Merge branch 'master' into releasev1.32

Signed-off-by: Toni Uhlig <matzeton@googlemail.com>

16 files changed, 125 insertions, 40 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 6d37a49..1d161a2 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -14,6 +14,18 @@ if HAVE_SELINUX
 ptunnel_ng_CFLAGS += -DHAVE_SELINUX=1
 endif
 
+if HAVE_ICMPFILTER
+ptunnel_ng_CFLAGS += -DHAVE_ICMPFILTER=1
+endif
+
+if HAVE_ARC4RANDOM
+ptunnel_ng_CFLAGS += -DHAVE_ARC4RANDOM=1
+else
+if HAVE_RANDOM
+ptunnel_ng_CFLAGS += -DHAVE_RANDOM=1
+endif
+endif
+
 ptunnel_ng_SOURCES = \
 	md5.c \
 	challenge.c \
diff --git a/src/Makefile.in b/src/Makefile.in
index 2c84d72..4d3bc76 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -91,11 +91,14 @@ host_triplet = @host@
 bin_PROGRAMS = ptunnel-ng$(EXEEXT)
 @HAVE_PCAP_TRUE@am__append_1 = -DHAVE_PCAP=1
 @HAVE_SELINUX_TRUE@am__append_2 = -DHAVE_SELINUX=1
-@IS_WINDOWS_TRUE@am__append_3 = -I$(abs_srcdir)/win32/includes
-@IS_WINDOWS_TRUE@am__append_4 = $(wpcap_IMP)
-@IS_WINDOWS_TRUE@am__append_5 = $(wpcap_DEF)
-@IS_WINDOWS_TRUE@am__append_6 = $(wpcap_IMP)
-@IS_WINDOWS_TRUE@am__append_7 = $(wpcap_DEF)
+@HAVE_ICMPFILTER_TRUE@am__append_3 = -DHAVE_ICMPFILTER=1
+@HAVE_ARC4RANDOM_TRUE@am__append_4 = -DHAVE_ARC4RANDOM=1
+@HAVE_ARC4RANDOM_FALSE@@HAVE_RANDOM_TRUE@am__append_5 = -DHAVE_RANDOM=1
+@IS_WINDOWS_TRUE@am__append_6 = -I$(abs_srcdir)/win32/includes
+@IS_WINDOWS_TRUE@am__append_7 = $(wpcap_IMP)
+@IS_WINDOWS_TRUE@am__append_8 = $(wpcap_DEF)
+@IS_WINDOWS_TRUE@am__append_9 = $(wpcap_IMP)
+@IS_WINDOWS_TRUE@am__append_10 = $(wpcap_DEF)
 subdir = src
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps = $(top_srcdir)/configure.ac
@@ -118,7 +121,7 @@ am_ptunnel_ng_OBJECTS = ptunnel_ng-md5.$(OBJEXT) \
 	ptunnel_ng-pdesc.$(OBJEXT) ptunnel_ng-ptunnel.$(OBJEXT) \
 	$(am__objects_2)
 ptunnel_ng_OBJECTS = $(am_ptunnel_ng_OBJECTS)
-ptunnel_ng_DEPENDENCIES = $(am__append_4)
+ptunnel_ng_DEPENDENCIES = $(am__append_7)
 ptunnel_ng_LINK = $(CCLD) $(ptunnel_ng_CFLAGS) $(CFLAGS) $(AM_LDFLAGS) \
 	$(LDFLAGS) -o $@
 AM_V_P = $(am__v_P_@AM_V@)
@@ -312,12 +315,13 @@ top_builddir = @top_builddir@
 top_srcdir = @top_srcdir@
 man8_MANS = ptunnel-ng.8
 ptunnel_ng_CFLAGS = -Wall $(am__append_1) $(am__append_2) \
-	$(am__append_3)
-ptunnel_ng_LDADD = $(am__append_4)
-CLEANFILES = $(am__append_6)
-EXTTRA_DIST = $(am__append_7)
+	$(am__append_3) $(am__append_4) $(am__append_5) \
+	$(am__append_6)
+ptunnel_ng_LDADD = $(am__append_7)
+CLEANFILES = $(am__append_9)
+EXTTRA_DIST = $(am__append_10)
 ptunnel_ng_SOURCES = md5.c challenge.c options.c utils.c pkt.c pdesc.c \
-	ptunnel.c $(am__append_5)
+	ptunnel.c $(am__append_8)
 @IS_WINDOWS_TRUE@wpcap_DEF = $(abs_srcdir)/win32/WPCAP.DEF
 @IS_WINDOWS_TRUE@wpcap_IMP = $(abs_srcdir)/win32/libwpcap_implib.a
 all: config.h
diff --git a/src/challenge.c b/src/challenge.c
index 24a13f7..f269313 100644
--- a/src/challenge.c
+++ b/src/challenge.c
@@ -5,7 +5,7 @@
  * Copyright (c) 2004-2011, Daniel Stoedle <daniels@cs.uit.no>,
  * Yellow Lemon Software. All rights reserved.
  *
- * Copyright (c) 2017 Toni Uhlig <matzeton@googlemail.com>
+ * Copyright (c) 2017-2019, Toni Uhlig <matzeton@googlemail.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -50,6 +50,7 @@
 #include "challenge.h"
 #include "options.h"
 #include "md5.h"
+#include "utils.h"
 
 /* generate_challenge: Generates a random challenge, incorporating the current
  * local timestamp to avoid replay attacks.
@@ -62,9 +63,9 @@ challenge_t* generate_challenge(void) {
 	c = (challenge_t *) calloc(1, sizeof(challenge_t));
 	gettimeofday(&tt, 0);
 	c->sec      = tt.tv_sec;
-	c->usec_rnd = tt.tv_usec + rand();
+	c->usec_rnd = tt.tv_usec + pt_random();
 	for (i=0;i<6;i++)
-		c->random[i] = rand();
+		c->random[i] = pt_random();
 
 	return c;
 }
diff --git a/src/challenge.h b/src/challenge.h
index 035a97e..18495cf 100644
--- a/src/challenge.h
+++ b/src/challenge.h
@@ -5,7 +5,7 @@
  * Copyright (c) 2004-2011, Daniel Stoedle <daniels@cs.uit.no>,
  * Yellow Lemon Software. All rights reserved.
  *
- * Copyright (c) 2017 Toni Uhlig <matzeton@googlemail.com>
+ * Copyright (c) 2017-2019, Toni Uhlig <matzeton@googlemail.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/src/config.h.in b/src/config.h.in
index 609856e..0cd059a 100644
--- a/src/config.h.in
+++ b/src/config.h.in
@@ -1,11 +1,17 @@
 /* src/config.h.in.  Generated from configure.ac by autoheader.  */
 
+/* Define to 1 if you have the `arc4random' function. */
+#undef HAVE_ARC4RANDOM
+
 /* Define to 1 if you have the <arpa/inet.h> header file. */
 #undef HAVE_ARPA_INET_H
 
 /* Define to 1 if you have the <assert.h> header file. */
 #undef HAVE_ASSERT_H
 
+/* Define to 1 if you have the <bsd/stdlib.h> header file. */
+#undef HAVE_BSD_STDLIB_H
+
 /* Define to 1 if you have the `calloc' function. */
 #undef HAVE_CALLOC
 
@@ -111,6 +117,9 @@
 /* Define to 1 if you have the <pwd.h> header file. */
 #undef HAVE_PWD_H
 
+/* Define to 1 if you have the `random' function. */
+#undef HAVE_RANDOM
+
 /* Define to 1 if you have the <selinux/selinux.h> header file. */
 #undef HAVE_SELINUX_SELINUX_H
 
@@ -123,6 +132,9 @@
 /* Define to 1 if you have the `sprintf' function. */
 #undef HAVE_SPRINTF
 
+/* Define to 1 if you have the `srandom' function. */
+#undef HAVE_SRANDOM
+
 /* Define to 1 if you have the <stdarg.h> header file. */
 #undef HAVE_STDARG_H
 
@@ -177,6 +189,9 @@
 /* Define to 1 if you have the <sys/unistd.h> header file. */
 #undef HAVE_SYS_UNISTD_H
 
+/* Define to 1 if you have the `timespec_get' function. */
+#undef HAVE_TIMESPEC_GET
+
 /* Define to 1 if you have the <time.h> header file. */
 #undef HAVE_TIME_H
 
diff --git a/src/options.c b/src/options.c
index beecd39..4ae434f 100644
--- a/src/options.c
+++ b/src/options.c
@@ -2,7 +2,7 @@
  * options.c
  * ptunnel is licensed under the BSD license:
  *
- * Copyright (c) 2017 Toni Uhlig <matzeton@googlemail.com>
+ * Copyright (c) 2017-2019, Toni Uhlig <matzeton@googlemail.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/src/options.h b/src/options.h
index 3c42a19..176620a 100644
--- a/src/options.h
+++ b/src/options.h
@@ -2,7 +2,7 @@
  * options.h
  * ptunnel is licensed under the BSD license:
  *
- * Copyright (c) 2017 Toni Uhlig <matzeton@googlemail.com>
+ * Copyright (c) 2017-2019, Toni Uhlig <matzeton@googlemail.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/src/pconfig.h b/src/pconfig.h
index c85df14..6be141e 100644
--- a/src/pconfig.h
+++ b/src/pconfig.h
@@ -5,7 +5,7 @@
  * Copyright (c) 2004-2011, Daniel Stoedle <daniels@cs.uit.no>,
  * Yellow Lemon Software. All rights reserved.
  *
- * Copyright (c) 2017 Toni Uhlig <matzeton@googlemail.com>
+ * Copyright (c) 2017-2019, Toni Uhlig <matzeton@googlemail.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/src/pdesc.c b/src/pdesc.c
index 906f35c..51fa3ab 100644
--- a/src/pdesc.c
+++ b/src/pdesc.c
@@ -5,7 +5,7 @@
  * Copyright (c) 2004-2011, Daniel Stoedle <daniels@cs.uit.no>,
  * Yellow Lemon Software. All rights reserved.
  *
- * Copyright (c) 2017 Toni Uhlig <matzeton@googlemail.com>
+ * Copyright (c) 2017-2019, Toni Uhlig <matzeton@googlemail.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -56,7 +56,7 @@
  * the descriptor chain. If the sock argument is 0, the function will establish
  * a TCP connection to the ip and port given by dst_ip, dst_port.
  */
-proxy_desc_t* create_and_insert_proxy_desc(uint16_t id_no, uint16_t icmp_id,
+proxy_desc_t *create_and_insert_proxy_desc(uint16_t id_no, uint16_t icmp_id,
                                            int sock, struct sockaddr_in *addr,
 			                               uint32_t dst_ip, uint32_t dst_port,
                                            uint32_t init_state, uint32_t type) {
diff --git a/src/pdesc.h b/src/pdesc.h
index 35147db..d0767aa 100644
--- a/src/pdesc.h
+++ b/src/pdesc.h
@@ -5,7 +5,7 @@
  * Copyright (c) 2004-2011, Daniel Stoedle <daniels@cs.uit.no>,
  * Yellow Lemon Software. All rights reserved.
  *
- * Copyright (c) 2017 Toni Uhlig <matzeton@googlemail.com>
+ * Copyright (c) 2017-2019, Toni Uhlig <matzeton@googlemail.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/src/pkt.c b/src/pkt.c
index 869cf51..d446ffd 100644
--- a/src/pkt.c
+++ b/src/pkt.c
@@ -5,7 +5,7 @@
  * Copyright (c) 2004-2011, Daniel Stoedle <daniels@cs.uit.no>,
  * Yellow Lemon Software. All rights reserved.
  *
- * Copyright (c) 2017 Toni Uhlig <matzeton@googlemail.com>
+ * Copyright (c) 2017-2019, Toni Uhlig <matzeton@googlemail.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -124,6 +124,10 @@ void handle_packet(char *buf, unsigned bytes, int is_pcap, struct sockaddr_in *a
   
 			pkt_flag        = pt_pkt->state & kFlag_mask;
 			pt_pkt->state   &= ~kFlag_mask;
+			if (pt_pkt->state > (kNum_proto_types-1)) {
+				pt_log(kLog_error, "Dropping packet with invalid state.\n");
+				return;
+			}
 			pt_log(kLog_sendrecv, "Recv: %d [%d] bytes "
 			                      "[seq = %d] [type = %s] "
 			                      "[ack = %d] [icmp = %d] "
@@ -166,10 +170,15 @@ void handle_packet(char *buf, unsigned bytes, int is_pcap, struct sockaddr_in *a
 						else
 							init_state  = kProto_data;
 
-						cur = create_and_insert_proxy_desc(pt_pkt->id_no, pkt->identifier, 0,
+						cur = (proxy_desc_t *) create_and_insert_proxy_desc(pt_pkt->id_no, pkt->identifier, 0,
 						                                   addr, pt_pkt->dst_ip,
 						                                   ntohl(pt_pkt->dst_port),
 						                                   init_state, kProxy_flag);
+					       if (!cur) {
+							/* if failed, abort. Logging is done in create_insert_proxy_desc */
+							pt_log(kLog_error, "Failed to create proxy descriptor!\n");
+							return;
+						}
 						if (init_state == kProto_authenticate) {
 							pt_log(kLog_debug, "Sending authentication challenge..\n");
 							/* Send challenge */
@@ -189,7 +198,9 @@ void handle_packet(char *buf, unsigned bytes, int is_pcap, struct sockaddr_in *a
 						return;
 					}
 					else
-						pt_log(kLog_error, "Dropping duplicate proxy session request.\n");
+						pt_log(kLog_error, "Dropping duplicate proxy session request "
+						                   "with ID %d and seq %d.\n",
+						                   pt_pkt->id_no, pt_pkt->seq_no);
 				}
 				else if (cur && pt_pkt->state == kProto_authenticate) {
 					/* Sanity check packet length, and make sure it matches what we expect */
diff --git a/src/pkt.h b/src/pkt.h
index 9668d97..338bc65 100644
--- a/src/pkt.h
+++ b/src/pkt.h
@@ -5,7 +5,7 @@
  * Copyright (c) 2004-2011, Daniel Stoedle <daniels@cs.uit.no>,
  * Yellow Lemon Software. All rights reserved.
  *
- * Copyright (c) 2017 Toni Uhlig <matzeton@googlemail.com>
+ * Copyright (c) 2017-2019, Toni Uhlig <matzeton@googlemail.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/src/ptunnel.c b/src/ptunnel.c
index a4c5ae5..8fdf7a8 100644
--- a/src/ptunnel.c
+++ b/src/ptunnel.c
@@ -5,7 +5,7 @@
  * Copyright (c) 2004-2011, Daniel Stoedle <daniels@cs.uit.no>,
  * Yellow Lemon Software. All rights reserved.
  *
- * Copyright (c) 2017 Toni Uhlig <matzeton@googlemail.com>
+ * Copyright (c) 2017-2019, Toni Uhlig <matzeton@googlemail.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -62,7 +62,7 @@
 #define errno GetLastError()
 /** Local error string storage */
 static char errorstr[255];
-static char * print_last_windows_error()  {
+static char * print_last_windows_error() {
 	char last_errorstr[255];
 	DWORD last_error = GetLastError();
 
@@ -126,10 +126,6 @@ int main(int argc, char *argv[]) {
 	}
 #endif /* WIN32 */
 
-	/* Seed random generator; it'll be used in combination with a timestamp
-	 * when generating authentication challenges.
-	 */
-	srand(time(0));
 	memset(opts.password_digest, 0, kMD5_digest_size);
 
 	/* The seq_expiry_tbl is used to prevent the remote ends from prematurely
@@ -154,7 +150,7 @@ int main(int argc, char *argv[]) {
 #endif
 	pt_log(kLog_info, "Starting %s.\n", PACKAGE_STRING);
 	pt_log(kLog_info, "(c) 2004-2011 Daniel Stoedle, <daniels@cs.uit.no>\n");
-	pt_log(kLog_info, "(c) 2017      Toni Uhlig,     <matzeton@googlemail.com>\n");
+	pt_log(kLog_info, "(c) 2017-2019 Toni Uhlig,     <matzeton@googlemail.com>\n");
 #ifdef WIN32
 	pt_log(kLog_info, "Windows version by Mike Miller, <mike@mikeage.net>\n");
 #else
@@ -184,7 +180,7 @@ int main(int argc, char *argv[]) {
 	if (opts.chroot) {
 		pt_log(kLog_info, "Restricting file access to %s\n", opts.root_dir);
 		if (-1 == chdir(opts.root_dir) || -1 == chroot(opts.root_dir)) {
-			pt_log(kLog_error, "%s: %s\n", opts.root_dir, strerror(errno));
+			pt_log(kLog_error, "chdir/chroot `%s': %s\n", opts.root_dir, strerror(errno));
 			exit(1);
 		}
 	}
@@ -210,7 +206,7 @@ int main(int argc, char *argv[]) {
 					if (! freopen("/dev/null", "r", stdin) ||
 					    ! freopen("/dev/null", "w", stdout) ||
 					    ! freopen("/dev/null", "w", stderr))
-						pt_log(kLog_error, "freopen: %s\n", strerror(errno));
+						pt_log(kLog_error, "freopen `%s': %s\n", "/dev/null", strerror(errno));
 				}
 			}
 	}
@@ -323,7 +319,7 @@ void pt_forwarder(void) {
 				}
 			}
 			addr	= dest_addr;
-			rand_id	= (uint16_t)rand();
+			rand_id	= (uint16_t) pt_random();
 			create_and_insert_proxy_desc(rand_id, rand_id, new_sock, &addr, opts.given_dst_ip, opts.given_dst_port, kProxy_start, kUser_flag);
 			pthread_mutex_unlock(&num_threads_lock);
 		}
@@ -388,6 +384,9 @@ void* pt_proxy(void *args) {
 	in_addr_t          *adr;
 #endif
 	struct in_addr     in_addr;
+#ifdef HAVE_ICMPFILTER
+	struct icmp_filter filt;
+#endif
 
 	/* Start the thread, initialize protocol and ring states. */
 	pt_log(kLog_debug, "Starting ping proxy..\n");
@@ -403,13 +402,24 @@ void* pt_proxy(void *args) {
 		}
 	}
 	else {
-		if (opts.unprivileged) {
+		if (opts.unprivileged)
+		{
 			pt_log(kLog_debug, "Attempting to create unprivileged ICMP datagram socket..\n");
 			fwd_sock		= socket(AF_INET, SOCK_DGRAM, IPPROTO_ICMP);
-		}
-		else {
+		} else {
 			pt_log(kLog_debug, "Attempting to create privileged ICMP raw socket..\n");
 			fwd_sock		= socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
+#ifdef HAVE_ICMPFILTER
+			if (opts.mode == kMode_forward)
+				filt.data	= ~(1<<ICMP_ECHOREPLY);
+			else
+				filt.data	= ~(1<<ICMP_ECHO);
+			if (fwd_sock >= 0 &&
+			    setsockopt(fwd_sock, SOL_RAW, ICMP_FILTER, &filt, sizeof filt) == -1)
+			{
+				pt_log(kLog_error, "setockopt for ICMP_FILTER: %s\n", strerror(errno));
+			}
+#endif
 		}
 		if (fwd_sock < 0) {
 			pt_log(kLog_error, "Couldn't create %s socket: %s\n",
diff --git a/src/ptunnel.h b/src/ptunnel.h
index 7566f92..d93f997 100644
--- a/src/ptunnel.h
+++ b/src/ptunnel.h
@@ -45,6 +45,9 @@
 #define PING_TUNNEL_H 1
 
 #ifndef WIN32
+#ifdef HAVE_ICMPFILTER
+#include <linux/icmp.h>
+#endif
 #ifdef HAVE_SYS_UNISTD_H
 #include <sys/unistd.h>
 #endif
diff --git a/src/utils.c b/src/utils.c
index 66ed4c0..462d688 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -5,7 +5,7 @@
  * Copyright (c) 2004-2011, Daniel Stoedle <daniels@cs.uit.no>,
  * Yellow Lemon Software. All rights reserved.
  *
- * Copyright (c) 2017 Toni Uhlig <matzeton@googlemail.com>
+ * Copyright (c) 2017-2019, Toni Uhlig <matzeton@googlemail.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -43,8 +43,15 @@
  * Note that the source code is best viewed with tabs set to 4 spaces.
  */
 
+#include <stdio.h>
+#include <stdlib.h>
 #include <stdarg.h>
 #include <string.h>
+#include <time.h>
+#include <assert.h>
+#ifdef HAVE_ARC4RANDOM
+#include <bsd/stdlib.h>
+#endif
 
 #ifndef WIN32
 #include <syslog.h>
@@ -142,3 +149,23 @@ void print_hexstr(unsigned char *buf, size_t siz) {
 	free(out);
 }
 #endif
+
+int pt_random(void) {
+#ifdef HAVE_ARC4RANDOM
+	return arc4random();
+#else
+#ifdef HAVE_RANDOM
+#ifndef TIME_UTC
+#define TIME_UTC 1
+#endif
+	struct timespec ts;
+
+	assert(timespec_get(&ts, TIME_UTC));
+	srandom(ts.tv_nsec ^ ts.tv_sec);
+	return random();
+#else
+	srand(time(0));
+	return rand();
+#endif
+#endif
+}
diff --git a/src/utils.h b/src/utils.h
index 8afa45c..0796848 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -5,7 +5,7 @@
  * Copyright (c) 2004-2011, Daniel Stoedle <daniels@cs.uit.no>,
  * Yellow Lemon Software. All rights reserved.
  *
- * Copyright (c) 2017 Toni Uhlig <matzeton@googlemail.com>
+ * Copyright (c) 2017-2019, Toni Uhlig <matzeton@googlemail.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -60,4 +60,6 @@ int host_to_addr(const char *hostname, uint32_t *result);
 void print_hexstr(unsigned char *buf, size_t siz);
 #endif
 
+int pt_random(void);
+
 #endif