README: add some useful links for leak checks

without -Werror=implicit-function-declaration our test for GNU-style
getservbyname_r silently succeeds on NetBSD 10
(because the function exists, so the testcase links successfully).

however NetBSD's version has a completely different signature which
leads to crashes at runtime:

    Program terminated with signal SIGSEGV, Segmentation fault.
    #0  0x0000f1707faa2b78 in free () from /usr/lib/libc.so.12
    [Current thread is 1 (process 25072)]
    (gdb) backtrace
    #0  0x0000f1707faa2b78 in free () from /usr/lib/libc.so.12
    #1  0x0000f1707fac58b0 in _servent_open () from /usr/lib/libc.so.12
    #2  0x0000f1707fac5a60 in setservent_r () from /usr/lib/libc.so.12
    #3  0x0000f1707fac4490 in getservbyname_r () from /usr/lib/libc.so.12
    #4  0x0000f17080235788 in mygetservbyname_r (name=0xf1707f847ab0 "80", proto=0x0, result_buf=0xffffffe29738, buf=0xffffffe29338 "", buflen=1024, result=0xffffffe29758) at src/core.c:917
    #5  0x0000f17080235aa8 in proxy_getaddrinfo (node=0xf1707f847ba0 "4get.nadeko.net", service=0xf1707f847ab0 "80", hints=0xffffffe29978, res=0xffffffe29968) at src/core.c:1004
    #6  0x0000f17080238a94 in getaddrinfo (node=0xf1707f847ba0 "4get.nadeko.net", service=0xf1707f847ab0 "80", hints=0xffffffe29978, res=0xffffffe29968) at src/libproxychains.c:795

netbsd's signature is:
struct servent *
getservbyname_r(const char *name, const char *proto, struct servent *sp,
    struct servent_data *sd)

and basically the first thing it does is to free existing members of the
sd struct, which obviously crashes when the thing passed as 4th argument
isn't actually that kind of struct.

.gitignore

@@ -1,4 +1,5 @@
 proxychains4
+proxychains4-daemon
 *.bz2
 *.xz
 *.o

Makefile

@@ -11,7 +11,8 @@ bindir = $(exec_prefix)/bin
 prefix = /usr/local/
 includedir = $(prefix)/include
 libdir = $(prefix)/lib
-sysconfdir=$(prefix)/etc
+sysconfdir = $(prefix)/etc
+zshcompletiondir = $(prefix)/share/zsh/site-functions
 
 OBJS = src/common.o src/main.o
 
@@ -48,6 +49,7 @@ PXCHAINS = proxychains4
 PXCHAINS_D = proxychains4-daemon
 ALL_TOOLS = $(PXCHAINS) $(PXCHAINS_D)
 ALL_CONFIGS = src/proxychains.conf
+ZSH_COMPLETION = completions/zsh/_proxychains4
 
 -include config.mak
 
@@ -68,9 +70,13 @@ $(DESTDIR)$(libdir)/%: %
 $(DESTDIR)$(sysconfdir)/%: src/%
 	$(INSTALL) -D -m 644 $< $@
 
+$(DESTDIR)$(zshcompletiondir)/%: completions/zsh/%
+	$(INSTALL) -D -m 644 $< $@
+
 install-libs: $(ALL_LIBS:%=$(DESTDIR)$(libdir)/%)
 install-tools: $(ALL_TOOLS:%=$(DESTDIR)$(bindir)/%)
 install-config: $(ALL_CONFIGS:src/%=$(DESTDIR)$(sysconfdir)/%)
+install-zsh-completion: $(ZSH_COMPLETION:completions/zsh/%=$(DESTDIR)$(zshcompletiondir)/%)
 
 clean:
 	rm -f $(ALL_LIBS)
@@ -87,14 +93,14 @@ src/version.o: src/version.h
 	$(CC) $(CPPFLAGS) $(CFLAGS) $(CFLAGS_MAIN) $(INC) $(PIC) -c -o $@ $<
 
 $(LDSO_PATHNAME): $(LOBJS)
-	$(CC) $(LDFLAGS) $(LD_SET_SONAME)$(LDSO_PATHNAME) $(USER_LDFLAGS) \
+	$(CC) $(LDFLAGS) $(FAT_LDFLAGS) $(LD_SET_SONAME)$(LDSO_PATHNAME) \
-		-shared -o $@ $^ $(SOCKET_LIBS)
+		$(USER_LDFLAGS) -shared -o $@ $^ $(SOCKET_LIBS)
 
 $(PXCHAINS): $(OBJS)
-	$(CC) $^ $(USER_LDFLAGS) $(LIBDL) -o $@
+	$(CC) $^ $(FAT_BIN_LDFLAGS) $(USER_LDFLAGS) $(LIBDL) -o $@
 
 $(PXCHAINS_D): $(DOBJS)
-	$(CC) $^ $(USER_LDFLAGS) -o $@
+	$(CC) $^ $(FAT_BIN_LDFLAGS) $(USER_LDFLAGS) -o $@
 
 
-.PHONY: all clean install install-config install-libs install-tools
+.PHONY: all clean install install-config install-libs install-tools install-zsh-completion

README

@@ -1,4 +1,4 @@
-ProxyChains-NG ver 4.16 README
+ProxyChains-NG ver 4.17 README
 =============================
 
   ProxyChains is a UNIX program, that hooks network-related libc functions
@@ -52,6 +52,15 @@ ProxyChains-NG ver 4.16 README
 
 Changelog:
 ----------
+Version 4.17
+- add hook for close_range function, fixing newer versions of openssh
+- fat-binary-m1 option for mac
+- fix DNS error handling in proxy_dns_old
+- simplify init code
+- fix openbsd preloading
+- fix double-close in multithreaded apps
+- various improvements to configure script
+
 Version 4.16
 - fix regression in configure script linker flag detection
 - remove 10 year old workaround for wrong glibc getnameinfo signature
@@ -254,6 +263,15 @@ Known Problems:
   there are unconfirmed reports that it works as root though.
   musl libc is unaffected from the bug.
 
+Useful links
+------------
+the following sites may prove useful to check for leaks:
+https://ipfighter.com/
+https://browserleaks.com/webrtc
+https://dnsleaktest.com
+http://check.torproject.org - tor specific
+http://ifconfig.me - can be used via curl
+http://ifconfig.io/
 
 Community:
 ----------

VERSION

@@ -1 +1 @@
-4.16
+4.17

completions/zsh/_proxychains4

@@ -0,0 +1,8 @@
+#compdef proxychains4
+
+_arguments \
+  '(- : *)--help[More help in README file]' \
+  '-q[makes proxychains quiet - this overrides the config setting]' \
+  '-f[allows one to manually specify a configfile to use]: :_files' \
+  '(-)1: :{_command_names -e}' \
+  '*:: :_normal'

configure

@@ -86,6 +86,8 @@ usage() {
 	echo "	if set to yes ignores CVE-2015-3887 and makes it possible"
 	echo "	to preload from current dir (possibly insecure, but handy)"
 	echo "--fat-binary : build for both i386 and x86_64 architectures on 64-bit Macs"
+	echo "--fat-binary-m1 : build for both arm64e and x86_64 architectures on M1 Macs"
+	echo "--fat-binary-m2 : build for arm64, arm64e and x86_64 architectures on M2+ Macs"
 	echo "--hookmethod=dlsym|dyld   hook method for osx. default: auto"
 	echo "  if OSX >= 12 is detected, dyld method will be used if auto."
 	echo "--help : show this text"
@@ -100,6 +102,8 @@ spliteq() {
 }
 
 fat_binary=
+fat_binary_m1=
+fat_binary_m2=
 ignore_cve=no
 hookmethod=auto
 
@@ -115,6 +119,8 @@ parsearg() {
 	--ignore-cve=*) ignore_cve=`spliteq $1`;;
 	--hookmethod=*) hookmethod=`spliteq $1`;;
 	--fat-binary) fat_binary=1;;
+	--fat-binary-m1) fat_binary_m1=1;;
+	--fat-binary-m2) fat_binary_m2=1;;
 	--help) usage;;
 	esac
 }
@@ -174,6 +180,25 @@ ishaiku() {
 }
 
 check_compile 'whether C compiler works' '' 'int main() {return 0;}' || fail 'error: install a C compiler and library'
+check_compile 'whether libc headers are complete' '' '#include <netdb.h>\nint main() {return 0;}' || fail 'error: necessary libc headers are not installed'
+check_compile 'whether C compiler understands -Wno-unknown-pragmas' '-Wno-unknown-pragmas' 'int main() {return 0;}'
+check_compile 'whether C compiler understands -Werror=implicit-function-declaration' '-Werror=implicit-function-declaration' 'int main() {return 0;}'
+
+if ! check_compile 'whether getnameinfo() servlen argument is POSIX compliant (socklen_t)' "-DGN_NODELEN_T=socklen_t -DGN_SERVLEN_T=socklen_t -DGN_FLAGS_T=int" \
+'#define _GNU_SOURCE\n#include <netdb.h>\nint getnameinfo(const struct sockaddr *, socklen_t, char *, socklen_t, char *, socklen_t, int);int main() {\nreturn 0;}' ; then
+ # GLIBC < 2.14
+ if ! check_compile 'whether getnameinfo() flags argument is unsigned' "-DGN_NODELEN_T=socklen_t -DGN_SERVLEN_T=socklen_t -DGN_FLAGS_T=unsigned" \
+  '#define _GNU_SOURCE\n#include <netdb.h>\nint getnameinfo(const struct sockaddr *, socklen_t, char *, socklen_t, char *, socklen_t, unsigned);int main() {\nreturn 0;}' ; then
+  if ! check_compile 'whether getnameinfo() servlen argument is size_t' "-DGN_NODELEN_T=socklen_t -DGN_SERVLEN_T=size_t -DGN_FLAGS_T=int" \
+   '#define _GNU_SOURCE\n#include <netdb.h>\nint getnameinfo(const struct sockaddr *, socklen_t, char *, socklen_t, char *, size_t, int);int main() {\nreturn 0;}' ; then
+   # OpenBSD & FreeBSD
+   if ! check_compile 'whether getnameinfo() servlen and nodelen argument is size_t' "-DGN_NODELEN_T=size_t -DGN_SERVLEN_T=size_t -DGN_FLAGS_T=int" \
+    '#define _GNU_SOURCE\n#include <netdb.h>\nint getnameinfo(const struct sockaddr *, socklen_t, char *, size_t, char *, size_t, int);int main() {\nreturn 0;}' ; then
+     fail "failed to detect getnameinfo signature"
+   fi
+  fi
+ fi
+fi
 
 check_compile 'whether we have GNU-style getservbyname_r()' "-DHAVE_GNU_GETSERVBYNAME_R" \
 '#define _GNU_SOURCE\n#include <netdb.h>\nint main() {\nstruct servent *se = 0;struct servent se_buf;char buf[1024];\ngetservbyname_r("foo", (void*) 0, &se_buf, buf, sizeof(buf), &se);\nreturn 0;}'
@@ -196,6 +221,7 @@ check_define __APPLE__ && {
 	fi
 }
 check_define __FreeBSD__ && bsd_detected=true
+check_define __NetBSD__ && bsd_detected=true
 check_define __OpenBSD__ && {
 bsd_detected=true
 echo "CFLAGS+=-DIS_OPENBSD">>config.mak
@@ -225,7 +251,7 @@ check_link "whether we can use -Wl,--no-as-needed" "-Wl,--no-as-needed" \
 LD_SONAME_FLAG=
 printf "checking what's the option to use in linker to set library name ... "
 for o in --soname -h -soname -install_name; do
-	check_link_silent "-shared -Wl,$o,libconftest.so" "void test_func(int a) {}" && LD_SONAME_FLAG=$o && break
+	check_link_silent "-shared -Wl,$o,libconftest.so" "void test_func(void) {}" && LD_SONAME_FLAG=$o && break
 done
 if [ -z "$LD_SONAME_FLAG" ]; then
 	printf '\ncannot find an option to set library name\n'
@@ -259,7 +285,20 @@ if ismac ; then
 	if ismac64 && [ "$fat_binary" = 1 ] ; then
 		echo "Configuring a fat binary for i386 and x86_64"
 		echo "MAC_CFLAGS+=-arch i386 -arch x86_64">>config.mak
-		echo "LDFLAGS+=-arch i386 -arch x86_64">>config.mak
+		echo "FAT_LDFLAGS=-arch i386 -arch x86_64">>config.mak
+		echo "FAT_BIN_LDFLAGS=-arch i386 -arch x86_64">>config.mak
+	fi
+	if [ "$fat_binary_m1" = 1 ] ; then
+		echo "Configuring a fat binary for arm64[e] and x86_64"
+		echo "MAC_CFLAGS+=-arch arm64 -arch arm64e -arch x86_64">>config.mak
+		echo "FAT_LDFLAGS=-arch arm64 -arch arm64e -arch x86_64">>config.mak
+		echo "FAT_BIN_LDFLAGS=-arch arm64 -arch x86_64">>config.mak
+	fi
+	if [ "$fat_binary_m2" = 1 ] ; then
+		echo "Configuring a fat binary for arm64[e] and x86_64"
+		echo "MAC_CFLAGS+=-arch arm64 -arch arm64e -arch x86_64">>config.mak
+		echo "FAT_LDFLAGS=-arch arm64 -arch arm64e -arch x86_64">>config.mak
+		echo "FAT_BIN_LDFLAGS=-arch arm64 -arch arm64e -arch x86_64">>config.mak
 	fi
 elif isbsd ; then
 	echo LIBDL=>>config.mak
@@ -274,3 +313,6 @@ elif ishaiku ; then
 fi
 
 echo "Done, now run $make_cmd && $make_cmd install"
+if [ "$fat_binary_m2" = 1 ] ; then
+echo "Don't forget to run csrutil disable and sudo nvram boot-args=-arm64e_preview_abi"
+fi

src/core.c

@@ -462,8 +462,10 @@ static int start_chain(int *fd, proxy_data * pd, char *begin_mark) {
 	error1:
 	proxychains_write_log(TP " timeout\n");
 	error:
-	if(*fd != -1)
+	if(*fd != -1) {
 		close(*fd);
+		*fd = -1;
+	}
 	return SOCKET_ERROR;
 }
 
@@ -520,9 +522,9 @@ static unsigned int calc_alive(proxy_data * pd, unsigned int proxy_count) {
 }
 
 
-static int chain_step(int ns, proxy_data * pfrom, proxy_data * pto) {
+static int chain_step(int *ns, proxy_data * pfrom, proxy_data * pto) {
 	int retcode = -1;
-	char *hostname;
+	char *hostname, *errmsg = 0;
 	char hostname_buf[MSG_LEN_MAX];
 	char ip_buf[INET6_ADDRSTRLEN];
 	int v6 = pto->ip.is_v6;
@@ -536,31 +538,34 @@ static int chain_step(int ns, proxy_data * pfrom, proxy_data * pto) {
 	usenumericip:
 		if(!inet_ntop(v6?AF_INET6:AF_INET,pto->ip.addr.v6,ip_buf,sizeof ip_buf)) {
 			pto->ps = DOWN_STATE;
-			proxychains_write_log("<--ip conversion error!\n");
+			errmsg = "<--ip conversion error!\n";
-			close(ns);
+			retcode = SOCKET_ERROR;
-			return SOCKET_ERROR;
+			goto err;
 		}
 		hostname = ip_buf;
 	}
 
 	proxychains_write_log(TP " %s:%d ", hostname, htons(pto->port));
-	retcode = tunnel_to(ns, pto->ip, pto->port, pfrom->pt, pfrom->user, pfrom->pass);
+	retcode = tunnel_to(*ns, pto->ip, pto->port, pfrom->pt, pfrom->user, pfrom->pass);
 	switch (retcode) {
 		case SUCCESS:
 			pto->ps = BUSY_STATE;
 			break;
 		case BLOCKED:
 			pto->ps = BLOCKED_STATE;
-			proxychains_write_log("<--denied\n");
+			errmsg = "<--denied\n";
-			close(ns);
+			goto err;
-			break;
 		case SOCKET_ERROR:
 			pto->ps = DOWN_STATE;
-			proxychains_write_log("<--socket error or timeout!\n");
+			errmsg = "<--socket error or timeout!\n";
-			close(ns);
+			goto err;
-			break;
 	}
 	return retcode;
+err:
+	if(errmsg) proxychains_write_log(errmsg);
+	if(*ns != -1) close(*ns);
+	*ns = -1;
+	return retcode;
 }
 
 int connect_proxy_chain(int sock, ip_type target_ip,
@@ -596,7 +601,7 @@ int connect_proxy_chain(int sock, ip_type target_ip,
 				p2 = select_proxy(FIFOLY, pd, proxy_count, &offset);
 				if(!p2)
 					break;
-				if(SUCCESS != chain_step(ns, p1, p2)) {
+				if(SUCCESS != chain_step(&ns, p1, p2)) {
 					PDEBUG("GOTO AGAIN 1\n");
 					goto again;
 				}
@@ -605,7 +610,7 @@ int connect_proxy_chain(int sock, ip_type target_ip,
 			//proxychains_write_log(TP);
 			p3->ip = target_ip;
 			p3->port = target_port;
-			if(SUCCESS != chain_step(ns, p1, p3))
+			if(SUCCESS != chain_step(&ns, p1, p3))
 				goto error;
 			break;
 
@@ -643,7 +648,7 @@ int connect_proxy_chain(int sock, ip_type target_ip,
 					/* Try from the beginning to where we started */
 					offset = 0;
 					continue;
-				} else if(SUCCESS != chain_step(ns, p1, p2)) {
+				} else if(SUCCESS != chain_step(&ns, p1, p2)) {
 					PDEBUG("GOTO AGAIN 1\n");
 					goto again;
 				} else
@@ -655,7 +660,7 @@ int connect_proxy_chain(int sock, ip_type target_ip,
 			p3->port = target_port;
 			proxychains_proxy_offset = offset+1;
 			PDEBUG("pd_offset = %d, curr_len = %d\n", proxychains_proxy_offset, curr_len);
-			if(SUCCESS != chain_step(ns, p1, p3))
+			if(SUCCESS != chain_step(&ns, p1, p3))
 				goto error;
 			break;
 
@@ -673,7 +678,7 @@ int connect_proxy_chain(int sock, ip_type target_ip,
 			while(offset < proxy_count) {
 				if(!(p2 = select_proxy(FIFOLY, pd, proxy_count, &offset)))
 					break;
-				if(SUCCESS != chain_step(ns, p1, p2)) {
+				if(SUCCESS != chain_step(&ns, p1, p2)) {
 					PDEBUG("chain_step failed\n");
 					goto error_strict;
 				}
@@ -682,7 +687,7 @@ int connect_proxy_chain(int sock, ip_type target_ip,
 			//proxychains_write_log(TP);
 			p3->ip = target_ip;
 			p3->port = target_port;
-			if(SUCCESS != chain_step(ns, p1, p3))
+			if(SUCCESS != chain_step(&ns, p1, p3))
 				goto error;
 			break;
 
@@ -698,7 +703,7 @@ int connect_proxy_chain(int sock, ip_type target_ip,
 			while(++curr_len < max_chain) {
 				if(!(p2 = select_proxy(RANDOMLY, pd, proxy_count, &offset)))
 					goto error_more;
-				if(SUCCESS != chain_step(ns, p1, p2)) {
+				if(SUCCESS != chain_step(&ns, p1, p2)) {
 					PDEBUG("GOTO AGAIN 2\n");
 					goto again;
 				}
@@ -707,7 +712,7 @@ int connect_proxy_chain(int sock, ip_type target_ip,
 			//proxychains_write_log(TP);
 			p3->ip = target_ip;
 			p3->port = target_port;
-			if(SUCCESS != chain_step(ns, p1, p3))
+			if(SUCCESS != chain_step(&ns, p1, p3))
 				goto error;
 
 	}
@@ -824,7 +829,8 @@ struct hostent* proxy_gethostbyname_old(const char *name)
 			close(pipe_fd[0]);
 got_buff:
 			l = strlen(buff);
-			if(l && buff[l-1] == '\n') buff[l-1] = 0;
+			if (!l) goto err_dns;
+			if (buff[l-1] == '\n') buff[l-1] = 0;
 			addr = inet_addr(buff);
 			if (addr == (in_addr_t) (-1))
 				goto err_dns;
@@ -839,8 +845,7 @@ got_buff:
 			name, inet_ntoa(*(struct in_addr*)&addr));
 	return &hostent_space;
 err_dns:
-	proxychains_write_log("|DNS-response|: %s does not exist\n", name);
+	proxychains_write_log("|DNS-response|: %s lookup error\n", name);
-	perror("err_dns");
 err:
 	return NULL;
 }
@@ -969,12 +974,13 @@ int proxy_getaddrinfo(const char *node, const char *service, const struct addrin
 		node?node:"",service?service:"",hints?(int)hints->ai_flags:0);
 
 	space = calloc(1, sizeof(struct addrinfo_data));
-	if(!space) goto err1;
+	if(!space) return EAI_MEMORY;
 
 	if(node && !my_inet_aton(node, space)) {
 		/* some folks (nmap) use getaddrinfo() with AI_NUMERICHOST to check whether a string
 		   containing a numeric ip was passed. we must return failure in that case. */
 		if(hints && (hints->ai_flags & AI_NUMERICHOST)) {
+err_nn:
 			free(space);
 			return EAI_NONAME;
 		}
@@ -987,13 +993,13 @@ int proxy_getaddrinfo(const char *node, const char *service, const struct addrin
 			memcpy(&((struct sockaddr_in *) &space->sockaddr_space)->sin_addr,
 			       *(hp->h_addr_list), sizeof(in_addr_t));
 		else
-			goto err2;
+			goto err_nn;
 	} else if(node) {
 		af = ((struct sockaddr_in *) &space->sockaddr_space)->sin_family;
 	} else if(!node && !(hints->ai_flags & AI_PASSIVE)) {
 		af = ((struct sockaddr_in *) &space->sockaddr_space)->sin_family = AF_INET;
 		memcpy(&((struct sockaddr_in *) &space->sockaddr_space)->sin_addr,
-		       (char[]){127,0,0,1}, 4);
+		       "\177\0\0\1", 4);
 	}
 	if(service) mygetservbyname_r(service, NULL, &se_buf, buf, sizeof(buf), &se);
 
@@ -1026,12 +1032,5 @@ int proxy_getaddrinfo(const char *node, const char *service, const struct addrin
 #endif
 		p->ai_flags = (AI_V4MAPPED | AI_ADDRCONFIG);
 	}
-
-	goto out;
-	err2:
-	free(space);
-	err1:
-	return 1;
-	out:
 	return 0;
 }

src/core.h

@@ -100,16 +100,17 @@ int connect_proxy_chain (int sock, ip_type target_ip, unsigned short target_port
 void proxychains_write_log(char *str, ...);
 
 typedef int (*close_t)(int);
+typedef int (*close_range_t)(unsigned, unsigned, int);
 typedef int (*connect_t)(int, const struct sockaddr *, socklen_t);
 typedef struct hostent* (*gethostbyname_t)(const char *);
-typedef int (*freeaddrinfo_t)(struct addrinfo *);
+typedef void (*freeaddrinfo_t)(struct addrinfo *);
 typedef struct hostent *(*gethostbyaddr_t) (const void *, socklen_t, int);
 
 typedef int (*getaddrinfo_t)(const char *, const char *, const struct addrinfo *, 
 			     struct addrinfo **);
 
 typedef int (*getnameinfo_t) (const struct sockaddr *, socklen_t, char *, 
-			      socklen_t, char *, socklen_t, int);
+			      GN_NODELEN_T, char *, GN_SERVLEN_T, GN_FLAGS_T);
 
 typedef ssize_t (*sendto_t) (int sockfd, const void *buf, size_t len, int flags,
 			     const struct sockaddr *dest_addr, socklen_t addrlen);

src/daemon/daemon.c

@@ -5,6 +5,7 @@
 
 */
 
+#undef _GNU_SOURCE
 #define _GNU_SOURCE
 #include <unistd.h>
 #define _POSIX_C_SOURCE 200809L

src/libproxychains.c

@@ -56,6 +56,7 @@ connect_t true___xnet_connect;
 #endif
 
 close_t true_close;
+close_range_t true_close_range;
 connect_t true_connect;
 gethostbyname_t true_gethostbyname;
 getaddrinfo_t true_getaddrinfo;
@@ -86,13 +87,14 @@ static int init_l = 0;
 
 static void get_chain_data(proxy_data * pd, unsigned int *proxy_count, chain_type * ct);
 
-static void* load_sym(char* symname, void* proxyfunc) {
+static void* load_sym(char* symname, void* proxyfunc, int is_mandatory) {
-
 	void *funcptr = dlsym(RTLD_NEXT, symname);
 
-	if(!funcptr) {
+	if(is_mandatory && !funcptr) {
 		fprintf(stderr, "Cannot load symbol '%s' %s\n", symname, dlerror());
 		exit(1);
+	} else if (!funcptr) {
+		return funcptr;
 	} else {
 		PDEBUG("loaded symbol '%s'" " real addr %p  wrapped addr %p\n", symname, funcptr, proxyfunc);
 	}
@@ -103,17 +105,22 @@ static void* load_sym(char* symname, void* proxyfunc) {
 	return funcptr;
 }
 
-#define INIT() init_lib_wrapper(__FUNCTION__)
-
-
 #include "allocator_thread.h"
 
 const char *proxychains_get_version(void);
 
 static void setup_hooks(void);
 
+typedef struct {
+	unsigned int first, last, flags;
+} close_range_args_t;
+
+/* If there is some `close` or `close_range` system call before do_init, 
+   we buffer it, and actually execute them in do_init. */
 static int close_fds[16];
 static int close_fds_cnt = 0;
+static close_range_args_t close_range_buffer[16];
+static int close_range_buffer_cnt = 0;
 
 static unsigned get_rand_seed(void) {
 #ifdef HAVE_CLOCK_GETTIME
@@ -126,18 +133,28 @@ static unsigned get_rand_seed(void) {
 }
 
 static void do_init(void) {
+	char *env;
+
 	srand(get_rand_seed());
 	core_initialize();
 
-	/* read the config file */
+	env = getenv(PROXYCHAINS_QUIET_MODE_ENV_VAR);
-	get_chain_data(proxychains_pd, &proxychains_proxy_count, &proxychains_ct);
+	if(env && *env == '1')
-	DUMP_PROXY_CHAIN(proxychains_pd, proxychains_proxy_count);
+		proxychains_quiet_mode = 1;
 
 	proxychains_write_log(LOG_PREFIX "DLL init: proxychains-ng %s\n", proxychains_get_version());
 
 	setup_hooks();
 
+	/* read the config file */
+	get_chain_data(proxychains_pd, &proxychains_proxy_count, &proxychains_ct);
+	DUMP_PROXY_CHAIN(proxychains_pd, proxychains_proxy_count);
+
 	while(close_fds_cnt) true_close(close_fds[--close_fds_cnt]);
+	while(close_range_buffer_cnt) {
+		int i = --close_range_buffer_cnt;
+		true_close_range(close_range_buffer[i].first, close_range_buffer[i].last, close_range_buffer[i].flags);
+	}
 	init_l = 1;
 
 	rdns_init(proxychains_resolver);
@@ -156,11 +173,14 @@ static void init_lib_wrapper(const char* caller) {
  * lazily, which has the disadvantage that there's a potential
  * race condition if 2 threads call it before init_l is set
  * and PTHREAD support was disabled */
-#if __GNUC__ > 2
+#if __GNUC__+0 > 2
 __attribute__((constructor))
 static void gcc_init(void) {
-	INIT();
+	init_lib_wrapper(__FUNCTION__);
 }
+#define INIT() do {} while(0)
+#else
+#define INIT() init_lib_wrapper(__FUNCTION__)
 #endif
 
 
@@ -221,7 +241,7 @@ static int proxy_from_string(const char *proxystring,
 		ul = p-u;
 		p++;
 		pl = at-p;
-		if(proxytype == RS_PT_SOCKS5 && (ul > 255 || pl > 255))
+		if(ul > 255 || pl > 255)
 			return 0;
 		memcpy(user_buf, u, ul);
 		user_buf[ul]=0;
@@ -293,10 +313,6 @@ static void get_chain_data(proxy_data * pd, unsigned int *proxy_count, chain_typ
         	exit(1);
 	}
 
-	env = getenv(PROXYCHAINS_QUIET_MODE_ENV_VAR);
-	if(env && *env == '1')
-		proxychains_quiet_mode = 1;
-
 	while(fgets(buf, sizeof(buf), file)) {
 		buff = buf;
 		/* remove leading whitespace */
@@ -335,7 +351,7 @@ static void get_chain_data(proxy_data * pd, unsigned int *proxy_count, chain_typ
 					if(*ct == STRICT_TYPE && proxychains_resolver >= DNSLF_RDNS_START && count > 0) {
 						/* we can allow dns hostnames for all but the first proxy in the list if chaintype is strict, as remote lookup can be done */
 						rdns_init(proxychains_resolver);
-						ip_type4 internal_ip = at_get_ip_for_host(host, strlen(host));
+						ip_type4 internal_ip = rdns_get_ip_for_host(host, strlen(host));
 						pd[count].ip.is_v6 = 0;
 						host_ip->addr.v4 = internal_ip;
 						if(internal_ip.as_int == IPT4_INVALID.as_int)
@@ -587,6 +603,69 @@ static int is_v4inv6(const struct in6_addr *a) {
 	return !memcmp(a->s6_addr, "\0\0\0\0\0\0\0\0\0\0\xff\xff", 12);
 }
 
+static void intsort(int *a, int n) {
+	int i, j, s;
+	for(i=0; i<n; ++i)
+		for(j=i+1; j<n; ++j)
+			if(a[j] < a[i]) {
+				s = a[i];
+				a[i] = a[j];
+				a[j] = s;
+			}
+}
+
+/* Warning: Linux manual says the third arg is `unsigned int`, but unistd.h says `int`. */
+HOOKFUNC(int, close_range, unsigned first, unsigned last, int flags) {
+	if(true_close_range == NULL) {
+		fprintf(stderr, "Calling close_range, but this platform does not provide this system call. ");
+		return -1;
+	}
+	if(!init_l) {
+		/* push back to cache, and delay the execution. */
+		if(close_range_buffer_cnt >= (sizeof close_range_buffer / sizeof close_range_buffer[0])) {
+			errno = ENOMEM;
+			return -1;
+		}
+		int i = close_range_buffer_cnt++;
+		close_range_buffer[i].first = first;
+		close_range_buffer[i].last = last;
+		close_range_buffer[i].flags = flags;
+		return errno = 0;
+	}
+	if(proxychains_resolver != DNSLF_RDNS_THREAD) return true_close_range(first, last, flags);
+
+	/* prevent rude programs (like ssh) from closing our pipes */
+	int res = 0, uerrno = 0, i;
+	int protected_fds[] = {req_pipefd[0], req_pipefd[1], resp_pipefd[0], resp_pipefd[1]};
+	intsort(protected_fds, 4);
+	/* We are skipping protected_fds while calling true_close_range()
+	 * If protected_fds cut the range into some sub-ranges, we close sub-ranges BEFORE cut point in the loop. 
+	 * [first, cut1-1] , [cut1+1, cut2-1] , [cut2+1, cut3-1]
+	 * Finally, we delete the remaining sub-range, outside the loop. [cut3+1, tail]
+	 */
+	int next_fd_to_close = first;
+	for(i = 0; i < 4; ++i) {
+		if(protected_fds[i] < first || protected_fds[i] > last)
+			continue;
+		int prev = (i == 0 || protected_fds[i-1] < first) ? first : protected_fds[i-1]+1;
+		if(prev != protected_fds[i]) {
+			if(-1 == true_close_range(prev, protected_fds[i]-1, flags)) {
+				res = -1;
+				uerrno = errno;
+			}
+		}
+		next_fd_to_close = protected_fds[i]+1;
+	}
+	if(next_fd_to_close <= last) {
+		if(-1 == true_close_range(next_fd_to_close, last, flags)) {
+			res = -1;
+			uerrno = errno;
+		}
+	}
+	errno = uerrno;
+	return res;
+}
+
 HOOKFUNC(int, connect, int sock, const struct sockaddr *addr, unsigned int len) {
 	INIT();
 	PFUNC();
@@ -688,7 +767,7 @@ HOOKFUNC(int, connect, int sock, const struct sockaddr *addr, unsigned int len)
 }
 
 #ifdef IS_SOLARIS
-HOOKFUNC(int, __xnet_connect, int sock, const struct sockaddr *addr, unsigned int len)
+HOOKFUNC(int, __xnet_connect, int sock, const struct sockaddr *addr, unsigned int len) {
 	return connect(sock, addr, len);
 }
 #endif
@@ -729,8 +808,8 @@ HOOKFUNC(void, freeaddrinfo, struct addrinfo *res) {
 }
 
 HOOKFUNC(int, getnameinfo, const struct sockaddr *sa, socklen_t salen,
-	           char *host, socklen_t hostlen, char *serv,
+	           char *host, GN_NODELEN_T hostlen, char *serv,
-	           socklen_t servlen, int flags)
+	           GN_SERVLEN_T servlen, GN_FLAGS_T flags)
 {
 	INIT();
 	PFUNC();
@@ -825,8 +904,11 @@ HOOKFUNC(ssize_t, sendto, int sockfd, const void *buf, size_t len, int flags,
 
 #ifdef MONTEREY_HOOKING
 #define SETUP_SYM(X) do { if (! true_ ## X ) true_ ## X = &X; } while(0)
+#define SETUP_SYM_OPTIONAL(X)
 #else
-#define SETUP_SYM(X) do { if (! true_ ## X ) true_ ## X = load_sym( # X, X ); } while(0)
+#define SETUP_SYM_IMPL(X, IS_MANDATORY) do { if (! true_ ## X ) true_ ## X = load_sym( # X, X, IS_MANDATORY ); } while(0)
+#define SETUP_SYM(X) SETUP_SYM_IMPL(X, 1)
+#define SETUP_SYM_OPTIONAL(X) SETUP_SYM_IMPL(X, 0)
 #endif
 
 static void setup_hooks(void) {
@@ -841,6 +923,7 @@ static void setup_hooks(void) {
 	SETUP_SYM(__xnet_connect);
 #endif
 	SETUP_SYM(close);
+	SETUP_SYM_OPTIONAL(close_range);
 }
 
 #ifdef MONTEREY_HOOKING

src/main.c

@@ -135,16 +135,20 @@ int main(int argc, char *argv[]) {
 	if(!quiet)
 		fprintf(stderr, LOG_PREFIX "preloading %s/%s\n", prefix, dll_name);
 
+#if defined(IS_MAC) || defined(IS_OPENBSD)
+#define LD_PRELOAD_SEP ":"
+#else
+/* Dynlinkers for Linux and most BSDs seem to support space
+   as LD_PRELOAD separator, with colon added only recently.
+   We use the old syntax for maximum compat */
+#define LD_PRELOAD_SEP " "
+#endif
+
 #ifdef IS_MAC
 	putenv("DYLD_FORCE_FLAT_NAMESPACE=1");
 #define LD_PRELOAD_ENV "DYLD_INSERT_LIBRARIES"
-#define LD_PRELOAD_SEP ":"
 #else
 #define LD_PRELOAD_ENV "LD_PRELOAD"
-/* all historic implementations of BSD and linux dynlinkers seem to support
-   space as LD_PRELOAD separator, with colon added only recently.
-   we use the old syntax for maximum compat */
-#define LD_PRELOAD_SEP " "
 #endif
 	char *old_val = getenv(LD_PRELOAD_ENV);
 	snprintf(buf, sizeof(buf), LD_PRELOAD_ENV "=%s/%s%s%s",