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authorAlberto Gonzalez Iniesta <agi@inittab.org>2017-05-11 14:20:52 +0200
committerAlberto Gonzalez Iniesta <agi@inittab.org>2017-05-11 14:20:52 +0200
commitde39933a5c67a449c4c31e4e8f0c1d2c218c8c6c (patch)
treeab0cde60215daea4e84cce2c003caaf84586806c /debian
parent39c2d4f2279614bae0c1debb25b12585e5e7c372 (diff)
Security fixes for sid. CVE-2017-7478 & CVE-2017-7479debian/2.4.0-5
Diffstat (limited to 'debian')
-rw-r--r--debian/changelog23
-rw-r--r--debian/patches/CVE-2017-7478.patch55
-rw-r--r--debian/patches/CVE-2017-7479-prereq.patch443
-rw-r--r--debian/patches/CVE-2017-7479.patch193
-rw-r--r--debian/patches/series4
-rw-r--r--debian/patches/wipe_tokens_on_de-auth.patch118
6 files changed, 836 insertions, 0 deletions
diff --git a/debian/changelog b/debian/changelog
index d22f5e7..0dbcb49 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,26 @@
+openvpn (2.4.0-5) unstable; urgency=high
+
+ * Change typo fix in command line help.
+ * SECURITY UPDATE: pre-authentication denial-of-service vulnerability
+ (both client and server) from a too-large control packet.
+ - debian/patches/CVE-2017-7478.patch: Do not assert on too-large
+ control packet
+ - CVE-2017-7478
+ * SECURITY UPDATE: authenticated remote DoS vulnerability due to
+ packet ID rollover
+ - debian/patches/CVE-2017-7479-prereq.patch: merge
+ packet_id_alloc_outgoing() into packet_id_write()
+ - debian/patches/CVE-2017-7479.patch: do not assert when packet ID
+ rollover occurs
+ - CVE-2017-7479
+ * SECURITY UPDATE: auth tokens left in memory after de-auth
+ - debian/patches/wipe_tokens_on_de-auth.patch: always wipe token
+ as soon as a TLS session is considered broken.
+ * Kudos to Steve Beattie <sbeattie@ubuntu.com> for doing all the
+ backporting work for this upload.
+
+ -- Alberto Gonzalez Iniesta <agi@inittab.org> Thu, 11 May 2017 14:15:21 +0200
+
openvpn (2.4.0-4) unstable; urgency=medium
* Add NEWS entries on possible 2.4 migration issues.
diff --git a/debian/patches/CVE-2017-7478.patch b/debian/patches/CVE-2017-7478.patch
new file mode 100644
index 0000000..e301cf1
--- /dev/null
+++ b/debian/patches/CVE-2017-7478.patch
@@ -0,0 +1,55 @@
+From be66408610a52f81c9c895a8973958ead55a4e57 Mon Sep 17 00:00:00 2001
+From: Steffan Karger <steffan.karger@fox-it.com>
+Date: Tue, 9 May 2017 15:40:25 +0300
+Subject: [PATCH] Don't assert out on receiving too-large control packets
+ (CVE-2017-xxx)
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Commit 3c1b19e0 changed the maximum size of accepted control channel
+packets. This was needed for crypto negotiation (which is needed for a
+nice transition to a new default cipher), but exposed a DoS
+vulnerability. The vulnerability was found during the OpenVPN 2.4 code
+audit by Quarkslab (commisioned by OSTIF).
+
+To fix the issue, we should not ASSERT() on external input (in this case
+the received packet size), but instead gracefully error out and drop the
+invalid packet.
+
+Signed-off-by: Steffan Karger <steffan.karger@fox-it.com>
+Signed-off-by: Samuli Seppänen <samuli@openvpn.net>
+
+CVE-2017-7478
+
+ Security
+ --------
+ - This release fixes a pre-authentication denial-of-service attack on both
+ clients and servers. By sending a too-large control packet, OpenVPN 2.4.0 or
+ 2.4.1 can be forced to hit an ASSERT() and stop the process. If
+ ``--tls-auth`` or ``--tls-crypt`` is used, only attackers that have the
+ ``--tls-auth`` or ``--tls-crypt`` key can mount an attack. (CVE-2017-xxx)
+
+---
+ Changes.rst | 8 ++++++++
+ src/openvpn/ssl.c | 7 ++++++-
+ 2 files changed, 14 insertions(+), 1 deletion(-)
+
+Index: openvpn-2.4.0/src/openvpn/ssl.c
+===================================================================
+--- openvpn-2.4.0.orig/src/openvpn/ssl.c
++++ openvpn-2.4.0/src/openvpn/ssl.c
+@@ -3708,7 +3708,12 @@ tls_pre_decrypt(struct tls_multi *multi,
+ /* Save incoming ciphertext packet to reliable buffer */
+ struct buffer *in = reliable_get_buf(ks->rec_reliable);
+ ASSERT(in);
+- ASSERT(buf_copy(in, buf));
++ if(!buf_copy(in, buf))
++ {
++ msg(D_MULTI_DROPPED,
++ "Incoming control channel packet too big, dropping.");
++ goto error;
++ }
+ reliable_mark_active_incoming(ks->rec_reliable, in, id, op);
+ }
+
diff --git a/debian/patches/CVE-2017-7479-prereq.patch b/debian/patches/CVE-2017-7479-prereq.patch
new file mode 100644
index 0000000..e3c94d7
--- /dev/null
+++ b/debian/patches/CVE-2017-7479-prereq.patch
@@ -0,0 +1,443 @@
+From a87e1431baccd49a9344cfc63ab7446c4317fa2f Mon Sep 17 00:00:00 2001
+From: Steffan Karger <steffan.karger@fox-it.com>
+Date: Fri, 5 May 2017 19:44:51 +0200
+Subject: [PATCH] cleanup: merge packet_id_alloc_outgoing() into
+ packet_id_write()
+
+The functions packet_id_alloc_outgoing() and packet_id_write() were
+always called in tandem. Instead of forcing the caller to allocate a
+packet_id_net to do so, merge the two functions. This simplifies the API
+and reduces the chance on mistakes in the future.
+
+This patch adds unit tests to verify the behaviour of packet_id_write().
+Verifying that we assert out correctly required the change to mock_msg.c.
+
+Signed-off-by: Steffan Karger <steffan.karger@fox-it.com>
+Acked-by: Gert Doering <gert@greenie.muc.de>
+Acked-by: David Sommerseth <davids@openvpn.net>
+Message-Id: <1494006291-3522-1-git-send-email-steffan.karger@fox-it.com>
+URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg14541.html
+Signed-off-by: Gert Doering <gert@greenie.muc.de>
+
+[prerequisite for CVE-2017-7479. Adjusted to apply to 2.4.0 release -- sbeattie]
+
+---
+ src/openvpn/crypto.c | 20 ++--
+ src/openvpn/packet_id.c | 24 ++++-
+ src/openvpn/packet_id.h | 35 +++----
+ src/openvpn/tls_crypt.c | 6 +-
+ tests/unit_tests/openvpn/Makefile.am | 13 ++-
+ tests/unit_tests/openvpn/mock_msg.c | 15 ++-
+ tests/unit_tests/openvpn/test_packet_id.c | 168 ++++++++++++++++++++++++++++++
+ 7 files changed, 228 insertions(+), 53 deletions(-)
+ create mode 100644 tests/unit_tests/openvpn/test_packet_id.c
+
+Index: openvpn-2.4.0/src/openvpn/crypto.c
+===================================================================
+--- openvpn-2.4.0.orig/src/openvpn/crypto.c
++++ openvpn-2.4.0/src/openvpn/crypto.c
+@@ -85,7 +85,6 @@ openvpn_encrypt_aead(struct buffer *buf,
+ /* Prepare IV */
+ {
+ struct buffer iv_buffer;
+- struct packet_id_net pin;
+ uint8_t iv[OPENVPN_MAX_IV_LENGTH] = {0};
+ const int iv_len = cipher_ctx_iv_length(ctx->cipher);
+
+@@ -94,8 +93,7 @@ openvpn_encrypt_aead(struct buffer *buf,
+ buf_set_write(&iv_buffer, iv, iv_len);
+
+ /* IV starts with packet id to make the IV unique for packet */
+- packet_id_alloc_outgoing(&opt->packet_id.send, &pin, false);
+- ASSERT(packet_id_write(&pin, &iv_buffer, false, false));
++ ASSERT(packet_id_write(&opt->packet_id.send, &iv_buffer, false, false));
+
+ /* Remainder of IV consists of implicit part (unique per session) */
+ ASSERT(buf_write(&iv_buffer, ctx->implicit_iv, ctx->implicit_iv_len));
+@@ -198,23 +196,21 @@ openvpn_encrypt_v1(struct buffer *buf, s
+ /* Put packet ID in plaintext buffer */
+ if (packet_id_initialized(&opt->packet_id))
+ {
+- struct packet_id_net pin;
+- packet_id_alloc_outgoing(&opt->packet_id.send, &pin, BOOL_CAST(opt->flags & CO_PACKET_ID_LONG_FORM));
+- ASSERT(packet_id_write(&pin, buf, BOOL_CAST(opt->flags & CO_PACKET_ID_LONG_FORM), true));
++ ASSERT(packet_id_write(&opt->packet_id.send, buf,
++ opt->flags & CO_PACKET_ID_LONG_FORM,
++ true));
+ }
+ }
+ else if (cipher_kt_mode_ofb_cfb(cipher_kt))
+ {
+- struct packet_id_net pin;
+ struct buffer b;
+
+ /* IV and packet-ID required for this mode. */
+ ASSERT(opt->flags & CO_USE_IV);
+ ASSERT(packet_id_initialized(&opt->packet_id));
+
+- packet_id_alloc_outgoing(&opt->packet_id.send, &pin, true);
+ buf_set_write(&b, iv_buf, iv_size);
+- ASSERT(packet_id_write(&pin, &b, true, false));
++ ASSERT(packet_id_write(&opt->packet_id.send, &b, true, false));
+ }
+ else /* We only support CBC, CFB, or OFB modes right now */
+ {
+@@ -264,9 +260,9 @@ openvpn_encrypt_v1(struct buffer *buf, s
+ {
+ if (packet_id_initialized(&opt->packet_id))
+ {
+- struct packet_id_net pin;
+- packet_id_alloc_outgoing(&opt->packet_id.send, &pin, BOOL_CAST(opt->flags & CO_PACKET_ID_LONG_FORM));
+- ASSERT(packet_id_write(&pin, buf, BOOL_CAST(opt->flags & CO_PACKET_ID_LONG_FORM), true));
++ ASSERT(packet_id_write(&opt->packet_id.send, buf,
++ BOOL_CAST(opt->flags & CO_PACKET_ID_LONG_FORM),
++ true));
+ }
+ if (ctx->hmac)
+ {
+Index: openvpn-2.4.0/src/openvpn/packet_id.c
+===================================================================
+--- openvpn-2.4.0.orig/src/openvpn/packet_id.c
++++ openvpn-2.4.0/src/openvpn/packet_id.c
+@@ -325,12 +325,30 @@ packet_id_read(struct packet_id_net *pin
+ return true;
+ }
+
++static void
++packet_id_send_update(struct packet_id_send *p, bool long_form)
++{
++ if (!p->time)
++ {
++ p->time = now;
++ }
++ p->id++;
++ if (!p->id)
++ {
++ ASSERT(long_form);
++ p->time = now;
++ p->id = 1;
++ }
++}
++
+ bool
+-packet_id_write(const struct packet_id_net *pin, struct buffer *buf, bool long_form, bool prepend)
++packet_id_write(struct packet_id_send *p, struct buffer *buf, bool long_form,
++ bool prepend)
+ {
+- packet_id_type net_id = htonpid(pin->id);
+- net_time_t net_time = htontime(pin->time);
++ packet_id_send_update(p, long_form);
+
++ const packet_id_type net_id = htonpid(p->id);
++ const net_time_t net_time = htontime(p->time);
+ if (prepend)
+ {
+ if (long_form)
+Index: openvpn-2.4.0/src/openvpn/packet_id.h
+===================================================================
+--- openvpn-2.4.0.orig/src/openvpn/packet_id.h
++++ openvpn-2.4.0/src/openvpn/packet_id.h
+@@ -254,7 +254,18 @@ const char *packet_id_persist_print(cons
+
+ bool packet_id_read(struct packet_id_net *pin, struct buffer *buf, bool long_form);
+
+-bool packet_id_write(const struct packet_id_net *pin, struct buffer *buf, bool long_form, bool prepend);
++/**
++ * Write a packet ID to buf, and update the packet ID state.
++ *
++ * @param p Packet ID state.
++ * @param buf Buffer to write the packet ID too
++ * @param long_form If true, also update and write time_t to buf
++ * @param prepend If true, prepend to buffer, otherwise apppend.
++ *
++ * @return true if successful, false otherwise.
++ */
++bool packet_id_write(struct packet_id_send *p, struct buffer *buf,
++ bool long_form, bool prepend);
+
+ /*
+ * Inline functions.
+@@ -304,28 +315,6 @@ packet_id_close_to_wrapping(const struct
+ return p->id >= PACKET_ID_WRAP_TRIGGER;
+ }
+
+-/*
+- * Allocate an outgoing packet id.
+- * Sequence number ranges from 1 to 2^32-1.
+- * In long_form, a time_t is added as well.
+- */
+-static inline void
+-packet_id_alloc_outgoing(struct packet_id_send *p, struct packet_id_net *pin, bool long_form)
+-{
+- if (!p->time)
+- {
+- p->time = now;
+- }
+- pin->id = ++p->id;
+- if (!pin->id)
+- {
+- ASSERT(long_form);
+- p->time = now;
+- pin->id = p->id = 1;
+- }
+- pin->time = p->time;
+-}
+-
+ static inline bool
+ check_timestamp_delta(time_t remote, unsigned int max_delta)
+ {
+Index: openvpn-2.4.0/src/openvpn/tls_crypt.c
+===================================================================
+--- openvpn-2.4.0.orig/src/openvpn/tls_crypt.c
++++ openvpn-2.4.0/src/openvpn/tls_crypt.c
+@@ -95,11 +95,7 @@ tls_crypt_wrap(const struct buffer *src,
+ format_hex(BPTR(src), BLEN(src), 80, &gc));
+
+ /* Get packet ID */
+- {
+- struct packet_id_net pin;
+- packet_id_alloc_outgoing(&opt->packet_id.send, &pin, true);
+- packet_id_write(&pin, dst, true, false);
+- }
++ ASSERT(packet_id_write(&opt->packet_id.send, dst, true, false));
+
+ dmsg(D_PACKET_CONTENT, "TLS-CRYPT WRAP AD: %s",
+ format_hex(BPTR(dst), BLEN(dst), 0, &gc));
+Index: openvpn-2.4.0/tests/unit_tests/openvpn/Makefile.am
+===================================================================
+--- openvpn-2.4.0.orig/tests/unit_tests/openvpn/Makefile.am
++++ openvpn-2.4.0/tests/unit_tests/openvpn/Makefile.am
+@@ -1,6 +1,6 @@
+ AUTOMAKE_OPTIONS = foreign
+
+-check_PROGRAMS = argv_testdriver buffer_testdriver
++check_PROGRAMS = argv_testdriver buffer_testdriver packet_id_testdriver
+
+ if ENABLE_CRYPTO
+ check_PROGRAMS += tls_crypt_testdriver
+@@ -27,6 +27,17 @@ buffer_testdriver_SOURCES = test_buffer.
+ $(openvpn_srcdir)/buffer.c \
+ $(openvpn_srcdir)/platform.c
+
++packet_id_testdriver_CFLAGS = @TEST_CFLAGS@ \
++ -I$(openvpn_includedir) -I$(compat_srcdir) -I$(openvpn_srcdir) \
++ $(OPTIONAL_CRYPTO_CFLAGS)
++packet_id_testdriver_LDFLAGS = @TEST_LDFLAGS@ \
++ $(OPTIONAL_CRYPTO_LIBS)
++packet_id_testdriver_SOURCES = test_packet_id.c mock_msg.c \
++ $(openvpn_srcdir)/buffer.c \
++ $(openvpn_srcdir)/otime.c \
++ $(openvpn_srcdir)/packet_id.c \
++ $(openvpn_srcdir)/platform.c
++
+ tls_crypt_testdriver_CFLAGS = @TEST_CFLAGS@ \
+ -I$(openvpn_includedir) -I$(compat_srcdir) -I$(openvpn_srcdir) \
+ $(OPTIONAL_CRYPTO_CFLAGS)
+Index: openvpn-2.4.0/tests/unit_tests/openvpn/mock_msg.c
+===================================================================
+--- openvpn-2.4.0.orig/tests/unit_tests/openvpn/mock_msg.c
++++ openvpn-2.4.0/tests/unit_tests/openvpn/mock_msg.c
+@@ -29,9 +29,12 @@
+ #endif
+
+ #include <stdarg.h>
+-#include <stdbool.h>
++#include <stddef.h>
+ #include <stdio.h>
+ #include <stdlib.h>
++#include <setjmp.h>
++#include <cmocka.h>
++
+
+ #include "errlevel.h"
+ #include "error.h"
+@@ -70,14 +73,8 @@ x_msg(const unsigned int flags, const ch
+ void
+ assert_failed(const char *filename, int line, const char *condition)
+ {
+- if (condition)
+- {
+- printf("Assertion failed at %s:%d (%s)", filename, line, condition);
+- }
+- else
+- {
+- printf("Assertion failed at %s:%d", filename, line);
+- }
++ mock_assert(false, condition ? condition : "", filename, line);
++ /* Keep compiler happy. Should not happen, mock_assert() does not return */
+ exit(1);
+ }
+
+Index: openvpn-2.4.0/tests/unit_tests/openvpn/test_packet_id.c
+===================================================================
+--- /dev/null
++++ openvpn-2.4.0/tests/unit_tests/openvpn/test_packet_id.c
+@@ -0,0 +1,168 @@
++/*
++ * OpenVPN -- An application to securely tunnel IP networks
++ * over a single UDP port, with support for SSL/TLS-based
++ * session authentication and key exchange,
++ * packet encryption, packet authentication, and
++ * packet compression.
++ *
++ * Copyright (C) 2016 Fox Crypto B.V. <openvpn@fox-it.com>
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2
++ * as published by the Free Software Foundation.
++ *
++ * This program is distributed in the hope that it will be useful,
++ * but WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
++ * GNU General Public License for more details.
++ *
++ * You should have received a copy of the GNU General Public License
++ * along with this program (see the file COPYING included with this
++ * distribution); if not, write to the Free Software Foundation, Inc.,
++ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
++ */
++
++#ifdef HAVE_CONFIG_H
++#include "config.h"
++#elif defined(_MSC_VER)
++#include "config-msvc.h"
++#endif
++
++#include "syshead.h"
++
++#include <stdarg.h>
++#include <stddef.h>
++#include <setjmp.h>
++#include <cmocka.h>
++
++#include "packet_id.h"
++
++#include "mock_msg.h"
++
++struct test_packet_id_write_data {
++ struct {
++ uint32_t buf_id;
++ uint32_t buf_time;
++ } test_buf_data;
++ struct buffer test_buf;
++ struct packet_id_send pis;
++};
++
++static int
++test_packet_id_write_setup(void **state) {
++ struct test_packet_id_write_data *data =
++ calloc(1, sizeof(struct test_packet_id_write_data));
++
++ if (!data)
++ {
++ return -1;
++ }
++
++ data->test_buf.data = (void *) &data->test_buf_data;
++ data->test_buf.capacity = sizeof(data->test_buf_data);
++
++ *state = data;
++ return 0;
++}
++
++static int
++test_packet_id_write_teardown(void **state) {
++ free(*state);
++ return 0;
++}
++
++static void
++test_packet_id_write_short(void **state)
++{
++ struct test_packet_id_write_data *data = *state;
++
++ now = 5010;
++ assert_true(packet_id_write(&data->pis, &data->test_buf, false, false));
++ assert_true(data->pis.id == 1);
++ assert_true(data->test_buf_data.buf_id == htonl(1));
++ assert_true(data->test_buf_data.buf_time == 0);
++}
++
++static void
++test_packet_id_write_long(void **state)
++{
++ struct test_packet_id_write_data *data = *state;
++
++ now = 5010;
++ assert_true(packet_id_write(&data->pis, &data->test_buf, true, false));
++ assert(data->pis.id == 1);
++ assert(data->pis.time == now);
++ assert_true(data->test_buf_data.buf_id == htonl(1));
++ assert_true(data->test_buf_data.buf_time == htonl(now));
++}
++
++static void
++test_packet_id_write_short_prepend(void **state)
++{
++ struct test_packet_id_write_data *data = *state;
++
++ data->test_buf.offset = sizeof(packet_id_type);
++ now = 5010;
++ assert_true(packet_id_write(&data->pis, &data->test_buf, false, true));
++ assert_true(data->pis.id == 1);
++ assert_true(data->test_buf_data.buf_id == htonl(1));
++ assert_true(data->test_buf_data.buf_time == 0);
++}
++
++static void
++test_packet_id_write_long_prepend(void **state)
++{
++ struct test_packet_id_write_data *data = *state;
++
++ data->test_buf.offset = sizeof(data->test_buf_data);
++ now = 5010;
++ assert_true(packet_id_write(&data->pis, &data->test_buf, true, true));
++ assert(data->pis.id == 1);
++ assert(data->pis.time == now);
++ assert_true(data->test_buf_data.buf_id == htonl(1));
++ assert_true(data->test_buf_data.buf_time == htonl(now));
++}
++
++static void
++test_packet_id_write_short_wrap(void **state)
++{
++ struct test_packet_id_write_data *data = *state;
++
++ data->pis.id = ~0;
++ expect_assert_failure(
++ packet_id_write(&data->pis, &data->test_buf, false, false));
++}
++
++static void
++test_packet_id_write_long_wrap(void **state)
++{
++ struct test_packet_id_write_data *data = *state;
++
++ data->pis.id = ~0;
++ now = 5010;
++ assert_true(packet_id_write(&data->pis, &data->test_buf, true, false));
++ assert(data->pis.id == 1);
++ assert(data->pis.time == now);
++ assert_true(data->test_buf_data.buf_id == htonl(1));
++ assert_true(data->test_buf_data.buf_time == htonl(now));
++}
++
++int
++main(void) {
++ const struct CMUnitTest tests[] = {
++ cmocka_unit_test_setup_teardown(test_packet_id_write_short,
++ test_packet_id_write_setup, test_packet_id_write_teardown),
++ cmocka_unit_test_setup_teardown(test_packet_id_write_long,
++ test_packet_id_write_setup, test_packet_id_write_teardown),
++ cmocka_unit_test_setup_teardown(test_packet_id_write_short_prepend,
++ test_packet_id_write_setup, test_packet_id_write_teardown),
++ cmocka_unit_test_setup_teardown(test_packet_id_write_long_prepend,
++ test_packet_id_write_setup, test_packet_id_write_teardown),
++ cmocka_unit_test_setup_teardown(test_packet_id_write_short_wrap,
++ test_packet_id_write_setup, test_packet_id_write_teardown),
++ cmocka_unit_test_setup_teardown(test_packet_id_write_long_wrap,
++ test_packet_id_write_setup, test_packet_id_write_teardown),
++ };
++
++ return cmocka_run_group_tests_name("packet_id tests", tests, NULL, NULL);
++}
diff --git a/debian/patches/CVE-2017-7479.patch b/debian/patches/CVE-2017-7479.patch
new file mode 100644
index 0000000..9f75d31
--- /dev/null
+++ b/debian/patches/CVE-2017-7479.patch
@@ -0,0 +1,193 @@
+From ac08b27cfa693d9be592bb2597c260635aee9e68 Mon Sep 17 00:00:00 2001
+From: Steffan Karger <steffan.karger@fox-it.com>
+Date: Tue, 25 Apr 2017 10:00:44 +0200
+Subject: [PATCH 2/2] Drop packets instead of asserting out if packet id rolls
+ over
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Previously, if a mode was selected where packet ids are not allowed to roll
+over, but renegotiation does not succeed for some reason (e.g. no password
+entered in time, certificate expired or a malicious peer that refuses the
+renegotiaion on purpose) we would continue to use the old keys. Until the
+packet ID would roll over and we would ASSERT() out.
+
+Given that this can be triggered on purpose by an authenticated peer, this
+is a fix for an authenticated remote DoS vulnerability. An attack is
+rather inefficient though; a peer would need to get us to send 2^32
+packets (min-size packet is IP+UDP+OPCODE+PID+TAG (no payload), results in
+(20+8+1+4+16)×2^32 bytes, or approx. 196 GB).
+
+Signed-off-by: Steffan Karger <steffan.karger@fox-it.com>
+
+CVE-2017-7479
+
+---
+ src/openvpn/crypto.c | 25 ++++++++++++++++---------
+ src/openvpn/packet_id.c | 22 ++++++++++++++++------
+ src/openvpn/packet_id.h | 1 +
+ src/openvpn/tls_crypt.c | 6 +++++-
+ tests/unit_tests/openvpn/test_packet_id.c | 11 +++++++++--
+ 5 files changed, 47 insertions(+), 18 deletions(-)
+
+Index: openvpn-2.4.0/src/openvpn/crypto.c
+===================================================================
+--- openvpn-2.4.0.orig/src/openvpn/crypto.c
++++ openvpn-2.4.0/src/openvpn/crypto.c
+@@ -93,7 +93,11 @@ openvpn_encrypt_aead(struct buffer *buf,
+ buf_set_write(&iv_buffer, iv, iv_len);
+
+ /* IV starts with packet id to make the IV unique for packet */
+- ASSERT(packet_id_write(&opt->packet_id.send, &iv_buffer, false, false));
++ if (!packet_id_write(&opt->packet_id.send, &iv_buffer, false, false))
++ {
++ msg(D_CRYPT_ERRORS, "ENCRYPT ERROR: packet ID roll over");
++ goto err;
++ }
+
+ /* Remainder of IV consists of implicit part (unique per session) */
+ ASSERT(buf_write(&iv_buffer, ctx->implicit_iv, ctx->implicit_iv_len));
+@@ -194,11 +198,13 @@ openvpn_encrypt_v1(struct buffer *buf, s
+ }
+
+ /* Put packet ID in plaintext buffer */
+- if (packet_id_initialized(&opt->packet_id))
++ if (packet_id_initialized(&opt->packet_id)
++ && !packet_id_write(&opt->packet_id.send, buf,
++ opt->flags & CO_PACKET_ID_LONG_FORM,
++ true))
+ {
+- ASSERT(packet_id_write(&opt->packet_id.send, buf,
+- opt->flags & CO_PACKET_ID_LONG_FORM,
+- true));
++ msg(D_CRYPT_ERRORS, "ENCRYPT ERROR: packet ID roll over");
++ goto err;
+ }
+ }
+ else if (cipher_kt_mode_ofb_cfb(cipher_kt))
+@@ -258,11 +264,12 @@ openvpn_encrypt_v1(struct buffer *buf, s
+ }
+ else /* No Encryption */
+ {
+- if (packet_id_initialized(&opt->packet_id))
++ if (packet_id_initialized(&opt->packet_id)
++ && !packet_id_write(&opt->packet_id.send, buf,
++ opt->flags & CO_PACKET_ID_LONG_FORM, true))
+ {
+- ASSERT(packet_id_write(&opt->packet_id.send, buf,
+- BOOL_CAST(opt->flags & CO_PACKET_ID_LONG_FORM),
+- true));
++ msg(D_CRYPT_ERRORS, "ENCRYPT ERROR: packet ID roll over");
++ goto err;
+ }
+ if (ctx->hmac)
+ {
+Index: openvpn-2.4.0/src/openvpn/packet_id.c
+===================================================================
+--- openvpn-2.4.0.orig/src/openvpn/packet_id.c
++++ openvpn-2.4.0/src/openvpn/packet_id.c
+@@ -325,27 +325,37 @@ packet_id_read(struct packet_id_net *pin
+ return true;
+ }
+
+-static void
++static bool
+ packet_id_send_update(struct packet_id_send *p, bool long_form)
+ {
+ if (!p->time)
+ {
+ p->time = now;
+ }
+- p->id++;
+- if (!p->id)
++ if (p->id == PACKET_ID_MAX)
+ {
+- ASSERT(long_form);
++ /* Packet ID only allowed to roll over if using long form and time has
++ * moved forward since last roll over.
++ */
++ if (!long_form || now <= p->time)
++ {
++ return false;
++ }
+ p->time = now;
+- p->id = 1;
++ p->id = 0;
+ }
++ p->id++;
++ return true;
+ }
+
+ bool
+ packet_id_write(struct packet_id_send *p, struct buffer *buf, bool long_form,
+ bool prepend)
+ {
+- packet_id_send_update(p, long_form);
++ if (!packet_id_send_update(p, long_form))
++ {
++ return false;
++ }
+
+ const packet_id_type net_id = htonpid(p->id);
+ const net_time_t net_time = htontime(p->time);
+Index: openvpn-2.4.0/src/openvpn/packet_id.h
+===================================================================
+--- openvpn-2.4.0.orig/src/openvpn/packet_id.h
++++ openvpn-2.4.0/src/openvpn/packet_id.h
+@@ -50,6 +50,7 @@
+ * to for network transmission.
+ */
+ typedef uint32_t packet_id_type;
++#define PACKET_ID_MAX UINT32_MAX
+ typedef uint32_t net_time_t;
+
+ /*
+Index: openvpn-2.4.0/src/openvpn/tls_crypt.c
+===================================================================
+--- openvpn-2.4.0.orig/src/openvpn/tls_crypt.c
++++ openvpn-2.4.0/src/openvpn/tls_crypt.c
+@@ -95,7 +95,11 @@ tls_crypt_wrap(const struct buffer *src,
+ format_hex(BPTR(src), BLEN(src), 80, &gc));
+
+ /* Get packet ID */
+- ASSERT(packet_id_write(&opt->packet_id.send, dst, true, false));
++ if (!packet_id_write(&opt->packet_id.send, dst, true, false))
++ {
++ msg(D_CRYPT_ERRORS, "TLS-CRYPT ERROR: packet ID roll over.");
++ goto err;
++ }
+
+ dmsg(D_PACKET_CONTENT, "TLS-CRYPT WRAP AD: %s",
+ format_hex(BPTR(dst), BLEN(dst), 0, &gc));
+Index: openvpn-2.4.0/tests/unit_tests/openvpn/test_packet_id.c
+===================================================================
+--- openvpn-2.4.0.orig/tests/unit_tests/openvpn/test_packet_id.c
++++ openvpn-2.4.0/tests/unit_tests/openvpn/test_packet_id.c
+@@ -129,8 +129,7 @@ test_packet_id_write_short_wrap(void **s
+ struct test_packet_id_write_data *data = *state;
+
+ data->pis.id = ~0;
+- expect_assert_failure(
+- packet_id_write(&data->pis, &data->test_buf, false, false));
++ assert_false(packet_id_write(&data->pis, &data->test_buf, false, false));
+ }
+
+ static void
+@@ -139,8 +138,16 @@ test_packet_id_write_long_wrap(void **st
+ struct test_packet_id_write_data *data = *state;
+
+ data->pis.id = ~0;
++ data->pis.time = 5006;
++
++ /* Write fails if time did not change */
++ now = 5006;
++ assert_false(packet_id_write(&data->pis, &data->test_buf, true, false));
++
++ /* Write succeeds if time moved forward */
+ now = 5010;
+ assert_true(packet_id_write(&data->pis, &data->test_buf, true, false));
++
+ assert(data->pis.id == 1);
+ assert(data->pis.time == now);
+ assert_true(data->test_buf_data.buf_id == htonl(1));
diff --git a/debian/patches/series b/debian/patches/series
index 50b527d..457e897 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -3,3 +3,7 @@ debian_nogroup_for_sample_files.patch
openvpn-pkcs11warn.patch
kfreebsd_support.patch
match-manpage-and-command-help.patch
+CVE-2017-7478.patch
+CVE-2017-7479-prereq.patch
+CVE-2017-7479.patch
+wipe_tokens_on_de-auth.patch
diff --git a/debian/patches/wipe_tokens_on_de-auth.patch b/debian/patches/wipe_tokens_on_de-auth.patch
new file mode 100644
index 0000000..8db560f
--- /dev/null
+++ b/debian/patches/wipe_tokens_on_de-auth.patch
@@ -0,0 +1,118 @@
+From daab0a9fa8ff4f40e8a34707db0ac156d49fbfcb Mon Sep 17 00:00:00 2001
+From: David Sommerseth <davids@openvpn.net>
+Date: Tue, 28 Mar 2017 22:53:46 +0200
+Subject: [PATCH] auth-token: Ensure tokens are always wiped on de-auth
+
+If tls_deauthenticate() was called, it could in some scenarios leave the
+authentication token for a session in memory. This change just ensures
+auth-tokens are always wiped as soon as a TLS session is considered
+broken.
+
+Signed-off-by: David Sommerseth <davids@openvpn.net>
+
+Acked-by: Steffan Karger <steffan@karger.me>
+Message-Id: <20170328205346.18844-1-davids@openvpn.net>
+URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg14344.html
+Signed-off-by: David Sommerseth <davids@openvpn.net>
+---
+ src/openvpn/ssl_verify.c | 47 +++++++++++++++++++++++++++--------------------
+ 1 file changed, 27 insertions(+), 20 deletions(-)
+
+Index: openvpn-2.4.0/src/openvpn/ssl_verify.c
+===================================================================
+--- openvpn-2.4.0.orig/src/openvpn/ssl_verify.c
++++ openvpn-2.4.0/src/openvpn/ssl_verify.c
+@@ -80,6 +80,28 @@ setenv_untrusted(struct tls_session *ses
+ setenv_link_socket_actual(session->opt->es, "untrusted", &session->untrusted_addr, SA_IP_PORT);
+ }
+
++
++/**
++ * Wipes the authentication token out of the memory, frees and cleans up related buffers and flags
++ *
++ * @param multi Pointer to a multi object holding the auth_token variables
++ */
++static void
++wipe_auth_token(struct tls_multi *multi)
++{
++ if(multi)
++ {
++ if (multi->auth_token)
++ {
++ secure_memzero(multi->auth_token, AUTH_TOKEN_SIZE);
++ free(multi->auth_token);
++ }
++ multi->auth_token = NULL;
++ multi->auth_token_sent = false;
++ }
++}
++
++
+ /*
+ * Remove authenticated state from all sessions in the given tunnel
+ */
+@@ -88,10 +110,14 @@ tls_deauthenticate(struct tls_multi *mul
+ {
+ if (multi)
+ {
+- int i, j;
+- for (i = 0; i < TM_SIZE; ++i)
+- for (j = 0; j < KS_SIZE; ++j)
++ wipe_auth_token(multi);
++ for (int i = 0; i < TM_SIZE; ++i)
++ {
++ for (int j = 0; j < KS_SIZE; ++j)
++ {
+ multi->session[i].key[j].authenticated = false;
++ }
++ }
+ }
+ }
+
+@@ -1213,21 +1239,6 @@ verify_user_pass_management(struct tls_s
+ }
+ #endif /* ifdef MANAGEMENT_DEF_AUTH */
+
+-/**
+- * Wipes the authentication token out of the memory, frees and cleans up related buffers and flags
+- *
+- * @param multi Pointer to a multi object holding the auth_token variables
+- */
+-static void
+-wipe_auth_token(struct tls_multi *multi)
+-{
+- secure_memzero(multi->auth_token, AUTH_TOKEN_SIZE);
+- free(multi->auth_token);
+- multi->auth_token = NULL;
+- multi->auth_token_sent = false;
+-}
+-
+-
+ /*
+ * Main username/password verification entry point
+ */
+@@ -1279,7 +1290,7 @@ verify_user_pass(struct user_pass *up, s
+ /* Ensure that the username has not changed */
+ if (!tls_lock_username(multi, up->username))
+ {
+- wipe_auth_token(multi);
++ /* auth-token cleared in tls_lock_username() on failure */
+ ks->authenticated = false;
+ goto done;
+ }
+@@ -1300,7 +1311,6 @@ verify_user_pass(struct user_pass *up, s
+ if (memcmp_constant_time(multi->auth_token, up->password,
+ strlen(multi->auth_token)) != 0)
+ {
+- wipe_auth_token(multi);
+ ks->authenticated = false;
+ tls_deauthenticate(multi);
+
+@@ -1472,6 +1482,7 @@ verify_final_auth_checks(struct tls_mult
+ if (!cn || !strcmp(cn, CCD_DEFAULT) || !test_file(path))
+ {
+ ks->authenticated = false;
++ wipe_auth_token(multi);
+ msg(D_TLS_ERRORS, "TLS Auth Error: --client-config-dir authentication failed for common name '%s' file='%s'",
+ session->common_name,
+ path ? path : "UNDEF");