesStart == 0 && seInfo[seTotal - 1].rulesCount == 0) {
 			seInfo[seTotal - 1].rulesStart = allRulesCount;
 		}
 		++seInfo[seTotal - 1].rulesCount;
@@ -106,7 +114,7 @@ logfile  =  "logfile" - < filename >
 {
 	logFileName = strdup(yytext);
 	if (!logFileName) {
-		PARSE_ERROR;
+		MEMORY_ERROR;
 	}
 }
 
@@ -114,7 +122,7 @@ pidlogfile  =  "pidlogfile" - < filename >
 {
 	pidLogFileName = strdup(yytext);
 	if (!pidLogFileName) {
-		PARSE_ERROR;
+		MEMORY_ERROR;
 	}
 }
 
@@ -125,7 +133,7 @@ logcommon  =  "logcommon"
 
 invalid_syntax  =  < (!eol .)+ > eol
 {
-	fprintf(stderr, "rinetd: invalid syntax at line %d: %s\n",
+	logError("invalid syntax at line %d: %s\n",
 	        yy->currentLine, yytext);
 	PARSE_ERROR; /* FIXME */
 }
@@ -135,9 +143,10 @@ address  =  ipv4 | ipv6 | hostname
 pattern  =  (hexdigit | '[' | ']' | ':' | '.' | [*?] )+
 number   =  digit+
 
-ipv4     =  number '.' number '.' number '.' number | '0'
-ipv6     =  (hexdigit | ':')+ | '[' (hexdigit | ':')+ ']'
-hostname =  (label '.')* name '.'?
+ipv4      =  number '.' number '.' number '.' number | '0'
+ipv6      = '[' bare_ipv6 ']' | bare_ipv6
+bare_ipv6 =  hexdigit* ':' (hexdigit | ':')* # Must have at least one ':'
+hostname  =  (label '.')* name '.'?
 
 
 name     =  id ('-' | id | digit)*
@@ -159,19 +168,17 @@ void parseConfiguration(char const *file)
 {
 	FILE *in = fopen(file, "r");
 	if (!in) {
-		PARSE_ERROR;
+		logError("could not open configuration file %s.\n", file);
+		exit(1);
 	}
 
 	yycontext ctx;
 	memset(&ctx, 0, sizeof(yycontext));
 	ctx.fp = in;
 	if (!yyparse(&ctx)) {
-		syslog(LOG_ERR, "invalid syntax "
-			"on file %s, line %d.\n", file, -1);
+		logError("invalid syntax in file %s, line %d.\n", file, -1);
 		exit(1);
 	}
-	free(ctx.sourceAddress);
-	free(ctx.tmpPort);
 	yyrelease(&ctx);
 
 	fclose(in);

src/rinetd.c

@@ -28,9 +28,11 @@
 #	elif HAVE_SYS_TIME_H
 #		include <sys/time.h>
 #	endif
+#	include <syslog.h>
 #endif /* _WIN32 */
 
 #include <stdio.h>
+#include <stdarg.h>
 #include <string.h>
 #include <signal.h>
 #include <stdlib.h>
@@ -106,11 +108,13 @@ enum {
 	logDenied,
 };
 
-RinetdOptions options = {
+static RinetdOptions options = {
 	RINETD_CONFIG_FILE,
 	0,
 };
 
+static int forked = 0;
+
 static void selectPass(void);
 static void handleWrite(ConnectionInfo *cnx, Socket *socket, Socket *other_socket);
 static void handleRead(ConnectionInfo *cnx, Socket *socket, Socket *other_socket);
@@ -158,15 +162,19 @@ int main(int argc, char *argv[])
 
 	readArgs(argc, argv, &options);
 
+	if (!options.foreground) {
 #if HAVE_DAEMON && !DEBUG
-	if (!options.foreground && daemon(0, 0) != 0) {
-		exit(0);
-	}
+		if (daemon(0, 0) != 0) {
+			exit(0);
+		}
+		forked = 1;
 #elif HAVE_FORK && !DEBUG
-	if (!options.foreground && fork() != 0) {
-		exit(0);
-	}
+		if (fork() != 0) {
+			exit(0);
+		}
+		forked = 1;
 #endif
+	}
 
 #if HAVE_SIGACTION
 	struct sigaction act;
@@ -188,7 +196,7 @@ int main(int argc, char *argv[])
 		registerPID(pidLogFileName ? pidLogFileName : RINETD_PID_FILE);
 	}
 
-	syslog(LOG_INFO, "Starting redirections...\n");
+	logInfo("starting redirections...\n");
 	while (1) {
 		selectPass();
 	}
@@ -196,6 +204,38 @@ int main(int argc, char *argv[])
 	return 0;
 }
 
+void logError(char const *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+#if !_WIN32
+	if (forked)
+		vsyslog(LOG_ERR, fmt, ap);
+	else
+#endif
+	{
+		fprintf(stderr, "rinetd error: ");
+		vfprintf(stderr, fmt, ap);
+	}
+	va_end(ap);
+}
+
+void logInfo(char const *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+#if !_WIN32
+	if (forked)
+		vsyslog(LOG_INFO, fmt, ap);
+	else
+#endif
+	{
+		fprintf(stderr, "rinetd: ");
+		vfprintf(stderr, fmt, ap);
+	}
+	va_end(ap);
+}
+
 static void clearConfiguration(void) {
 	/* Remove references to server information */
 	for (int i = 0; i < coTotal; ++i) {
@@ -250,7 +290,7 @@ static void readConfiguration(char const *file) {
 		if (logFile) {
 			setvbuf(logFile, NULL, _IONBF, 0);
 		} else {
-			syslog(LOG_ERR, "could not open %s to append (%m).\n",
+			logError("could not open %s to append (%m).\n",
 				logFileName);
 		}
 	}
@@ -261,22 +301,21 @@ void addServer(char *bindAddress, char *bindPort, int bindProtocol,
                int serverTimeout, char *sourceAddress)
 {
 	ServerInfo si = {
-		.fromHost = bindAddress,
-		.toHost = connectAddress,
+		.fromHost = strdup(bindAddress),
+		.toHost = strdup(connectAddress),
 		.serverTimeout = serverTimeout,
 	};
 
 	/* Make a server socket */
-	struct addrinfo hints = getAddrInfoHint(bindProtocol), *ai;
-	int ret = getaddrinfo(bindAddress, bindPort, &hints, &ai);
+	struct addrinfo *ai;
+	int ret = getAddrInfoWithProto(bindAddress, bindPort, bindProtocol, &ai);
 	if (ret != 0) {
-		fprintf(stderr, "rinetd: getaddrinfo error: %s\n", gai_strerror(ret));
 		exit(1);
 	}
 
 	si.fd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 	if (si.fd == INVALID_SOCKET) {
-		syslog(LOG_ERR, "couldn't create server socket! (%m)\n");
+		logError("couldn't create server socket! (%m)\n");
 		freeaddrinfo(ai);
 		exit(1);
 	}
@@ -285,7 +324,7 @@ void addServer(char *bindAddress, char *bindPort, int bindProtocol,
 	setsockopt(si.fd, SOL_SOCKET, SO_REUSEADDR, (const char *)&tmp, sizeof(tmp));
 
 	if (bind(si.fd, ai->ai_addr, ai->ai_addrlen) == SOCKET_ERROR) {
-		syslog(LOG_ERR, "couldn't bind to address %s port %s (%m)\n",
+		logError("couldn't bind to address %s port %s (%m)\n",
 			bindAddress, bindPort);
 		closesocket(si.fd);
 		freeaddrinfo(ai);
@@ -295,7 +334,7 @@ void addServer(char *bindAddress, char *bindPort, int bindProtocol,
 	if (bindProtocol == IPPROTO_TCP) {
 		if (listen(si.fd, RINETD_LISTEN_BACKLOG) == SOCKET_ERROR) {
 			/* Warn -- don't exit. */
-			syslog(LOG_ERR, "couldn't listen to address %s port %s (%m)\n",
+			logError("couldn't listen to address %s port %s (%m)\n",
 				bindAddress, bindPort);
 			/* XXX: check whether this is correct */
 			closesocket(si.fd);
@@ -308,10 +347,8 @@ void addServer(char *bindAddress, char *bindPort, int bindProtocol,
 	si.fromAddrInfo = ai;
 
 	/* Resolve destination address. */
-	hints = getAddrInfoHint(connectProtocol);
-	ret = getaddrinfo(connectAddress, connectPort, &hints, &ai);
+	ret = getAddrInfoWithProto(connectAddress, connectPort, connectProtocol, &ai);
 	if (ret != 0) {
-		fprintf(stderr, "rinetd: getaddrinfo error: %s\n", gai_strerror(ret));
 		freeaddrinfo(si.fromAddrInfo);
 		closesocket(si.fd);
 		exit(1);
@@ -320,10 +357,8 @@ void addServer(char *bindAddress, char *bindPort, int bindProtocol,
 
 	/* Resolve source address if applicable. */
 	if (sourceAddress) {
-		hints = getAddrInfoHint(connectProtocol);
-		ret = getaddrinfo(sourceAddress, NULL, &hints, &ai);
+		ret = getAddrInfoWithProto(sourceAddress, NULL, connectProtocol, &ai);
 		if (ret != 0) {
-			fprintf(stderr, "rinetd: getaddrinfo error: %s\n", gai_strerror(ret));
 			freeaddrinfo(si.fromAddrInfo);
 			freeaddrinfo(si.toAddrInfo);
 			exit(1);
@@ -413,7 +448,7 @@ static ConnectionInfo *findAvailableConnection(void)
 	int oldTotal = coTotal;
 	setConnectionCount(coTotal * 4 / 3 + 8);
 	if (coTotal == oldTotal) {
-		syslog(LOG_ERR, "not enough memory to add slots. "
+		logError("not enough memory to add slots. "
 			"Currently %d slots.\n", coTotal);
 		/* Go back to the previous total number of slots */
 		return NULL;
@@ -650,7 +685,7 @@ static void handleAccept(ServerInfo const *srv)
 		/* In TCP mode, get remote address using accept(). */
 		nfd = accept(srv->fd, (struct sockaddr *)&addr, &addrlen);
 		if (nfd == INVALID_SOCKET) {
-			syslog(LOG_ERR, "accept(%llu): %m\n", (long long unsigned int)srv->fd);
+			logError("accept(%llu): %m\n", (long long unsigned int)srv->fd);
 			logEvent(NULL, srv, logAcceptFailed);
 			return;
 		}
@@ -671,7 +706,7 @@ static void handleAccept(ServerInfo const *srv)
 			if (GetLastError() == WSAEINPROGRESS) {
 				return;
 			}
-			syslog(LOG_ERR, "recvfrom(%llu): %m\n", (long long unsigned int)srv->fd);
+			logError("recvfrom(%llu): %m\n", (long long unsigned int)srv->fd);
 			logEvent(NULL, srv, logAcceptFailed);
 			return;
 		}
@@ -730,7 +765,7 @@ static void handleAccept(ServerInfo const *srv)
 	struct addrinfo* to = srv->toAddrInfo;
 	cnx->local.fd = socket(to->ai_family, to->ai_socktype, to->ai_protocol);
 	if (cnx->local.fd == INVALID_SOCKET) {
-		syslog(LOG_ERR, "socket(): %m\n");
+		logError("socket(): %m\n");
 		if (cnx->remote.protocol == IPPROTO_TCP)
 			closesocket(cnx->remote.fd);
 		cnx->remote.fd = INVALID_SOCKET;
@@ -746,7 +781,7 @@ static void handleAccept(ServerInfo const *srv)
 	if (srv->sourceAddrInfo) {
 		if (bind(cnx->local.fd, srv->sourceAddrInfo->ai_addr,
 				srv->sourceAddrInfo->ai_addrlen) == SOCKET_ERROR) {
-			syslog(LOG_ERR, "bind(): %m\n");
+			logError("bind(): %m\n");
 		}
 	}
 
@@ -866,7 +901,7 @@ RETSIGTYPE plumber(int s)
 RETSIGTYPE hup(int s)
 {
 	(void)s;
-	syslog(LOG_INFO, "Received SIGHUP, reloading configuration...\n");
+	logInfo("received SIGHUP, reloading configuration...\n");
 	/* Learn the new rules */
 	clearConfiguration();
 	readConfiguration(options.conf_file);
@@ -896,8 +931,6 @@ void registerPID(char const *pid_file_name)
 	FILE *pid_file = fopen(pid_file_name, "w");
 	if (pid_file == NULL) {
 		/* non-fatal, non-Linux may lack /var/run... */
-		fprintf(stderr, "rinetd: Couldn't write to "
-			"%s. PID was not logged.\n", pid_file_name);
 		goto error;
 	} else {
 		fprintf(pid_file, "%d\n", getpid());
@@ -907,8 +940,8 @@ void registerPID(char const *pid_file_name)
 	}
 	return;
 error:
-	syslog(LOG_ERR, "Couldn't write to "
-		"%s. PID was not logged (%m).\n", pid_file_name);
+	logError("couldn't write to %s. PID was not logged (%m).\n",
+		pid_file_name);
 #else
 	/* add other systems with wherever they register processes */
 	(void)pid_file_name;
@@ -947,7 +980,7 @@ static void logEvent(ConnectionInfo const *cnx, ServerInfo const *srv, int resul
 	}
 
 	if (result==logNotAllowed || result==logDenied)
-		syslog(LOG_INFO, "%s %s\n"
+		logInfo("%s %s\n"
 			, addressText
 			, logMessages[result]);
 	if (logFile) {
@@ -1014,7 +1047,7 @@ static int readArgs (int argc, char **argv, RinetdOptions *options)
 			case 'c':
 				options->conf_file = optarg;
 				if (!options->conf_file) {
-					syslog(LOG_ERR, "Not enough memory to "
+					fprintf(stderr, "Not enough memory to "
 						"launch rinetd.\n");
 					exit(1);
 				}

src/rinetd.h

@@ -8,17 +8,6 @@
 
 #pragma once
 
-/* Syslog feature */
-
-#if _WIN32
-#	include <stdio.h>
-#	define syslog fprintf
-#	define LOG_ERR stderr
-#	define LOG_INFO stdout
-#else
-#	include <syslog.h>
-#endif /* _WIN32 */
-
 #include <stdint.h>
 
 /* Constants */
@@ -46,6 +35,8 @@ extern FILE *logFile;
 
 /* Functions */
 
+void logError(char const *fmt, ...);
+void logInfo(char const *fmt, ...);
 void addServer(char *bindAddress, char *bindPort, int bindProtocol,
                char *connectAddress, char *connectPort, int connectProtocol,
                int serverTimeout, char *sourceAddress);