From patchwork Tue Dec 7 01:11:33 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Antonio Quartulli X-Patchwork-Id: 2119 Return-Path: Delivered-To: patchwork@openvpn.net Delivered-To: patchwork@openvpn.net Received: from director11.mail.ord1d.rsapps.net ([172.27.255.52]) by backend41.mail.ord1d.rsapps.net with LMTP id qEFXI+BPr2FELgAAqwncew (envelope-from ) for ; Tue, 07 Dec 2021 07:13:20 -0500 Received: from proxy16.mail.iad3a.rsapps.net ([172.27.255.52]) by director11.mail.ord1d.rsapps.net with LMTP id IJ/5MuBPr2F2awAAvGGmqA (envelope-from ) for ; Tue, 07 Dec 2021 07:13:20 -0500 Received: from smtp21.gate.iad3a ([172.27.255.52]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) by proxy16.mail.iad3a.rsapps.net with LMTPS id MN4fLOBPr2FWGwAADc5QwQ (envelope-from ) for ; Tue, 07 Dec 2021 07:13:20 -0500 X-Spam-Threshold: 95 X-Spam-Score: 0 X-Spam-Flag: NO X-Virus-Scanned: OK X-Orig-To: openvpnslackdevel@openvpn.net X-Originating-Ip: [216.105.38.7] Authentication-Results: smtp21.gate.iad3a.rsapps.net; iprev=pass policy.iprev="216.105.38.7"; spf=pass smtp.mailfrom="openvpn-devel-bounces@lists.sourceforge.net" smtp.helo="lists.sourceforge.net"; dkim=fail (signature verification failed) header.d=sourceforge.net; dkim=fail (signature verification failed) header.d=sf.net; dmarc=none (p=nil; dis=none) header.from=unstable.cc X-Suspicious-Flag: YES X-Classification-ID: 10736818-5757-11ec-96e8-525400e75841-1-1 Received: from [216.105.38.7] ([216.105.38.7:33068] helo=lists.sourceforge.net) by smtp21.gate.iad3a.rsapps.net (envelope-from ) (ecelerity 4.2.38.62370 r(:)) with ESMTPS (cipher=DHE-RSA-AES256-GCM-SHA384) id 09/32-23455-FDF4FA16; Tue, 07 Dec 2021 07:13:20 -0500 Received: from [127.0.0.1] (helo=sfs-ml-1.v29.lw.sourceforge.com) by sfs-ml-1.v29.lw.sourceforge.com with esmtp (Exim 4.94.2) (envelope-from ) id 1muZKV-0004qA-Po; Tue, 07 Dec 2021 12:12:20 +0000 Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-1.v29.lw.sourceforge.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1muZKS-0004p7-EJ for openvpn-devel@lists.sourceforge.net; Tue, 07 Dec 2021 12:12:17 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=Content-Transfer-Encoding:MIME-Version:References: In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=FL68yQ8Kt/wGTfv6yy/qm7XWBCwmUjLy+LuVyUYMtnw=; b=jlr5ur6u46HSjOCBDYw6u9Paek uSDfhaDE1+8XRWVGsVB+rDc7QaSQwBgHPjImjIXE8TUGCC4Eyfz0PU8YhX5K/Dz3y8a19ypLfP8/9 LLTC3ycTSXBP+QqrjcU534qGWXOPAMMWKaiDKQqtBrM5VnbVAdeAbwkYJID+YxFIdvv8=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-Id: Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=FL68yQ8Kt/wGTfv6yy/qm7XWBCwmUjLy+LuVyUYMtnw=; b=eEIDm4Y4Lu6n1buErKjLlTD9Dw 1Dnk2/GwzmU0I3Mei1E2GaLkmIae6d7P04pe5lPC60/fJbqVCjNXYFor9QdgT1qfVVNr/FoUztMEm 2d4n636jjwArwwnWBF8guqM23cd8sSq7ezz51FN4/39HbuRCDeCQ9TQEuccZVp7icfzc=; Received: from s2.neomailbox.net ([5.148.176.60]) by sfi-mx-2.v28.lw.sourceforge.com with esmtps (TLSv1.2:DHE-RSA-AES256-GCM-SHA384:256) (Exim 4.92.3) id 1muZKI-0008P3-LK for openvpn-devel@lists.sourceforge.net; Tue, 07 Dec 2021 12:12:13 +0000 From: Antonio Quartulli To: openvpn-devel@lists.sourceforge.net Date: Tue, 7 Dec 2021 13:11:33 +0100 Message-Id: <20211207121137.3221-5-a@unstable.cc> In-Reply-To: <20211207121137.3221-1-a@unstable.cc> References: <20211207121137.3221-1-a@unstable.cc> MIME-Version: 1.0 X-Spam-Report: Spam detection software, running on the system "util-spamd-1.v13.lw.sourceforge.com", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: From: Arne Schwabe Implement the data-channel offloading using the ovpn-dco kernel module. See README.dco.md for more details. Signed-off-by: Arne Schwabe Signed-off-by: Antonio Quartulli --- Changes.rst | 7 + README.dco.md | 124 +++ configure.ac | 56 ++ doc/man-sections/advanced-options.rst [...] Content analysis details: (0.0 points, 6.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record X-Headers-End: 1muZKI-0008P3-LK Subject: [Openvpn-devel] [RFC 4/8] ovpn-dco: introduce linux data-channel offload support X-BeenThere: openvpn-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Antonio Quartulli Errors-To: openvpn-devel-bounces@lists.sourceforge.net X-getmail-retrieved-from-mailbox: Inbox From: Arne Schwabe Implement the data-channel offloading using the ovpn-dco kernel module. See README.dco.md for more details. Signed-off-by: Arne Schwabe Signed-off-by: Antonio Quartulli --- Changes.rst | 7 + README.dco.md | 124 +++ configure.ac | 56 ++ doc/man-sections/advanced-options.rst | 13 + src/openvpn/Makefile.am | 8 +- src/openvpn/crypto.c | 10 + src/openvpn/crypto.h | 6 + src/openvpn/dco.c | 272 +++++++ src/openvpn/dco.h | 118 +++ src/openvpn/errlevel.h | 2 + src/openvpn/event.h | 3 + src/openvpn/forward.c | 66 +- src/openvpn/init.c | 153 +++- src/openvpn/init.h | 2 +- src/openvpn/mtcp.c | 61 +- src/openvpn/mudp.c | 13 + src/openvpn/multi.c | 278 ++++++- src/openvpn/multi.h | 6 +- src/openvpn/networking.h | 1 + src/openvpn/networking_linuxdco.c | 848 +++++++++++++++++++++ src/openvpn/networking_linuxdco.h | 85 +++ src/openvpn/openvpn.vcxproj | 4 +- src/openvpn/openvpn.vcxproj.filters | 6 + src/openvpn/options.c | 143 +++- src/openvpn/options.h | 26 + src/openvpn/socket.h | 1 + src/openvpn/ssl.c | 6 +- src/openvpn/ssl_common.h | 13 + src/openvpn/ssl_ncp.c | 2 +- src/openvpn/tun.c | 13 +- src/openvpn/tun.h | 4 + tests/unit_tests/openvpn/test_networking.c | 9 +- 32 files changed, 2305 insertions(+), 54 deletions(-) create mode 100644 README.dco.md create mode 100644 src/openvpn/dco.c create mode 100644 src/openvpn/dco.h create mode 100644 src/openvpn/networking_linuxdco.c create mode 100644 src/openvpn/networking_linuxdco.h diff --git a/Changes.rst b/Changes.rst index b7d7f205..b613d656 100644 --- a/Changes.rst +++ b/Changes.rst @@ -62,6 +62,13 @@ Optional ciphers in ``--data-ciphers`` Ciphers in ``--data-ciphers`` can now be prefixed with a ``?`` to mark those as optional and only use them if the SSL library supports them. +Data channel offloading with ovpn-dco + 2.6.0+ implements support for data-channel offloading where the data packets + are directly processed and forwarded in kernel space thanks to the ovpn-dco + kernel module. The userspace openvpn program acts purely as a control plane + application. + + Deprecated features ------------------- ``inetd`` has been removed diff --git a/README.dco.md b/README.dco.md new file mode 100644 index 00000000..e2500d36 --- /dev/null +++ b/README.dco.md @@ -0,0 +1,124 @@ +OpenVPN data channel offload +============================ +2.6.0+ implements support for data-channel offloading where the data packets +are directly processed and forwarded in kernel space thanks to the ovpn-dco +kernel module. The userspace openvpn program acts purely as a control plane +application. + +Overview of current release +--------------------------- +- See the "Limitations by design" and "Current limitations" sections for + features that are not and/or will not be supported by OpenVPN + ovpn-dco +- The dco branch is based on my working branch and contains a number of + other patch sets that are not yet merged into the OpenVPN master branch + (e.g. --peer-fingerprint). + + +Getting started (Linux) +----------------------- + +- Use a recent Linux kernel. Ubuntu 20.04 (Linux 5.4.0) and Ubuntu 20.10 + (Linux 5.8.0) are known to work with ovpn-dco. + +Get the ovpn-dco module from one these urls and build it: + +* https://gitlab.com/openvpn/ovpn-dco +* https://github.com/OpenVPN/ovpn-dco + +e.g. + + git clone https://github.com/OpenVPN/ovpn-dco + cd ovpn-dco + make + sudo make install + +If you want to report bugs please ensure to compile ovpn-dco with +`make DEBUG=1` and include any debug message being printed by the +kernel (you can view those messages with `dmesg`). + +Clone OpenVPN and build dco branch. For example: + + git clone -b dco https://github.com/schwabe/openvpn.git + cd openvpn + autoreconf -vi + ./configure --enable-dco + make + make install # Or run just src/openvpn/openvpn + +If you start openvpn it should automatically detect DCO support and use the +kernel module. Add the option `--disable-dco` to disable data channel offload +support. If the configuration contains an option that is incompatible with +data channel offloading OpenVPN will automatically disable DCO support and +warn the user. + +Should OpenVPN be configured to use a feature that is not supported by ovpn-dco +or should the ovpn-dco kernel module not be available on the system, you will +see a message like + + Note: Kernel support for ovpn-dco missing, disabling data channel offload. + +in your log. + + +DCO and P2P mode +---------------- +DCO is also available when running OpenVPN in P2P mode without --pull/--client option. +The P2P mode is useful for scenarios when the OpenVPN tunnel should not interfere with +overall routing and behave more like a "dumb" tunnel like GRE. + +However, DCO requires DATA_V2 to be enabled this requires P2P with NCP capability, which +is only available in OpenVPN 2.6 and later. + +OpenVPN prints a diagnostic message for the P2P NCP result when running in P2P mode: + + P2P mode NCP negotiation result: TLS_export=1, DATA_v2=1, peer-id 9484735, cipher=AES-256-GCM + +Double check that your have `DATA_v2=1` in your output and a supported AEAD cipher +(AES-GCM or Chacha20-Poly1305). + +Routing with ovpn-dco +--------------------- +The ovpn-dco kernel module implements a more transparent approach to +configuring routes to clients (aka 'iroutes') and consults the kernel +routing tables for forwarding decisions. + +- Each client has an IPv4 VPN IP and/or an IPv6 assigned to it +- Additional IP ranges can be routed to a client by adding a route with + a client VPN IP as the gateway/nexthop. +- No internal routing (iroutes) is available. If you need truly internal + routes, this can be achieved either with filtering using `iptables` or + using `ip rule`. + + +Limitations by design +---------------------- +- Layer 3 (dev tun only) +- only AEAD ciphers are supported and currently only + Chacha20-Poly1305 and AES-GCM-128/192/256 +- no support for compression or compression framing + - see also `--compress migrate` option to move to a setup with compression +- various features not implemented since have better replacements + - --shaper, use tc instead + - packet manipulation, use nftables/iptables instead +- OpenVPN 2.4.0 is the minimum peer version. + - older version are missing support for the AEAD ciphers +- topology subnet is the only supported `--topology` for servers +- iroute directives install routes on the host operating system, see also + routing with ovpn-dco + +Current limitations +------------------- +- --persistent-tun not tested/supported +- fallback to non-dco in client mode missing +- IPv6 mapped IPv4 addresses need Linux 5.12 to properly work +- Some incompatible options may not properly fallback to non-dco +- TCP performance with ovpn-dco can still exhibit bad behaviour and drop to a + few megabits per seconds. +- Not all options that should trigger disabling DCO as they are incompatible + are currently identified. Some options that do not trigger disabling DCO + are ignored while other might yield unexpected results. +- ovpn-dco currently does not implement RPF checks and will accept any source + IP from any client. +- If a peer VPN IP is outside the default device subnet, the route needs to be + added manually. +- No per client statistics. Only total statistics available on the interface. diff --git a/configure.ac b/configure.ac index e0f9c332..7d05d905 100644 --- a/configure.ac +++ b/configure.ac @@ -142,6 +142,13 @@ AC_ARG_ENABLE( [enable_small="no"] ) +AC_ARG_ENABLE( + [dco], + [AS_HELP_STRING([--enable-dco], [enable data channel offload support using ovpn-dco kernel module @<:@default=no@:>@])], + , + [enable_dco="no"] +) + AC_ARG_ENABLE( [iproute2], [AS_HELP_STRING([--enable-iproute2], [enable support for iproute2 @<:@default=no@:>@])], @@ -766,6 +773,53 @@ PKG_CHECK_MODULES( [] ) + + +if test "$enable_dco" = "yes"; then +dnl +dnl Configure path for the ovpn-dco kernel module source directory. +dnl +dnl This is similar to the core librariy, there is an embedded +dnl version in this tree which will be used by default. The +dnl git checkout inside the ovpn-dco/ directory is managed via git +dnl submodule. +dnl +AC_ARG_VAR([DCO_SOURCEDIR], [Alternative ovpn-dco kernel module source directory]) +if test -z "${DCO_SOURCEDIR}"; then + DCO_SOURCEDIR="${srcdir}/../ovpn-dco" +fi +AC_MSG_NOTICE([Using ovpn-dco source directory: ${DCO_SOURCEDIR}]) +AC_SUBST([DCO_SOURCEDIR]) + +dnl +dnl Include generic netlink library used to talk to ovpn-dco +dnl + saved_CFLAGS="${CFLAGS}" + PKG_CHECK_MODULES( + [LIBNL_GENL], + [libnl-genl-3.0 >= 3.2.29], + [have_libnl="yes"], + [AC_MSG_ERROR([libnl-genl-3.0 package not found or too old. Is the development package and pkg-config installed? Must be version 3.4.0 or newer])] + ) + + DCO_CFLAGS="-I${DCO_SOURCEDIR}/include/uapi ${LIBNL_GENL_CFLAGS}" + + CFLAGS="${CFLAGS} ${DCO_CFLAGS}" + AC_CHECK_HEADERS( + [linux/ovpn_dco.h], + , + [AC_MSG_ERROR([linux/ovpn_dco.h is missing (use DCO_SOURCE to set path to it, CFLAGS=${CFLAGS})])] + ) + CFLAGS=${saved_CFLAGS} + OPTIONAL_DCO_CFLAGS="${DCO_CFLAGS}" + OPTIONAL_DCO_LIBS="${LIBNL_GENL_LIBS}" + + AC_DEFINE(ENABLE_LINUXDCO, 1, [Enable linux data channel offload]) + AC_DEFINE(ENABLE_DCO, 1, [Enable shared data channel offload]) +fi +AM_CONDITIONAL([ENABLE_OVPNDCO], [test "${enable_dco}" = "yes"]) + + if test "${with_crypto_library}" = "openssl"; then AC_ARG_VAR([OPENSSL_CFLAGS], [C compiler flags for OpenSSL]) AC_ARG_VAR([OPENSSL_LIBS], [linker flags for OpenSSL]) @@ -1331,6 +1385,8 @@ AC_SUBST([OPTIONAL_PKCS11_HELPER_CFLAGS]) AC_SUBST([OPTIONAL_PKCS11_HELPER_LIBS]) AC_SUBST([OPTIONAL_INOTIFY_CFLAGS]) AC_SUBST([OPTIONAL_INOTIFY_LIBS]) +AC_SUBST([OPTIONAL_DCO_CFLAGS]) +AC_SUBST([OPTIONAL_DCO_LIBS]) AC_SUBST([PLUGIN_AUTH_PAM_CFLAGS]) AC_SUBST([PLUGIN_AUTH_PAM_LIBS]) diff --git a/doc/man-sections/advanced-options.rst b/doc/man-sections/advanced-options.rst index 5157c561..cdec9502 100644 --- a/doc/man-sections/advanced-options.rst +++ b/doc/man-sections/advanced-options.rst @@ -91,3 +91,16 @@ used when debugging or testing out special usage scenarios. *(Linux only)* Set the TX queue length on the TUN/TAP interface. Currently defaults to operating system default. +--disable-dco + Disables the opportunistic use the data channel offloading if available. + Without this option, OpenVPN will opportunistically use DCO mode if + the config options and the running kernel supports using DCO. + + Data channel offload currently requires data-ciphers to only contain + AEAD ciphers (AES-GCM and Chacha20-Poly1305) and Linux with the + ovpn-dco module. + + Note that some options have no effect or not available when + DCO mode is enabled. + + A platforms that do not support DCO ``disable-dco`` has no effect. diff --git a/src/openvpn/Makefile.am b/src/openvpn/Makefile.am index 5883c291..0cc06155 100644 --- a/src/openvpn/Makefile.am +++ b/src/openvpn/Makefile.am @@ -30,6 +30,7 @@ AM_CFLAGS = \ $(OPTIONAL_LZ4_CFLAGS) \ $(OPTIONAL_PKCS11_HELPER_CFLAGS) \ $(OPTIONAL_INOTIFY_CFLAGS) \ + ${OPTIONAL_DCO_CFLAGS} \ -DPLUGIN_LIBDIR=\"${plugindir}\" if WIN32 @@ -53,6 +54,7 @@ openvpn_SOURCES = \ crypto.c crypto.h crypto_backend.h \ crypto_openssl.c crypto_openssl.h \ crypto_mbedtls.c crypto_mbedtls.h \ + dco.c dco.h \ dhcp.c dhcp.h \ env_set.c env_set.h \ errlevel.h \ @@ -85,7 +87,8 @@ openvpn_SOURCES = \ multi.c multi.h \ networking_iproute2.c networking_iproute2.h \ networking_sitnl.c networking_sitnl.h \ - networking.h \ + networking_linuxdco.c networking_linuxdco.h \ + networking.h \ ntlm.c ntlm.h \ occ.c occ.h \ openssl_compat.h \ @@ -141,7 +144,8 @@ openvpn_LDADD = \ $(OPTIONAL_SELINUX_LIBS) \ $(OPTIONAL_SYSTEMD_LIBS) \ $(OPTIONAL_DL_LIBS) \ - $(OPTIONAL_INOTIFY_LIBS) + $(OPTIONAL_INOTIFY_LIBS) \ + $(OPTIONAL_DCO_LIBS) if WIN32 openvpn_SOURCES += openvpn_win32_resources.rc block_dns.c block_dns.h ring_buffer.h openvpn_LDADD += -lgdi32 -lws2_32 -lwininet -lcrypt32 -liphlpapi -lwinmm -lfwpuclnt -lrpcrt4 -lncrypt -lsetupapi diff --git a/src/openvpn/crypto.c b/src/openvpn/crypto.c index a63a2619..57869c66 100644 --- a/src/openvpn/crypto.c +++ b/src/openvpn/crypto.c @@ -826,6 +826,16 @@ init_key_ctx(struct key_ctx *ctx, const struct key *key, cipher_kt_iv_size(kt->cipher)); warn_insecure_key_type(ciphername, kt->cipher); } + +#if defined(ENABLE_DCO) + /* Keep key material for DCO */ + static_assert(sizeof(key->cipher) == sizeof(ctx->aead_key), "DCO key size mismatch"); + if (kt->keep_key_data) + { + memcpy(ctx->aead_key, key->cipher, sizeof(ctx->aead_key)); + } +#endif + if (kt->digest) { ctx->hmac = hmac_ctx_new(); diff --git a/src/openvpn/crypto.h b/src/openvpn/crypto.h index 1e2ca3cb..bec6883c 100644 --- a/src/openvpn/crypto.h +++ b/src/openvpn/crypto.h @@ -140,6 +140,9 @@ struct key_type { const cipher_kt_t *cipher; /**< Cipher static parameters */ const md_kt_t *digest; /**< Message digest static parameters */ +#if defined(ENABLE_DCO) + bool keep_key_data; +#endif }; /** @@ -166,6 +169,9 @@ struct key_ctx uint8_t implicit_iv[OPENVPN_MAX_IV_LENGTH]; /**< The implicit part of the IV */ size_t implicit_iv_len; /**< The length of implicit_iv */ +#if defined(ENABLE_DCO) + uint8_t aead_key[MAX_CIPHER_KEY_LENGTH]; /**< Keeps the key data for use with DCO */ +#endif }; #define KEY_DIRECTION_BIDIRECTIONAL 0 /* same keys for both directions */ diff --git a/src/openvpn/dco.c b/src/openvpn/dco.c new file mode 100644 index 00000000..b04122b6 --- /dev/null +++ b/src/openvpn/dco.c @@ -0,0 +1,272 @@ +/* + * OpenVPN -- An application to securely tunnel IP networks + * over a single TCP/UDP port, with support for SSL/TLS-based + * session authentication and key exchange, + * packet encryption, packet authentication, and + * packet compression. + * + * Copyright (C) 2021 Arne Schwabe + * Copyright (C) 2021 OpenVPN Inc + * + * 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 "errlevel.h" +#include "networking.h" + +#include "multi.h" +#include "dco.h" +#include "networking_linuxdco.h" + +#if defined(ENABLE_DCO) +#include "ssl_verify.h" + +bool +dco_do_key_dance(struct tuntap *tt, struct tls_multi *multi, const char *ciphername) +{ + struct key_state *primary = tls_select_encryption_key(multi); + struct key_state *secondary = NULL; + + for (int i = 0; i < KEY_SCAN_SIZE; ++i) + { + struct key_state *ks = get_key_scan(multi, i); + struct key_ctx_bi *key = &ks->crypto_options.key_ctx_bi; + + if (ks == primary) + { + continue; + } + + if (ks->state >= S_GENERATED_KEYS) + { + ASSERT(ks->authenticated == KS_AUTH_TRUE); + ASSERT(key->initialized); + + secondary = ks; + } + } + + if (!primary) + { + if (multi->dco_keys_installed >= 1) + { + msg(D_DCO, "DCO: No encryption key found. Purging data channel keys"); + dco_del_key(tt, multi->peer_id, OVPN_KEY_SLOT_PRIMARY); + if (multi->dco_keys_installed == 2) + { + dco_del_key(tt, multi->peer_id, OVPN_KEY_SLOT_SECONDARY); + } + multi->dco_keys_installed = 2; + } + return false; + } + + /* All keys installed as they should */ + if (primary->dco_status == DCO_INSTALLED_PRIMARY + && (!secondary || secondary->dco_status == DCO_INSTALLED_SECONDARY)) + { + /* Check if we have a previously installed secondary key */ + if (!secondary && multi->dco_keys_installed == 2) + { + multi->dco_keys_installed = 1; + dco_del_key(tt, multi->peer_id, OVPN_KEY_SLOT_SECONDARY); + } + return true; + } + + int pid = primary->key_id; + int sid = secondary ? secondary->key_id : -1; + + msg(D_DCO_DEBUG, "Installing DCO data channel keys for peer %d, " + "primary key-id: %d, secondary key-id: %d.", + multi->peer_id, pid, sid); + + /* General strategy, get primary key installed correctly first. If that is + * okay then check if we need to exchange secondary */ + if (primary->dco_status != DCO_INSTALLED_PRIMARY) + { + /* ovpn-win-dco does not like to have the install as secondary and then + * swap to primary for the first key .... */ + if (multi->dco_keys_installed == 0) + { + dco_new_key(tt, multi->peer_id, OVPN_KEY_SLOT_PRIMARY, primary, ciphername); + multi->dco_keys_installed = 1; + } + else + { + if (primary->dco_status != DCO_INSTALLED_SECONDARY) + { + dco_new_key(tt, multi->peer_id, OVPN_KEY_SLOT_SECONDARY, primary, ciphername); + } + dco_swap_keys(tt, multi->peer_id); + } + primary->dco_status = DCO_INSTALLED_PRIMARY; + + /* if the secondary was installed as primary before the swap demoted + * it to secondary */ + if (secondary && secondary->dco_status == DCO_INSTALLED_PRIMARY) + { + secondary->dco_status = DCO_INSTALLED_SECONDARY; + multi->dco_keys_installed = 2; + } + } + + /* The primary key is now the correct key but the secondary key might + * already a new key that will be later promoted to primary key and we + * need to install the key */ + if (secondary && secondary->dco_status != DCO_INSTALLED_SECONDARY) + { + dco_new_key(tt, multi->peer_id, OVPN_KEY_SLOT_SECONDARY, secondary, ciphername); + secondary->dco_status = DCO_INSTALLED_SECONDARY; + multi->dco_keys_installed = 2; + } + /* delete an expired key */ + if (!secondary && multi->dco_keys_installed == 2) + { + dco_del_key(tt, multi->peer_id, OVPN_KEY_SLOT_SECONDARY); + multi->dco_keys_installed = 1; + } + + /* All keys that we have not installed are set to NOT installed */ + for (int i = 0; i < KEY_SCAN_SIZE; ++i) + { + struct key_state *ks = get_key_scan(multi, i); + if (ks != primary && ks != secondary) + { + ks->dco_status = DCO_NOT_INSTALLED; + } + } + return true; +} + +int +get_dco_cipher(const char *cipher) +{ + if (streq(cipher, "AES-256-GCM") || streq(cipher, "AES-128-GCM") || + streq(cipher, "AES-192-GCM")) + return OVPN_CIPHER_ALG_AES_GCM; + else if (streq(cipher, "CHACHA20-POLY1305")) + { + return OVPN_CIPHER_ALG_CHACHA20_POLY1305; + } + else if (strcmp(cipher, "none") == 0) + { + return OVPN_CIPHER_ALG_NONE; + } + else + { + return -ENOTSUP; + } +} +#endif + +/* These methods are currently Linux specified but likely to be used any platform that implements Server side DCO */ +#if defined(ENABLE_LINUXDCO) + +void +dco_install_iroute(struct multi_context *m, struct multi_instance *mi, + struct mroute_addr *addr, bool primary) +{ + if (!dco_enabled(&m->top.options)) + { + return; + } + + if (primary) + { + /* We do not want to install IP -> IP dev ovpn-dco0 */ + return; + } + + int addrtype = (addr->type & MR_ADDR_MASK); + + /* If we do not have local IP addr to install, skip the route */ + if ((addrtype == MR_ADDR_IPV6 && !mi->context.c2.push_ifconfig_ipv6_defined) + || (addrtype == MR_ADDR_IPV4 && !mi->context.c2.push_ifconfig_defined)) + { + return; + } + + struct context *c = &mi->context; + const char *dev = c->c1.tuntap->actual_name; + + if (addrtype == MR_ADDR_IPV6) + { + net_route_v6_add(&m->top.net_ctx, &addr->v6.addr, addr->netbits, + &mi->context.c2.push_ifconfig_ipv6_local, dev, 0, + DCO_IROUTE_METRIC); + } + else if (addrtype == MR_ADDR_IPV4) + { + in_addr_t dest = htonl(addr->v4.addr); + net_route_v4_add(&m->top.net_ctx, &dest, addr->netbits, + &mi->context.c2.push_ifconfig_local, dev, 0, + DCO_IROUTE_METRIC); + } +} + +void +dco_delete_iroutes(struct multi_context *m, struct multi_instance *mi) +{ + if (!dco_enabled(&m->top.options)) + { + return; + } + ASSERT(TUNNEL_TYPE(mi->context.c1.tuntap) == DEV_TYPE_TUN); + + struct context *c = &mi->context; + const char *dev = c->c1.tuntap->actual_name; + + if (mi->context.c2.push_ifconfig_defined) + { + for (const struct iroute *ir = c->options.iroutes; ir != NULL; ir = ir->next) + { + net_route_v4_del(&m->top.net_ctx, &ir->network, ir->netbits, + &mi->context.c2.push_ifconfig_local, dev, + 0, DCO_IROUTE_METRIC); + } + } + + if (mi->context.c2.push_ifconfig_ipv6_defined) + { + for (const struct iroute_ipv6 *ir6 = c->options.iroutes_ipv6; ir6 != NULL; ir6 = ir6->next) + { + net_route_v6_del(&m->top.net_ctx, &ir6->network, ir6->netbits, + &mi->context.c2.push_ifconfig_ipv6_local, dev, + 0, DCO_IROUTE_METRIC); + } + } +} +#else +void +dco_install_iroute(struct multi_context *m, struct multi_instance *mi, + struct mroute_addr *addr, bool primary) +{ +} + +void +dco_delete_iroutes(struct multi_context *m, struct multi_instance *mi) +{ +} +#endif \ No newline at end of file diff --git a/src/openvpn/dco.h b/src/openvpn/dco.h new file mode 100644 index 00000000..1cfdc8fb --- /dev/null +++ b/src/openvpn/dco.h @@ -0,0 +1,118 @@ +/* + * OpenVPN -- An application to securely tunnel IP networks + * over a single TCP/UDP port, with support for SSL/TLS-based + * session authentication and key exchange, + * packet encryption, packet authentication, and + * packet compression. + * + * Copyright (C) 2021 Arne Schwabe + * Copyright (C) 2021 OpenVPN Inc + * + * 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 + */ +#ifndef DCO_H +#define DCO_H + +/* forward declarations, including multi.h leads to nasty include + * order problems */ +struct multi_context; +struct tls_multi; +struct multi_instance; +struct mroute_addr; +struct tuntap; + +#if !defined(ENABLE_DCO) +/* Define dummy type for dco context if DCO is not enabled */ +typedef void *dco_context_t; + +static inline void open_tun_dco(struct tuntap *tt, const char* dev) { ASSERT(false); } + +static inline void close_tun_dco(struct tuntap *tt) { ASSERT(false); } +#else +#include "networking_linuxdco.h" +#include "crypto.h" + +/* forward declarations */ +struct tuntap; +struct key_state; + +void open_tun_dco(struct tuntap *tt, const char* dev); + +void close_tun_dco(struct tuntap *tt); + +int dco_new_peer(struct tuntap *tt, unsigned int peerid, int sd, + struct sockaddr *localaddr, struct sockaddr *remoteaddr, + struct in_addr *remote_in4, struct in6_addr *remote_in6); + + +int ovpn_set_peer(struct tuntap *tt, unsigned int peerid, + unsigned int keepalive_interval, + unsigned int keepalive_timeout); + +int ovpn_do_read_dco(struct dco_context *dco); +int dco_del_peer(struct tuntap *tt, unsigned int peerid); + +int +dco_del_key(struct tuntap *tt, unsigned int peerid, ovpn_key_slot_t slot); + +int +dco_new_key(struct tuntap *tt, unsigned int peerid, ovpn_key_slot_t slot, + struct key_state *ks, const char* ciphername); + +int dco_swap_keys(struct tuntap *tt, unsigned int peerid); + +/** + * Does the assertions that the key material is indeed sane. + * @param key the key context to be checked + */ +static inline void dco_check_key_ctx(const struct key_ctx_bi *key) +{ + ASSERT(key->initialized); + /* Double check that we do not have empty keys */ + const uint8_t empty_key[32] = { 0 }; + ASSERT(memcmp(key->encrypt.aead_key, empty_key, 32)); + ASSERT(memcmp(key->decrypt.aead_key, empty_key, 32)); +} + +#endif + +void +dco_install_iroute(struct multi_context *m, struct multi_instance *mi, + struct mroute_addr *addr, bool primary); + +void +dco_delete_iroutes(struct multi_context *m, struct multi_instance *mi); + + +/** + * This function will check if the encryption and decryption keys are installed + * to the data channel offload and if not do the necessary steps to ensure that + * openvpn and data channel are synced again + * + * @param tt Tun tap device context + * @param multi TLS multi instance + * @param ciphername Ciphername to use when installing the keys. + * @return + */ +bool +dco_do_key_dance(struct tuntap *tt, struct tls_multi *multi, const char *ciphername); + +/** + * Translates an OpenVPN Cipher string to a supported cipher enum from DCO + * @param cipher OpenVPN cipher string + * @return constant that defines the cipher or -ENOTSUP if not supported + */ +int get_dco_cipher(const char *cipher); +#endif \ No newline at end of file diff --git a/src/openvpn/errlevel.h b/src/openvpn/errlevel.h index 602e48a8..a7054647 100644 --- a/src/openvpn/errlevel.h +++ b/src/openvpn/errlevel.h @@ -91,6 +91,7 @@ #define D_OSBUF LOGLEV(3, 43, 0) /* show socket/tun/tap buffer sizes */ #define D_PS_PROXY LOGLEV(3, 44, 0) /* messages related to --port-share option */ #define D_IFCONFIG LOGLEV(3, 0, 0) /* show ifconfig info (don't mute) */ +#define D_DCO LOGLEV(3, 0, 0) /* show DCO related messages */ #define D_SHOW_PARMS LOGLEV(4, 50, 0) /* show all parameters on program initiation */ #define D_SHOW_OCC LOGLEV(4, 51, 0) /* show options compatibility string */ @@ -113,6 +114,7 @@ #define D_TUN_RW LOGLEV(6, 69, M_DEBUG) /* show TUN/TAP reads/writes */ #define D_TAP_WIN_DEBUG LOGLEV(6, 69, M_DEBUG) /* show TAP-Windows driver debug info */ #define D_CLIENT_NAT LOGLEV(6, 69, M_DEBUG) /* show client NAT debug info */ +#define D_DCO_DEBUG LOGLEV(6, 69, M_DEBUG) /* show DCO related lowlevel debug messages */ #define D_SHOW_KEYS LOGLEV(7, 70, M_DEBUG) /* show data channel encryption keys */ #define D_SHOW_KEY_SOURCE LOGLEV(7, 70, M_DEBUG) /* show data channel key source entropy */ diff --git a/src/openvpn/event.h b/src/openvpn/event.h index d67d69f6..fc815a59 100644 --- a/src/openvpn/event.h +++ b/src/openvpn/event.h @@ -72,6 +72,9 @@ #define MANAGEMENT_WRITE (1 << (MANAGEMENT_SHIFT + WRITE_SHIFT)) #define FILE_SHIFT 8 #define FILE_CLOSED (1 << (FILE_SHIFT + READ_SHIFT)) +#define DCO_SHIFT 10 +#define DCO_READ (1 << (DCO_SHIFT + READ_SHIFT)) +#define DCO_WRITE (1 << (DCO_SHIFT + WRITE_SHIFT)) /* * Initialization flags passed to event_set_init diff --git a/src/openvpn/forward.c b/src/openvpn/forward.c index 41ef12e3..02aa6659 100644 --- a/src/openvpn/forward.c +++ b/src/openvpn/forward.c @@ -41,6 +41,7 @@ #include "dhcp.h" #include "common.h" #include "ssl_verify.h" +#include "dco.h" #include "memdbg.h" @@ -50,7 +51,6 @@ counter_type link_read_bytes_global; /* GLOBAL */ counter_type link_write_bytes_global; /* GLOBAL */ /* show event wait debugging info */ - #ifdef ENABLE_DEBUG static const char * @@ -139,6 +139,22 @@ context_reschedule_sec(struct context *c, int sec) c->c2.timeval.tv_usec = 0; } } +#if defined(ENABLE_DCO) +static void +check_dco_key_status(struct context *c) +{ + /* DCO context is not yet initialised or enabled */ + if ((!c->c2.did_open_tun && !c->c1.tuntap)|| !dco_enabled(&c->options)) + { + return; + } + + struct tls_multi *multi = c->c2.tls_multi; + + dco_do_key_dance(c->c1.tuntap, multi, c->options.ciphername); +} +#endif + /* * In TLS mode, let TLS level respond to any control-channel @@ -181,6 +197,13 @@ check_tls(struct context *c) } interval_schedule_wakeup(&c->c2.tmp_int, &wakeup); +#if defined(ENABLE_DCO) + /* Our current code has no good hooks in the TLS machinery to install + * the keys to DCO. So we check/install keys after the whole TLS + * machinery has been completed + */ + check_dco_key_status(c); +#endif if (wakeup) { @@ -1084,6 +1107,15 @@ process_incoming_link(struct context *c) perf_pop(); } +#if defined(ENABLE_LINUXDCO) +static void +process_incoming_dco(struct context *c) +{ + msg(M_INFO, __func__); + ovpn_do_read_dco(&c->c1.tuntap->dco); +} +#endif + /* * Output: c->c2.buf */ @@ -1605,9 +1637,17 @@ process_outgoing_link(struct context *c) socks_preprocess_outgoing_link(c, &to_addr, &size_delta); /* Send packet */ - size = link_socket_write(c->c2.link_socket, - &c->c2.to_link, - to_addr); +#if defined(ENABLE_LINUXDCO) + if (c->c2.link_socket->info.dco_installed) + { + size = ovpn_do_write_dco(&c->c1.tuntap->dco, c->c2.tls_multi->peer_id, &c->c2.to_link); + } + else +#endif + { + size = link_socket_write(c->c2.link_socket, &c->c2.to_link, + to_addr); + } /* Undo effect of prepend */ link_socket_write_post_size_adjust(&size, size_delta, &c->c2.to_link); @@ -1870,6 +1910,9 @@ io_wait_dowork(struct context *c, const unsigned int flags) #ifdef ENABLE_ASYNC_PUSH static int file_shift = FILE_SHIFT; #endif +#ifdef ENABLE_LINUXDCO + static int dco_shift = 10; /* Event from DCO module */ +#endif /* * Decide what kind of events we want to wait for. @@ -1977,6 +2020,12 @@ io_wait_dowork(struct context *c, const unsigned int flags) */ socket_set(c->c2.link_socket, c->c2.event_set, socket, (void *)&socket_shift, NULL); tun_set(c->c1.tuntap, c->c2.event_set, tuntap, (void *)&tun_shift, NULL); +#if defined(ENABLE_LINUXDCO) + if (socket & EVENT_READ && c->c2.did_open_tun) + { + dco_event_set(&c->c1.tuntap->dco, c->c2.event_set, (void *) &dco_shift); + } +#endif #ifdef ENABLE_MANAGEMENT if (management) @@ -2099,4 +2148,13 @@ process_io(struct context *c) process_incoming_tun(c); } } +#if defined(ENABLE_LINUXDCO) + else if (status & DCO_READ) + { + if(!IS_SIG(c)) + { + process_incoming_dco(c); + } + } +#endif } diff --git a/src/openvpn/init.c b/src/openvpn/init.c index 4fee7f49..4668fd04 100644 --- a/src/openvpn/init.c +++ b/src/openvpn/init.c @@ -53,6 +53,7 @@ #include "tls_crypt.h" #include "forward.h" #include "auth_token.h" +#include "dco.h" #include "memdbg.h" @@ -1367,15 +1368,25 @@ do_init_timers(struct context *c, bool deferred) } /* initialize pings */ - - if (c->options.ping_send_timeout) +#if defined(ENABLE_DCO) + if (dco_enabled(&c->options)) { - event_timeout_init(&c->c2.ping_send_interval, c->options.ping_send_timeout, 0); + /* The DCO kernel module will send the pings instead of user space */ + event_timeout_clear(&c->c2.ping_rec_interval); + event_timeout_clear(&c->c2.ping_send_interval); } - - if (c->options.ping_rec_timeout) + else +#endif { - event_timeout_init(&c->c2.ping_rec_interval, c->options.ping_rec_timeout, now); + if (c->options.ping_send_timeout) + { + event_timeout_init(&c->c2.ping_send_interval, c->options.ping_send_timeout, 0); + } + + if (c->options.ping_rec_timeout) + { + event_timeout_init(&c->c2.ping_rec_interval, c->options.ping_rec_timeout, now); + } } if (!deferred) @@ -2097,6 +2108,7 @@ tun_abort(void) * Handle delayed tun/tap interface bringup due to --up-delay or --pull */ + /** * Helper for do_up(). Take two option hashes and return true if they are not * equal, or either one is all-zeroes. @@ -2110,6 +2122,85 @@ options_hash_changed_or_zero(const struct sha256_digest *a, || !memcmp(a, &zero, sizeof(struct sha256_digest)); } +#ifdef ENABLE_DCO +static bool +p2p_dco_add_new_peer(struct context *c) +{ + struct tls_multi *multi = c->c2.tls_multi; + struct link_socket *ls = c->c2.link_socket; + + if (!dco_enabled(&c->options)) + { + return true; + } + + struct in6_addr remote_ip6 = { 0 }; + struct in_addr remote_ip4 = { 0 }; + + struct in6_addr *remote_addr6 = NULL; + struct in_addr *remote_addr4 = NULL; + + const char* gw = NULL; + /* In client mode if a P2P style topology is used we assume the + * remote-gateway is the IP of the peer */ + if (c->options.topology == TOP_NET30 || c->options.topology == TOP_P2P) + { + gw = c->options.ifconfig_remote_netmask; + } + if (c->options.route_default_gateway) + { + gw = c->options.route_default_gateway; + } + + /* These inet_pton conversion are fatal since options.c already implements + * checks to have only valid addresses when setting the options */ + if (c->options.ifconfig_ipv6_remote) + { + if (inet_pton(AF_INET6, c->options.ifconfig_ipv6_remote, &remote_ip6) != 1) + { + msg(M_FATAL, + "DCO peer init: problem converting IPv6 ifconfig remote address %s to binary", + c->options.ifconfig_ipv6_remote); + } + remote_addr6 = &remote_ip6; + } + + if (gw) + { + if (inet_pton(AF_INET, gw, &remote_ip4) != 1) + { + msg(M_FATAL, "DCO peer init: problem converting IPv4 ifconfig gateway address %s to binary", gw); + } + remote_addr4 = &remote_ip4; + } + else if (c->options.ifconfig_local) + { + msg(M_INFO, "DCO peer init: Need a peer VPN addresss to setup IPv4 (set --route-gateway)"); + } + + if (!c->c2.link_socket->info.dco_installed) + { + ASSERT(ls->info.connection_established); + + struct sockaddr *remoteaddr = &ls->info.lsa->actual.dest.addr.sa; + + dco_new_peer(c->c1.tuntap, multi->peer_id, c->c2.link_socket->sd, NULL, + remoteaddr, remote_addr4, remote_addr6); + + c->c2.tls_multi->dco_peer_added = true; + c->c2.link_socket->info.dco_installed = true; + } + + if (c->options.ping_send_timeout) + { + ovpn_set_peer(c->c1.tuntap, multi->peer_id, c->options.ping_send_timeout, + c->options.ping_rec_timeout); + } + + return true; +} +#endif + bool do_up(struct context *c, bool pulled_options, unsigned int option_types_found) { @@ -2161,6 +2252,11 @@ do_up(struct context *c, bool pulled_options, unsigned int option_types_found) if (c->c2.did_open_tun) { + /* If we are in DCO mode we need to set the new peer options now */ +#if defined(ENABLE_DCO) + p2p_dco_add_new_peer(c); +#endif + c->c1.pulled_options_digest_save = c->c2.pulled_options_digest; /* if --route-delay was specified, start timer */ @@ -2288,6 +2384,18 @@ do_deferred_p2p_ncp(struct context *c) return true; } + +static bool check_dco_pull_options(struct options *o) +{ + if (!o->use_peer_id) + { + msg(D_TLS_ERRORS, "OPTIONS IMPORT: Server did not request DATA_V2 packet " + "format required for data channel offloading"); + return false; + } + return true; +} + /* * Handle non-tun-related pulled options. */ @@ -2400,8 +2508,17 @@ do_deferred_options(struct context *c, const unsigned int found) msg(D_TLS_ERRORS, "OPTIONS ERROR: failed to import crypto options"); return false; } - } + /* Check if the pushed options are compatible with DCO if we have DCO + * enabled */ + if (dco_enabled(&c->options) && !check_dco_pull_options(&c->options)) + { + msg(D_TLS_ERRORS, "OPTIONS ERROR: pushed options are incompatible with " + "data channel offloading. Use --disable-dco to connect" + "to this server"); + return false; + } + } return true; } @@ -4332,6 +4449,24 @@ sig: close_context(c, -1, flags); return; } +#if defined(ENABLE_LINUXDCO) +static void remove_dco_peer(struct context *c) +{ + if (!dco_enabled(&c->options)) + { + return; + } + if (c->c1.tuntap && c->c2.tls_multi && c->c2.tls_multi->dco_peer_added) + { + c->c2.tls_multi->dco_peer_added = false; + dco_del_peer(c->c1.tuntap, c->c2.tls_multi->peer_id); + } +} +#else +static void remove_dco_peer(struct context *c) +{ +} +#endif /* * Close a tunnel instance. @@ -4358,6 +4493,10 @@ close_instance(struct context *c) /* free buffers */ do_close_free_buf(c); + /* close peer for DCO if enabled, needs peer-id so must be done before + * closing TLS contexts */ + remove_dco_peer(c); + /* close TLS */ do_close_tls(c); diff --git a/src/openvpn/init.h b/src/openvpn/init.h index 52581f8a..5c719117 100644 --- a/src/openvpn/init.h +++ b/src/openvpn/init.h @@ -30,7 +30,7 @@ * Baseline maximum number of events * to wait for. */ -#define BASE_N_EVENTS 4 +#define BASE_N_EVENTS 5 void context_clear(struct context *c); diff --git a/src/openvpn/mtcp.c b/src/openvpn/mtcp.c index bf9b5190..e335dcef 100644 --- a/src/openvpn/mtcp.c +++ b/src/openvpn/mtcp.c @@ -61,6 +61,7 @@ #define MTCP_SIG ((void *)3) /* Only on Windows */ #define MTCP_MANAGEMENT ((void *)4) #define MTCP_FILE_CLOSE_WRITE ((void *)5) +#define MTCP_DCO ((void *)6) #define MTCP_N ((void *)16) /* upper bound on MTCP_x */ @@ -123,6 +124,8 @@ multi_create_instance_tcp(struct multi_context *m) struct hash *hash = m->hash; mi = multi_create_instance(m, NULL); + multi_assign_peer_id(m, mi); + if (mi) { struct hash_element *he; @@ -236,6 +239,7 @@ multi_tcp_dereference_instance(struct multi_tcp *mtcp, struct multi_instance *mi if (ls && mi->socket_set_called) { event_del(mtcp->es, socket_event_handle(ls)); + mi->socket_set_called = false; } mtcp->n_esr = 0; } @@ -277,6 +281,9 @@ multi_tcp_wait(const struct context *c, } #endif tun_set(c->c1.tuntap, mtcp->es, EVENT_READ, MTCP_TUN, persistent); +#if defined(ENABLE_LINUXDCO) + dco_event_set(&c->c1.tuntap->dco, mtcp->es, MTCP_DCO); +#endif #ifdef ENABLE_MANAGEMENT if (management) @@ -393,6 +400,20 @@ multi_tcp_wait_lite(struct multi_context *m, struct multi_instance *mi, const in tv_clear(&c->c2.timeval); /* ZERO-TIMEOUT */ +#if defined(ENABLE_LINUXDCO) + if (mi && mi->context.c2.link_socket->info.dco_installed) + { + /* If we got a socket that has been handed over to the kernel + * we must not call the normal socket function to figure out + * if it is readable or writable */ + /* Assert that we only have the DCO exptected flags */ + ASSERT(action & (TA_SOCKET_READ | TA_SOCKET_WRITE)); + + /* We are always ready! */ + return action; + } +#endif + switch (action) { case TA_TUN_READ: @@ -516,7 +537,10 @@ multi_tcp_dispatch(struct multi_context *m, struct multi_instance *mi, const int case TA_INITIAL: ASSERT(mi); - multi_tcp_set_global_rw_flags(m, mi); + if (!mi->context.c2.link_socket->info.dco_installed) + { + multi_tcp_set_global_rw_flags(m, mi); + } multi_process_post(m, mi, mpp_flags); break; @@ -566,7 +590,10 @@ multi_tcp_post(struct multi_context *m, struct multi_instance *mi, const int act } else { - multi_tcp_set_global_rw_flags(m, mi); + if (!c->c2.link_socket->info.dco_installed) + { + multi_tcp_set_global_rw_flags(m, mi); + } } break; @@ -623,23 +650,22 @@ multi_tcp_action(struct multi_context *m, struct multi_instance *mi, int action, /* * Dispatch the action */ - { - struct multi_instance *touched = multi_tcp_dispatch(m, mi, action); + struct multi_instance *touched = multi_tcp_dispatch(m, mi, action); - /* - * Signal received or TCP connection - * reset by peer? - */ - if (touched && IS_SIG(&touched->context)) + /* + * Signal received or TCP connection + * reset by peer? + */ + if (touched && IS_SIG(&touched->context)) + { + if (mi == touched) { - if (mi == touched) - { - mi = NULL; - } - multi_close_instance_on_signal(m, touched); + mi = NULL; } + multi_close_instance_on_signal(m, touched); } + /* * If dispatch produced any pending output * for a particular instance, point to @@ -737,6 +763,13 @@ multi_tcp_process_io(struct multi_context *m) multi_tcp_action(m, mi, TA_INITIAL, false); } } +#if defined(ENABLE_LINUXDCO) + /* incoming data on DCO? */ + else if (e->arg == MTCP_DCO) + { + multi_process_incoming_dco(m); + } +#endif /* signal received? */ else if (e->arg == MTCP_SIG) { diff --git a/src/openvpn/mudp.c b/src/openvpn/mudp.c index 07e2caae..1fc391fb 100644 --- a/src/openvpn/mudp.c +++ b/src/openvpn/mudp.c @@ -227,6 +227,19 @@ multi_process_io_udp(struct multi_context *m) multi_process_file_closed(m, mpp_flags); } #endif +#ifdef ENABLE_LINUXDCO + else if (status & DCO_READ) + { + if(!IS_SIG(&m->top)) + { + bool ret = true; + while (ret) + { + ret = multi_process_incoming_dco(m); + } + } + } +#endif } /* diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c index 103e882e..650804ea 100644 --- a/src/openvpn/multi.c +++ b/src/openvpn/multi.c @@ -51,6 +51,10 @@ #include "crypto_backend.h" #include "ssl_util.h" +#include "dco.h" + +static void multi_signal_instance(struct multi_context *m, struct multi_instance *mi, const int sig); + /*#define MULTI_DEBUG_EVENT_LOOP*/ @@ -519,6 +523,9 @@ multi_del_iroutes(struct multi_context *m, { const struct iroute *ir; const struct iroute_ipv6 *ir6; + + dco_delete_iroutes(m, mi); + if (TUNNEL_TYPE(mi->context.c1.tuntap) == DEV_TYPE_TUN) { for (ir = mi->context.options.iroutes; ir != NULL; ir = ir->next) @@ -1224,16 +1231,17 @@ multi_learn_in_addr_t(struct multi_context *m, addr.netbits = (uint8_t) netbits; } - { - struct multi_instance *owner = multi_learn_addr(m, mi, &addr, 0); + struct multi_instance *owner = multi_learn_addr(m, mi, &addr, 0); #ifdef ENABLE_MANAGEMENT - if (management && owner) - { - management_learn_addr(management, &mi->context.c2.mda_context, &addr, primary); - } -#endif - return owner; + if (management && owner) + { + management_learn_addr(management, &mi->context.c2.mda_context, &addr, primary); } +#endif + + dco_install_iroute(m, mi, &addr, primary); + + return owner; } static struct multi_instance * @@ -1257,16 +1265,20 @@ multi_learn_in6_addr(struct multi_context *m, mroute_addr_mask_host_bits( &addr ); } - { - struct multi_instance *owner = multi_learn_addr(m, mi, &addr, 0); + struct multi_instance *owner = multi_learn_addr(m, mi, &addr, 0); #ifdef ENABLE_MANAGEMENT - if (management && owner) - { - management_learn_addr(management, &mi->context.c2.mda_context, &addr, primary); - } + if (management && owner) + { + management_learn_addr(management, &mi->context.c2.mda_context, &addr, primary); + } #endif - return owner; + if (!primary) + { + /* We do not want to install IP -> IP dev ovpn-dco0 */ + dco_install_iroute(m, mi, &addr, primary); } + + return owner; } /* @@ -1764,6 +1776,15 @@ multi_client_set_protocol_options(struct context *c) { tls_multi->use_peer_id = true; } + else if (dco_enabled(o)) + { + msg(M_INFO, "Client does not support DATA_V2. Data channel offloaing " + "requires DATA_V2. Dropping client."); + auth_set_client_reason(tls_multi, "Data channel negotiation " + "failed (missing DATA_V2)"); + return false; + } + if (proto & IV_PROTO_REQUEST_PUSH) { c->c2.push_request_received = true; @@ -1775,7 +1796,6 @@ multi_client_set_protocol_options(struct context *c) o->data_channel_crypto_flags |= CO_USE_TLS_KEY_MATERIAL_EXPORT; } #endif - /* Select cipher if client supports Negotiable Crypto Parameters */ /* if we have already created our key, we cannot *change* our own @@ -2271,12 +2291,127 @@ cleanup: return ret; } +#if defined(ENABLE_LINUXDCO) +#include + +static struct sockaddr * +multi_dco_get_localaddr(struct multi_context *m, struct multi_instance *mi, + struct gc_arena *gc) +{ + struct context *c = &mi->context; + + if ((c->options.sockflags & SF_USE_IP_PKTINFO)) + { + struct link_socket_actual *actual = &c->c2.link_socket_info->lsa->actual; + + switch(actual->dest.addr.sa.sa_family) + { + case AF_INET: + { + struct sockaddr_in *sock_in4; + ALLOC_OBJ_CLEAR_GC(sock_in4, struct sockaddr_in, gc); + sock_in4->sin_addr = actual->pi.in4.ipi_addr; + sock_in4->sin_family = AF_INET; + return (struct sockaddr *) sock_in4; + } + case AF_INET6: + { + struct sockaddr_in6 *sock_in6; + ALLOC_OBJ_CLEAR_GC(sock_in6, struct sockaddr_in6, gc); + sock_in6->sin6_addr = actual->pi.in6.ipi6_addr; + sock_in6->sin6_family = AF_INET6; + return (struct sockaddr *) sock_in6; + } + default: + ASSERT(0); + } + } + else + { + return NULL; + } +} + +static bool +multi_dco_add_new_peer(struct multi_context *m, struct multi_instance *mi) +{ + struct context *c = &mi->context; + + int peer_id = mi->context.c2.tls_multi->peer_id; + int sd = c->c2.link_socket->sd; + struct sockaddr *remoteaddr; + struct sockaddr *local; + + if (c->mode == CM_CHILD_TCP) + { + /* the remote address will be inferred from the TCP socket endpoint */ + remoteaddr = NULL; + } + else + { + ASSERT(c->c2.link_socket_info->connection_established); + remoteaddr = &c->c2.link_socket_info->lsa->actual.dest.addr.sa; + } + + struct in_addr remote_ip4 = { 0 }; + struct in6_addr *remote_addr6 = NULL; + struct in_addr *remote_addr4 = NULL; + struct gc_arena gc = gc_new(); + + /* In server mode we need to fetch the remote addresses from the push config */ + if (c->c2.push_ifconfig_defined) + { + remote_ip4.s_addr = htonl(c->c2.push_ifconfig_local); + remote_addr4 = &remote_ip4; + } + if (c->c2.push_ifconfig_ipv6_defined) + { + remote_addr6 = &c->c2.push_ifconfig_ipv6_local; + } + + local = multi_dco_get_localaddr(m, mi, &gc); + + if (dco_new_peer(c->c1.tuntap, peer_id, sd, local, remoteaddr, + remote_addr4, remote_addr6) != 0) + { + gc_free(&gc); + return false; + } + + c->c2.tls_multi->dco_peer_added = true; + + dco_do_key_dance(c->c1.tuntap, c->c2.tls_multi, c->options.ciphername); + + if (c->options.ping_send_timeout) + { + ovpn_set_peer(c->c1.tuntap, peer_id, c->options.ping_send_timeout, + c->options.ping_rec_timeout); + } + + if (c->mode == CM_CHILD_TCP ) + { + multi_tcp_dereference_instance(m->mtcp, mi); + if (close(sd)) + { + msg(D_DCO|M_ERRNO, "error closing TCP socket after DCO handover"); + } + c->c2.link_socket->info.dco_installed = true; + c->c2.link_socket->sd = SOCKET_UNDEFINED; + } + + gc_free(&gc); + + return true; +} +#endif + /** * Generates the data channel keys */ static bool -multi_client_generate_tls_keys(struct context *c) +multi_client_generate_tls_keys(struct multi_context *m, struct multi_instance *mi) { + struct context *c = &mi->context; struct frame *frame_fragment = NULL; #ifdef ENABLE_FRAGMENT if (c->options.ce.fragment) @@ -2293,6 +2428,13 @@ multi_client_generate_tls_keys(struct context *c) return false; } +#if defined(ENABLE_LINUXDCO) + if (dco_enabled(&c->options) && !multi_dco_add_new_peer(m, mi)) + { + return false; + } +#endif + return true; } @@ -2399,7 +2541,7 @@ multi_client_connect_late_setup(struct multi_context *m, } /* Generate data channel keys only if setting protocol options * has not failed */ - else if (!multi_client_generate_tls_keys(&mi->context)) + else if (!multi_client_generate_tls_keys(m, mi)) { mi->context.c2.tls_multi->multi_state = CAS_FAILED; } @@ -2659,6 +2801,14 @@ multi_connection_established(struct multi_context *m, struct multi_instance *mi) (*cur_handler_index)++; } + /* Check if we have forbidding options in the current mode */ + if (dco_enabled(&mi->context.options) + && check_option_conflict_dco(D_MULTI_ERRORS, &mi->context.options)) + { + msg(D_MULTI_ERRORS, "MULTI: client has been rejected due to incompatible options"); + cc_succeeded = false; + } + if (cc_succeeded) { multi_client_connect_late_setup(m, mi, *option_types_found); @@ -3077,6 +3227,98 @@ done: gc_free(&gc); } + +#if defined(ENABLE_LINUXDCO) + +static void +process_incoming_dco_packet(struct multi_context *m, struct multi_instance *mi, dco_context_t *dco) +{ + struct buffer orig_buf = mi->context.c2.buf; + int peer_id = dco->dco_meesage_peer_id; + + mi->context.c2.buf = dco->dco_packet_in; + + multi_process_incoming_link(m, mi, 0); + + mi->context.c2.buf = orig_buf; + if (BLEN(&dco->dco_packet_in) < 1) + { + msg(D_DCO, "Received too short packet for peer %d" , peer_id); + goto done; + } + + uint8_t *ptr = BPTR(&dco->dco_packet_in); + uint8_t op = ptr[0] >> P_OPCODE_SHIFT; + if (op == P_DATA_V2 || op == P_DATA_V2) + { + msg(D_DCO, "DCO: received data channel packet for peer %d" , peer_id); + goto done; + } + done: + buf_init(&dco->dco_packet_in, 0); +} + +static void +process_incoming_del_peer(struct multi_context *m, struct multi_instance *mi, dco_context_t *dco) +{ + const char *reason = "(unknown reason by ovpn-dco)"; + switch (dco->dco_del_peer_reason) + { + case OVPN_DEL_PEER_REASON_EXPIRED: + reason = "ovpn-dco: ping expired"; + break; + case OVPN_DEL_PEER_REASON_TRANSPORT_ERROR: + reason = "ovpn-dco: transport error"; + break; + case OVPN_DEL_PEER_REASON_USERSPACE: + /* This very likely ourselves but might be another process, so + * still process it */ + reason = "ovpn-dco: userspace request"; + break; + } + + /* When kernel already deleted the peer, the socket is no longer + * installed and we don't need to cleanup the state in the kernel */ + mi->context.c2.tls_multi->dco_peer_added = false; + mi->context.sig->signal_text = reason; + multi_signal_instance(m, mi, SIGTERM); + +} + +bool +multi_process_incoming_dco(struct multi_context *m) +{ + dco_context_t *dco = &m->top.c1.tuntap->dco; + + struct multi_instance *mi = NULL; + + int ret = ovpn_do_read_dco(&m->top.c1.tuntap->dco); + + int peer_id = dco->dco_meesage_peer_id; + + if ((peer_id >= 0) && (peer_id < m->max_clients) && (m->instances[peer_id])) + { + mi = m->instances[peer_id]; + if (dco->dco_message_type == OVPN_CMD_PACKET) + { + process_incoming_dco_packet(m, mi, dco); + } + else if (dco->dco_message_type == OVPN_CMD_DEL_PEER) + { + process_incoming_del_peer(m, mi, dco); + } + } + else + { + msg(D_DCO, "Received packet for peer-id unknown to OpenVPN: %d" , peer_id); + } + + dco->dco_message_type = 0; + dco->dco_meesage_peer_id = -1; + return ret > 0; +} +#endif + /* * Process packets in the TCP/UDP socket -> TUN/TAP interface direction, * i.e. client -> server direction. diff --git a/src/openvpn/multi.h b/src/openvpn/multi.h index 6e85c21c..71883ee5 100644 --- a/src/openvpn/multi.h +++ b/src/openvpn/multi.h @@ -98,7 +98,9 @@ struct client_connect_defer_state * server-mode. */ struct multi_instance { - struct schedule_entry se; /* this must be the first element of the structure */ + struct schedule_entry se; /* this must be the first element of the structure, + * We cast between this and schedule_entry so the + * beginning of the struct must be identical */ struct gc_arena gc; bool halt; int refcount; @@ -308,6 +310,8 @@ void multi_process_float(struct multi_context *m, struct multi_instance *mi); bool multi_process_post(struct multi_context *m, struct multi_instance *mi, const unsigned int flags); +bool multi_process_incoming_dco(struct multi_context *m); + /**************************************************************************/ /** * Demultiplex and process a packet received over the external network diff --git a/src/openvpn/networking.h b/src/openvpn/networking.h index 2f0ee160..cb57802b 100644 --- a/src/openvpn/networking.h +++ b/src/openvpn/networking.h @@ -27,6 +27,7 @@ struct context; #ifdef ENABLE_SITNL #include "networking_sitnl.h" +#include "dco.h" #elif ENABLE_IPROUTE #include "networking_iproute2.h" #else diff --git a/src/openvpn/networking_linuxdco.c b/src/openvpn/networking_linuxdco.c new file mode 100644 index 00000000..ca6284e7 --- /dev/null +++ b/src/openvpn/networking_linuxdco.c @@ -0,0 +1,848 @@ +/* + * Interface to linux dco networking code + * + * Copyright (C) 2020 Antonio Quartulli + * Copyright (C) 2020 Arne Schwabe + * Copyright (C) 2020 OpenVPN Inc + * + * 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 + +#if defined(ENABLE_LINUXDCO) + +#include "syshead.h" + +#include "errlevel.h" +#include "buffer.h" +#include "networking.h" + +#include "socket.h" +#include "tun.h" +#include "ssl.h" +#include "fdmisc.h" +#include "ssl_verify.h" + +#include + +#include +#include +#include +#include +#include + + +/* libnl < 3.5.0 does not set the NLA_F_NESTED on its own, therefore we + * have to explicitly do it to prevent the kernel from failing upon + * parsing of the message + */ +#define nla_nest_start(_msg, _type) \ + nla_nest_start(_msg, (_type) | NLA_F_NESTED) + +static int ovpn_get_mcast_id(dco_context_t *dco); + +void dco_check_key_ctx(const struct key_ctx_bi *key); + +typedef int (*ovpn_nl_cb)(struct nl_msg *msg, void *arg); + +int +resolve_ovpn_netlink_id(int msglevel) +{ + int ret; + struct nl_sock* nl_sock = nl_socket_alloc(); + + ret = genl_connect(nl_sock); + if (ret) + { + msg(msglevel, "Cannot connect to generic netlink: %s", + nl_geterror(ret)); + goto err_sock; + } + set_cloexec(nl_socket_get_fd(nl_sock)); + + ret = genl_ctrl_resolve(nl_sock, OVPN_NL_NAME); + if (ret < 0) + { + msg(msglevel, "Cannot find ovpn_dco netlink component: %s", + nl_geterror(ret)); + } + +err_sock: + nl_socket_free(nl_sock); + return ret; +} + +static struct nl_msg *ovpn_dco_nlmsg_create(dco_context_t *dco, + enum ovpn_nl_commands cmd) +{ + struct nl_msg *nl_msg = nlmsg_alloc(); + if (!nl_msg) + { + msg(M_ERR, "cannot allocate netlink message"); + return NULL; + } + + genlmsg_put(nl_msg, 0, 0, dco->ovpn_dco_id, 0, 0, cmd, 0); + NLA_PUT_U32(nl_msg, OVPN_ATTR_IFINDEX, dco->ifindex); + + return nl_msg; +nla_put_failure: + nlmsg_free(nl_msg); + msg(M_INFO, "cannot put into netlink message"); + return NULL; +} + +static int ovpn_nl_recvmsgs(dco_context_t *dco, const char *prefix) +{ + int ret = nl_recvmsgs(dco->nl_sock, dco->nl_cb); + + switch (ret) { + case -NLE_INTR: + msg(M_WARN, "%s: netlink received interrupt due to signal - ignoring", prefix); + break; + case -NLE_NOMEM: + msg(M_ERR, "%s: netlink out of memory error", prefix); + break; + case -M_ERR: + msg(M_WARN, "%s: netlink reports blocking read - aborting wait", prefix); + break; + case -NLE_NODEV: + msg(M_ERR, "%s: netlink reports device not found:", prefix); + break; + case -NLE_OBJ_NOTFOUND: + msg(M_INFO, "%s: netlink reports object not found, ovpn-dco unloaded?", prefix); + break; + default: + if (ret) + { + msg(M_NONFATAL|M_ERRNO, "%s: netlink reports error (%d): %s", prefix, ret, nl_geterror(-ret)); + } + break; + } + + return ret; +} + +/** + * Send a preprared netlink message and registers cb as callback if non-null. + * + * The method will also free nl_msg + * @param dco The dco context to use + * @param nl_msg the message to use + * @param cb An optional callback if the caller expects an answers\ + * @param prefix A prefix to report in the error message to give the user context + * @return status of sending the message + */ +static int +ovpn_nl_msg_send(dco_context_t *dco, struct nl_msg *nl_msg, ovpn_nl_cb cb, + const char* prefix) +{ + dco->status = 1; + + if (cb) + { + nl_cb_set(dco->nl_cb, NL_CB_VALID, NL_CB_CUSTOM, cb, dco); + } + else + { + nl_cb_set(dco->nl_cb, NL_CB_VALID, NL_CB_CUSTOM, NULL, dco); + } + + nl_send_auto(dco->nl_sock, nl_msg); + + while (dco->status == 1) + { + ovpn_nl_recvmsgs(dco, prefix); + } + + if (dco->status < 0) + { + msg(M_INFO, "%s: failed to send netlink message: %s (%d)", + prefix, strerror(-dco->status), dco->status); + } + + return dco->status; +} + +struct sockaddr * +mapped_v4_to_v6(struct sockaddr *sock, struct gc_arena *gc) +{ + struct sockaddr_in6 *sock6 = ((struct sockaddr_in6 *)sock); + if (sock->sa_family == AF_INET6 && + memcmp(&sock6->sin6_addr, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff", 12)==0) + { + + struct sockaddr_in* sock4; + ALLOC_OBJ_CLEAR_GC(sock4, struct sockaddr_in, gc); + memcpy (&sock4->sin_addr, sock6->sin6_addr.s6_addr +12, 4); + sock4->sin_port = sock6->sin6_port; + sock4->sin_family = AF_INET; + return (struct sockaddr *) sock4; + } + return sock; +} + +int dco_new_peer(struct tuntap *tt, unsigned int peerid, int sd, + struct sockaddr *localaddr, struct sockaddr *remoteaddr, + struct in_addr *remote_in4, struct in6_addr *remote_in6) +{ + msg(D_DCO_DEBUG, "%s: peer-id %d, fd %d", __func__, peerid, sd); + + struct gc_arena gc = gc_new(); + struct nl_msg *nl_msg = ovpn_dco_nlmsg_create(&tt->dco, OVPN_CMD_NEW_PEER); + struct nlattr *attr = nla_nest_start(nl_msg, OVPN_ATTR_NEW_PEER); + int ret = -EMSGSIZE; + + NLA_PUT_U32(nl_msg, OVPN_NEW_PEER_ATTR_PEER_ID, peerid); + NLA_PUT_U32(nl_msg, OVPN_NEW_PEER_ATTR_SOCKET, sd); + + /* Set the remote endpoint if defined (for UDP) */ + if (remoteaddr) + { + remoteaddr = mapped_v4_to_v6(remoteaddr, &gc); + int alen = af_addr_size(remoteaddr->sa_family); + + NLA_PUT(nl_msg, OVPN_NEW_PEER_ATTR_SOCKADDR_REMOTE, alen, remoteaddr); + } + + if (localaddr) + { + localaddr = mapped_v4_to_v6(localaddr, &gc); + if (localaddr->sa_family == AF_INET) + { + NLA_PUT(nl_msg, OVPN_NEW_PEER_ATTR_LOCAL_IP, sizeof(struct in_addr), + &((struct sockaddr_in *)localaddr)->sin_addr); + } + else if (localaddr->sa_family == AF_INET6) + { + NLA_PUT(nl_msg, OVPN_NEW_PEER_ATTR_LOCAL_IP, sizeof(struct in6_addr), + &((struct sockaddr_in6 *)localaddr)->sin6_addr); + } + } + + /* Set the primary VPN IP addresses of the peer */ + if (remote_in4) + { + NLA_PUT_U32(nl_msg, OVPN_NEW_PEER_ATTR_IPV4, remote_in4->s_addr); + } + if (remote_in6) + { + NLA_PUT(nl_msg, OVPN_NEW_PEER_ATTR_IPV6, sizeof(struct in6_addr), + remote_in6); + } + nla_nest_end(nl_msg, attr); + + + ret = ovpn_nl_msg_send(&tt->dco, nl_msg, NULL, __func__); + +nla_put_failure: + nlmsg_free(nl_msg); + gc_free(&gc); + return ret; +} + +static int +ovpn_nl_cb_finish(struct nl_msg (*msg)__attribute__((unused)), void *arg) +{ + int *status = arg; + + *status = 0; + return NL_SKIP; +} + +static int +ovpn_nl_cb_error(struct sockaddr_nl (*nla)__attribute__((unused)), + struct nlmsgerr *err, void *arg) +{ + struct nlmsghdr *nlh = (struct nlmsghdr *)err - 1; + struct nlattr *tb_msg[NLMSGERR_ATTR_MAX + 1]; + int len = nlh->nlmsg_len; + struct nlattr *attrs; + int *ret = arg; + int ack_len = sizeof(*nlh) + sizeof(int) + sizeof(*nlh); + + *ret = err->error; + + if (!(nlh->nlmsg_flags & NLM_F_ACK_TLVS)) + return NL_STOP; + + if (!(nlh->nlmsg_flags & NLM_F_CAPPED)) + ack_len += err->msg.nlmsg_len - sizeof(*nlh); + + if (len <= ack_len) + return NL_STOP; + + attrs = (void *)((unsigned char *)nlh + ack_len); + len -= ack_len; + + nla_parse(tb_msg, NLMSGERR_ATTR_MAX, attrs, len, NULL); + if (tb_msg[NLMSGERR_ATTR_MSG]) { + len = strnlen((char *)nla_data(tb_msg[NLMSGERR_ATTR_MSG]), + nla_len(tb_msg[NLMSGERR_ATTR_MSG])); + msg(M_WARN, "kernel error: %*s\n", len, + (char *)nla_data(tb_msg[NLMSGERR_ATTR_MSG])); + } + + return NL_STOP; +} + +static void +ovpn_dco_init_netlink(dco_context_t *dco) +{ + dco->ovpn_dco_id = resolve_ovpn_netlink_id(M_ERR); + + dco->nl_sock = nl_socket_alloc(); + + + if (!dco->nl_sock) + { + msg(M_ERR, "Cannot create netlink socket"); + } + + /* TODO: Why are we setting this buffer size? */ + nl_socket_set_buffer_size(dco->nl_sock, 8192, 8192); + + int ret = genl_connect(dco->nl_sock); + if (ret) + { + msg(M_ERR, "Cannot connect to generic netlink: %s", + nl_geterror(ret)); + } + + set_cloexec(nl_socket_get_fd(dco->nl_sock)); + + dco->nl_cb = nl_cb_alloc(NL_CB_DEFAULT); + if (!dco->nl_cb) + { + msg(M_ERR, "failed to allocate netlink callback"); + } + + nl_socket_set_cb(dco->nl_sock, dco->nl_cb); + + nl_cb_err(dco->nl_cb, NL_CB_CUSTOM, ovpn_nl_cb_error, &dco->status); + nl_cb_set(dco->nl_cb, NL_CB_FINISH, NL_CB_CUSTOM, ovpn_nl_cb_finish, + &dco->status); + nl_cb_set(dco->nl_cb, NL_CB_ACK, NL_CB_CUSTOM, ovpn_nl_cb_finish, + &dco->status); + + /* The async PACKET messages confuse libnl and it will drop them with + * wrong sequence numbers (NLE_SEQ_MISMATCH), so disable libnl's sequence + * number check */ + nl_socket_disable_seq_check(dco->nl_sock); +} + +static void +ovpn_dco_uninit_netlink(dco_context_t *dco) +{ + nl_socket_free(dco->nl_sock); + dco->nl_sock = NULL; + + /* Decrease reference count */ + nl_cb_put(dco->nl_cb); + + memset(dco, 0, sizeof(*dco)); +} + +static void ovpn_dco_register(dco_context_t *dco) +{ + msg(D_DCO_DEBUG, __func__); + ovpn_get_mcast_id(dco); + + if (dco->ovpn_dco_mcast_id < 0) + { + msg(M_ERR, "cannot get mcast group: %s", nl_geterror(dco->ovpn_dco_mcast_id)); + } + + /* Register for Ovpn dco specific messages */ + int ret = nl_socket_add_membership(dco->nl_sock, dco->ovpn_dco_mcast_id); + if (ret) + { + msg(M_ERR, "%s: failed to join groups: %d", __func__, ret); + } + + struct nl_msg *nl_msg = ovpn_dco_nlmsg_create(dco, OVPN_CMD_REGISTER_PACKET); + if (!nl_msg) + { + msg(M_ERR, "%s: cannot allocate message to register for control packets", + __func__); + } + + ret = ovpn_nl_msg_send(dco, nl_msg, NULL, __func__); + if (ret) + { + msg(M_ERR, "%s: failed to register for control packets: %d", __func__, + ret); + } + nlmsg_free(nl_msg); +} + +void +open_tun_dco(struct tuntap *tt, const char* dev) +{ + msg(D_DCO_DEBUG, __func__); + ASSERT(tt->type == DEV_TYPE_TUN); + + ovpn_dco_init_netlink(&tt->dco); + + if (!strcmp(dev, "tun")) + { + /* If no specific name has been requested use an auto-assigned name */ + dev = NULL; + } + + tt->dco.ifindex = net_iface_new(dev, "ovpn-dco"); + + char if_name[IFNAMSIZ]; + if(!if_indextoname(tt->dco.ifindex, if_name)) + { + msg(M_ERR|M_ERRNO, "Cannot resolve interface name for dco interface: "); + } + tt->actual_name = string_alloc(if_name, NULL); + uint8_t *dcobuf = malloc(65536); + buf_set_write(&tt->dco.dco_packet_in, dcobuf, 65536); + tt->dco.dco_meesage_peer_id = -1; + + ovpn_dco_register(&tt->dco); +} + +void +close_tun_dco(struct tuntap *tt) +{ + msg(D_DCO_DEBUG, __func__); + + net_iface_del_index(tt->dco.ifindex); + ovpn_dco_uninit_netlink(&tt->dco); + free(tt->dco.dco_packet_in.data); +} + +int dco_swap_keys(struct tuntap *tt, unsigned int peerid) +{ + msg(D_DCO_DEBUG, "%s: peer-id %d", __func__, peerid); + + struct nl_msg *nl_msg = ovpn_dco_nlmsg_create(&tt->dco, OVPN_CMD_SWAP_KEYS); + if (!nl_msg) + return -ENOMEM; + + struct nlattr *attr = nla_nest_start(nl_msg, OVPN_ATTR_SWAP_KEYS); + int ret = -EMSGSIZE; + NLA_PUT_U32(nl_msg, OVPN_SWAP_KEYS_ATTR_PEER_ID, peerid); + nla_nest_end(nl_msg, attr); + + ret = ovpn_nl_msg_send(&tt->dco, nl_msg, NULL, __func__); + +nla_put_failure: + nlmsg_free(nl_msg); + return ret; +} + + +int dco_del_peer(struct tuntap *tt, unsigned int peerid) +{ + msg(D_DCO_DEBUG, "%s: peer-id %d", __func__, peerid); + + struct nl_msg *nl_msg = ovpn_dco_nlmsg_create(&tt->dco, OVPN_CMD_DEL_PEER); + if (!nl_msg) + return -ENOMEM; + + struct nlattr *attr = nla_nest_start(nl_msg, OVPN_ATTR_DEL_PEER); + int ret = -EMSGSIZE; + NLA_PUT_U32(nl_msg, OVPN_DEL_PEER_ATTR_PEER_ID, peerid); + nla_nest_end(nl_msg, attr); + + ret = ovpn_nl_msg_send(&tt->dco, nl_msg, NULL, __func__); + +nla_put_failure: + nlmsg_free(nl_msg); + return ret; +} + + +int +dco_del_key(struct tuntap *tt, unsigned int peerid, ovpn_key_slot_t slot) +{ + msg(D_DCO_DEBUG, "%s: peer-id %d, slot %d", __func__, peerid, slot); + + struct nl_msg *nl_msg = ovpn_dco_nlmsg_create(&tt->dco, OVPN_CMD_DEL_KEY); + if (!nl_msg) + return -ENOMEM; + + struct nlattr *attr = nla_nest_start(nl_msg, OVPN_ATTR_DEL_KEY); + int ret = -EMSGSIZE; + NLA_PUT_U32(nl_msg, OVPN_DEL_KEY_ATTR_PEER_ID, peerid); + NLA_PUT_U8(nl_msg, OVPN_DEL_KEY_ATTR_KEY_SLOT, slot); + nla_nest_end(nl_msg, attr); + + ret = ovpn_nl_msg_send(&tt->dco, nl_msg, NULL, __func__); + +nla_put_failure: + nlmsg_free(nl_msg); + return ret; +} + +int +dco_new_key(struct tuntap *tt, unsigned int peerid, ovpn_key_slot_t slot, + struct key_state *ks, const char* ciphername) +{ + msg(D_DCO_DEBUG, "%s: slot %d, key-id %d, peer-id %d, cipher %s", + __func__, slot, ks->key_id, peerid, ciphername); + const int nonce_len = 8; + + struct key_ctx_bi *key = &ks->crypto_options.key_ctx_bi; + + dco_check_key_ctx(key); + + struct nl_msg *nl_msg = ovpn_dco_nlmsg_create(&tt->dco, OVPN_CMD_NEW_KEY); + if (!nl_msg) + return -ENOMEM; + + int dco_cipher = get_dco_cipher(ciphername); + ASSERT(dco_cipher >= 0); + + + struct nlattr *attr = nla_nest_start(nl_msg, OVPN_ATTR_NEW_KEY); + int ret = -EMSGSIZE; + NLA_PUT_U32(nl_msg, OVPN_NEW_KEY_ATTR_PEER_ID, peerid); + NLA_PUT_U8(nl_msg, OVPN_NEW_KEY_ATTR_KEY_SLOT, slot); + NLA_PUT_U8(nl_msg, OVPN_NEW_KEY_ATTR_KEY_ID, ks->key_id); + + NLA_PUT_U16(nl_msg, OVPN_NEW_KEY_ATTR_CIPHER_ALG, dco_cipher); + + if (dco_cipher != OVPN_CIPHER_ALG_NONE) + { + size_t key_len = cipher_kt_key_size(cipher_kt_get(ciphername)); + struct nlattr *key_enc = nla_nest_start(nl_msg, OVPN_NEW_KEY_ATTR_ENCRYPT_KEY); + NLA_PUT(nl_msg, OVPN_KEY_DIR_ATTR_CIPHER_KEY, key_len, key->encrypt.aead_key); + NLA_PUT(nl_msg, OVPN_KEY_DIR_ATTR_NONCE_TAIL, nonce_len, + key->encrypt.implicit_iv); + nla_nest_end(nl_msg, key_enc); + + struct nlattr *key_dec = nla_nest_start(nl_msg, OVPN_NEW_KEY_ATTR_DECRYPT_KEY); + NLA_PUT(nl_msg, OVPN_KEY_DIR_ATTR_CIPHER_KEY, key_len, key->decrypt.aead_key); + NLA_PUT(nl_msg, OVPN_KEY_DIR_ATTR_NONCE_TAIL, nonce_len, + key->decrypt.implicit_iv); + nla_nest_end(nl_msg, key_dec); + } + else + { + /* Check that --auth is disabled. Normally, we would catch this + * inconsistency earlier but since the "none" is only for debug and + * requires manual editing of DCO_SUPPORTED_CIPHERS, it should be fine + * to abort here */ + if (key->encrypt.hmac != NULL) + { + msg(M_FATAL, "FATAL: DCO with cipher none requires --auth none"); + } + /* ovpn-dco needs empty encrypt/decrypt keys with cipher none */ + struct nlattr *key_enc = nla_nest_start(nl_msg, + OVPN_NEW_KEY_ATTR_ENCRYPT_KEY); + NLA_PUT(nl_msg, OVPN_KEY_DIR_ATTR_CIPHER_KEY, 16, + key->encrypt.aead_key); + nla_nest_end(nl_msg, key_enc); + + struct nlattr *key_dec = nla_nest_start(nl_msg, + OVPN_NEW_KEY_ATTR_DECRYPT_KEY); + NLA_PUT(nl_msg, OVPN_KEY_DIR_ATTR_CIPHER_KEY, 16, + key->decrypt.aead_key); + nla_nest_end(nl_msg, key_dec); + } + nla_nest_end(nl_msg, attr); + + secure_memzero(key->encrypt.aead_key, sizeof (key->encrypt.aead_key)); + secure_memzero(key->decrypt.aead_key, sizeof (key->decrypt.aead_key)); + + ret = ovpn_nl_msg_send(&tt->dco, nl_msg, NULL, __func__); + +nla_put_failure: + nlmsg_free(nl_msg); + return ret; +} + +int ovpn_set_peer(struct tuntap *tt, unsigned int peerid, + unsigned int keepalive_interval, + unsigned int keepalive_timeout) +{ + msg(D_DCO_DEBUG, "%s: peer-id %d, keepalive %d/%d", __func__, peerid, + keepalive_interval, keepalive_timeout); + + struct nl_msg *nl_msg = ovpn_dco_nlmsg_create(&tt->dco, OVPN_CMD_SET_PEER); + if (!nl_msg) + { + return -ENOMEM; + } + + struct nlattr *attr = nla_nest_start(nl_msg, OVPN_ATTR_SET_PEER); + int ret = -EMSGSIZE; + NLA_PUT_U32(nl_msg, OVPN_SET_PEER_ATTR_PEER_ID, peerid); + NLA_PUT_U32(nl_msg, OVPN_SET_PEER_ATTR_KEEPALIVE_INTERVAL, + keepalive_interval); + NLA_PUT_U32(nl_msg, OVPN_SET_PEER_ATTR_KEEPALIVE_TIMEOUT, + keepalive_timeout); + nla_nest_end(nl_msg, attr); + + ret = ovpn_nl_msg_send(&tt->dco, nl_msg, NULL, __func__); + +nla_put_failure: + nlmsg_free(nl_msg); + return ret; +} + +static int mcast_family_handler(struct nl_msg *msg, void *arg) +{ + dco_context_t *dco = arg; + struct nlattr *tb[CTRL_ATTR_MAX + 1]; + struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg)); + + nla_parse(tb, CTRL_ATTR_MAX, genlmsg_attrdata(gnlh, 0), + genlmsg_attrlen(gnlh, 0), NULL); + + if (!tb[CTRL_ATTR_MCAST_GROUPS]) + return NL_SKIP; + + struct nlattr *mcgrp; + int rem_mcgrp; + nla_for_each_nested(mcgrp, tb[CTRL_ATTR_MCAST_GROUPS], rem_mcgrp) + { + struct nlattr *tb_mcgrp[CTRL_ATTR_MCAST_GRP_MAX + 1]; + + nla_parse(tb_mcgrp, CTRL_ATTR_MCAST_GRP_MAX, + nla_data(mcgrp), nla_len(mcgrp), NULL); + + if (!tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME] || + !tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID]) + { + continue; + } + + if (strncmp(nla_data(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME]), + OVPN_NL_MULTICAST_GROUP_PEERS, + nla_len(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME])) != 0) + { + continue; + } + dco->ovpn_dco_mcast_id = nla_get_u32(tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID]); + break; + } + + return NL_SKIP; +} +/** + * Lookup the multicast id for OpenVPN. This method and its help method currently + * hardcode the lookup to OVPN_NL_NAME and OVPN_NL_MULTICAST_GROUP_PEERS but + * extended in the future if we need to lookup more than one mcast id. + */ +static int +ovpn_get_mcast_id(dco_context_t *dco) +{ + dco->ovpn_dco_mcast_id = -ENOENT; + + /* Even though 'nlctrl' is a constant, there seem to be no library + * provided define for it */ + int ctrlid = genl_ctrl_resolve(dco->nl_sock, "nlctrl"); + + struct nl_msg *nl_msg = nlmsg_alloc(); + if (!nl_msg) + { + return -ENOMEM; + } + + genlmsg_put(nl_msg, 0, 0, ctrlid, 0, 0, CTRL_CMD_GETFAMILY, 0); + + int ret = -EMSGSIZE; + NLA_PUT_STRING(nl_msg, CTRL_ATTR_FAMILY_NAME, OVPN_NL_NAME); + + ret = ovpn_nl_msg_send(dco, nl_msg, mcast_family_handler, __func__); + +nla_put_failure: + nlmsg_free(nl_msg); + return ret; +} + +static int ovpn_handle_msg(struct nl_msg *msg, void *arg) +{ + dco_context_t *dco = arg; + + struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg)); + struct nlattr *attrs[OVPN_ATTR_MAX + 1]; + struct nlmsghdr *nlh = nlmsg_hdr(msg); + + if (!genlmsg_valid_hdr(nlh, 0)) + { + msg(D_DCO, "ovpn-dco: invalid header"); + return NL_SKIP; + } + + if (nla_parse(attrs, OVPN_ATTR_MAX, genlmsg_attrdata(gnlh, 0), + genlmsg_attrlen(gnlh, 0), NULL)) + { + msg(D_DCO, "received bogus data from ovpn-dco"); + return NL_SKIP; + } + + if (!attrs[OVPN_ATTR_IFINDEX]) + { + msg(D_DCO, "ovpn-dco: Received message without ifindex"); + return NL_SKIP; + } + + uint32_t ifindex = nla_get_u32(attrs[OVPN_ATTR_IFINDEX]); + if (ifindex != dco->ifindex) + { + msg(D_DCO, "ovpn-dco: received message type %d with mismatched ifindex %d\n", + gnlh->cmd, ifindex); + return NL_SKIP; + } + + switch (gnlh->cmd) { + case OVPN_CMD_DEL_PEER: + { + if (!attrs[OVPN_ATTR_DEL_PEER]) + { + msg(D_DCO, "ovpn-dco: no attributes in OVPN_DEL_PEER message"); + return NL_SKIP; + } + + struct nlattr *dp_attrs[OVPN_DEL_PEER_ATTR_MAX + 1]; + if (nla_parse_nested(dp_attrs, OVPN_DEL_PEER_ATTR_MAX, + attrs[OVPN_ATTR_DEL_PEER], NULL)) + { + msg(D_DCO, "received bogus del peer packet data from ovpn-dco"); + return NL_SKIP; + } + + if (!dp_attrs[OVPN_DEL_PEER_ATTR_REASON]) + { + msg(D_DCO, "ovpn-dco: no reason in DEL_PEER message"); + return NL_SKIP; + } + if (!dp_attrs[OVPN_DEL_PEER_ATTR_PEER_ID]) + { + msg(D_DCO, "ovpn-dco: no peer-id in DEL_PEER message"); + return NL_SKIP; + } + int reason = nla_get_u8(dp_attrs[OVPN_DEL_PEER_ATTR_REASON]); + unsigned int peerid = nla_get_u32(dp_attrs[OVPN_DEL_PEER_ATTR_PEER_ID]); + + msg(D_DCO_DEBUG, "ovpn-dco: received CMD_DEL_PEER, ifindex: %d, peer-id %d, reason: %d", + ifindex, peerid, reason); + dco->dco_meesage_peer_id = peerid; + dco->dco_del_peer_reason = reason; + dco->dco_message_type = OVPN_CMD_DEL_PEER; + + break; + } + case OVPN_CMD_PACKET: + { + if (!attrs[OVPN_ATTR_PACKET]) + { + msg(D_DCO, "ovpn-dco: no packet in OVPN_CMD_PACKET message"); + return NL_SKIP; + } + struct nlattr *pkt_attrs[OVPN_PACKET_ATTR_MAX + 1]; + + if (nla_parse_nested(pkt_attrs, OVPN_PACKET_ATTR_MAX, + attrs[OVPN_ATTR_PACKET], NULL)) + { + msg(D_DCO, "received bogus cmd packet data from ovpn-dco"); + return NL_SKIP; + } + if (!pkt_attrs[OVPN_PACKET_ATTR_PEER_ID]) + { + msg(D_DCO, "ovpn-dco: Received OVPN_CMD_PACKET message without peer id"); + return NL_SKIP; + } + if (!pkt_attrs[OVPN_PACKET_ATTR_PACKET]) + { + msg(D_DCO, "ovpn-dco: Received OVPN_CMD_PACKET message without packet"); + return NL_SKIP; + } + + unsigned int peerid = nla_get_u32(pkt_attrs[OVPN_PACKET_ATTR_PEER_ID]); + + uint8_t *data = nla_data(pkt_attrs[OVPN_PACKET_ATTR_PACKET]); + int len = nla_len(pkt_attrs[OVPN_PACKET_ATTR_PACKET]); + + msg(D_DCO_DEBUG, "ovpn-dco: received OVPN_PACKET_ATTR_PACKET, ifindex: %d peer-id: %d, len %d", + ifindex, peerid, len); + if (BLEN(&dco->dco_packet_in) > 0) + { + msg(D_DCO, "DCO packet buffer still full?!"); + return NL_SKIP; + } + buf_init(&dco->dco_packet_in, 0); + buf_write(&dco->dco_packet_in, data, len); + dco->dco_meesage_peer_id = peerid; + dco->dco_message_type = OVPN_CMD_PACKET; + break; + } + default: + msg(D_DCO, "ovpn-dco: received unknown command: %d", gnlh->cmd); + dco->dco_message_type = 0; + return NL_SKIP; + } + + return NL_OK; +} + +int +ovpn_do_read_dco(struct dco_context *dco) +{ + msg(D_DCO_DEBUG, __func__); + nl_cb_set(dco->nl_cb, NL_CB_VALID, NL_CB_CUSTOM, ovpn_handle_msg, dco); + + return ovpn_nl_recvmsgs(dco, __func__); +} + +int +ovpn_do_write_dco(dco_context_t *dco, int peer_id, struct buffer *buf) +{ + packet_size_type len = BLEN(buf); + dmsg(D_STREAM_DEBUG, "DCO: WRITE %d offset=%d", (int)len, buf->offset); + + msg(D_DCO_DEBUG, "%s: peer-id %d, len=%d", __func__, peer_id, len); + + struct nl_msg *nl_msg = ovpn_dco_nlmsg_create(dco, OVPN_CMD_PACKET); + + if (!nl_msg) + { + return -ENOMEM; + } + + struct nlattr *attr = nla_nest_start(nl_msg, OVPN_ATTR_PACKET); + int ret = -EMSGSIZE; + NLA_PUT_U32(nl_msg, OVPN_PACKET_ATTR_PEER_ID, peer_id); + NLA_PUT(nl_msg, OVPN_PACKET_ATTR_PACKET, len, BSTR(buf)); + nla_nest_end(nl_msg, attr); + + ret = ovpn_nl_msg_send(dco, nl_msg, NULL, __func__); + if (ret) + { + goto nla_put_failure; + } + + /* return the length of the written data in case of success */ + ret = len; + +nla_put_failure: + nlmsg_free(nl_msg); + return ret; +} + +#endif diff --git a/src/openvpn/networking_linuxdco.h b/src/openvpn/networking_linuxdco.h new file mode 100644 index 00000000..be39437e --- /dev/null +++ b/src/openvpn/networking_linuxdco.h @@ -0,0 +1,85 @@ +/* + * Interface to linux dco networking code + * + * Copyright (C) 2020 Antonio Quartulli + * Copyright (C) 2020 Arne Schwabe + * Copyright (C) 2020 OpenVPN Inc + * + * 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 + */ +#ifndef NETWORKING_LINUXDCO_H +#define NETWORKING_LINUXDCO_H +#if defined(ENABLE_LINUXDCO) + +#include +#include +#include + +typedef enum ovpn_key_slot ovpn_key_slot_t; + +#include "event.h" + +#define DCO_IROUTE_METRIC 100 + +#define DCO_SUPPORTED_CIPHERS "AES-128-GCM:AES-256-GCM:AES-192-GCM:CHACHA20-POLY1305" + +struct dco_context { + struct nl_sock *nl_sock; + struct nl_cb *nl_cb; + int status; + + int ovpn_dco_id; + int ovpn_dco_mcast_id; + + unsigned int ifindex; + + struct buffer dco_packet_in; + + int dco_message_type; + int dco_meesage_peer_id; + int dco_del_peer_reason; + +}; + +typedef struct dco_context dco_context_t; + + +/** + * @brief resolves the netlink ID for ovpn-dco + * + * This function queries the kernel via a netlink socket + * whether the ovpn-dco netlink namespace is available + * + * This function can be used to determine if the kernel + * support DCO offloading. + * + * @return ID on success, negative error code on error + */ +int +resolve_ovpn_netlink_id(int msglevel); + +static inline void +dco_event_set(struct dco_context *dco, + struct event_set *es, + void *arg) { + if (dco && dco->nl_sock) { + event_ctl(es, nl_socket_get_fd(dco->nl_sock), EVENT_READ, arg); + } +} + +int ovpn_do_write_dco(dco_context_t *dco, int peer_id, struct buffer *buf); + +#endif +#endif diff --git a/src/openvpn/openvpn.vcxproj b/src/openvpn/openvpn.vcxproj index 65ee6839..b394cd4a 100644 --- a/src/openvpn/openvpn.vcxproj +++ b/src/openvpn/openvpn.vcxproj @@ -253,8 +253,9 @@ - + + @@ -335,6 +336,7 @@ + diff --git a/src/openvpn/openvpn.vcxproj.filters b/src/openvpn/openvpn.vcxproj.filters index f5fdfcd7..abb591e4 100644 --- a/src/openvpn/openvpn.vcxproj.filters +++ b/src/openvpn/openvpn.vcxproj.filters @@ -39,6 +39,9 @@ Source Files + + Source Files + Source Files @@ -287,6 +290,9 @@ Header Files + + Header Files + Header Files diff --git a/src/openvpn/options.c b/src/openvpn/options.c index ac13412a..a3014415 100644 --- a/src/openvpn/options.c +++ b/src/openvpn/options.c @@ -60,6 +60,7 @@ #include "forward.h" #include "ssl_verify.h" #include "platform.h" +#include "dco.h" #include #include "memdbg.h" @@ -105,6 +106,9 @@ const char title_string[] = #endif #endif " [AEAD]" +#ifdef ENABLE_LINUXDCO + " [DCO]" +#endif " built on " __DATE__ ; @@ -3220,6 +3224,133 @@ options_set_backwards_compatible_options(struct options *o) #endif } +#if defined(ENABLE_DCO) +static bool +check_option_conflict_dco_ce(const struct connection_entry *ce, int msglevel) +{ + if (ce->fragment) + { + msg(msglevel, "Note: --fragment disables data channel offload."); + return true; + } + + if (ce->http_proxy_options) + { + msg(msglevel, "Note: --http-proxy disables data channel offload."); + return true; + } + + if (ce->socks_proxy_server) + { + msg(msglevel, "Note --socks-proxy disable data channel offload."); + return true; + } + + return false; +} + +#if defined(ENABLE_LINUXDCO) +static bool check_option_conflict_dco_platform(int msglevel, const struct options *o) +{ + if (resolve_ovpn_netlink_id(D_TUNTAP_INFO) < 0) + { + msg(D_TUNTAP_INFO, "Note: Kernel support for ovpn-dco missing, disabling " + "data channel offload."); + return true; + } + return false; +} +#endif + +bool check_option_conflict_dco(int msglevel, const struct options *o) +{ + if (o->tuntap_options.disable_dco) + { + /* already disabled by --disable-dco, no need to print warnings */ + return true; + } + + if (check_option_conflict_dco_platform(msglevel, o)) + { + return true; + } + + if (dev_type_enum(o->dev, o->dev_type) != DEV_TYPE_TUN) + { + msg(msglevel, "Note: dev-type not tun, disabling data channel offload."); + return true; + } + + /* At this point the ciphers have already been normalised */ + if (o->enable_ncp_fallback + && !tls_item_in_cipher_list(o->ciphername, DCO_SUPPORTED_CIPHERS)) + { + msg(msglevel, "Note: --data-cipher-fallback with cipher '%s' " + "disables data channel offload.", o->ciphername); + return true; + } + + if (o->connection_list) + { + const struct connection_list *l = o->connection_list; + for (int i = 0; i < l->len; ++i) + { + if (check_option_conflict_dco_ce(l->array[i], msglevel)) + { + return true; + } + } + } + else + { + if (check_option_conflict_dco_ce(&o->ce, msglevel)) + { + return true; + } + } + + if (o->mode == MODE_SERVER && o->topology != TOP_SUBNET) + { + msg(msglevel, "Note: NOT using '--topology subnet' disables data channel offload."); + return true; + } + +#ifdef USE_COMP + if(o->comp.alg != COMP_ALG_UNDEF) + { + msg(msglevel, "Note: Using compression disables data channel offload."); + + if (o->mode == MODE_SERVER && !(o->comp.flags & COMP_F_MIGRATE)) + { + /* We can end up here from the multi.c call, only print the + * note if it is not already enabled */ + msg(msglevel, "Consider using the '--compress migrate' option."); + } + return true; + } +#endif + + struct gc_arena gc = gc_new(); + + + char *tmp_ciphers = string_alloc(o->ncp_ciphers, &gc); + const char *token; + while ((token = strsep(&tmp_ciphers, ":"))) + { + if (!tls_item_in_cipher_list(token, DCO_SUPPORTED_CIPHERS)) + { + msg(msglevel, "Note: cipher '%s' in --data-ciphers is not supported " + "by ovpn-dco, disabling data channel offload.", token); + gc_free(&gc); + return true; + } + } + gc_free(&gc); + + return false; +} +#endif /* if defined(TARGET_LINUX) */ + static void options_postprocess_mutate(struct options *o) { @@ -3306,7 +3437,11 @@ options_postprocess_mutate(struct options *o) "option set). "); o->verify_hash_no_ca = true; } - +#if defined(ENABLE_LINUXDCO) + o->tuntap_options.disable_dco = check_option_conflict_dco(D_DCO, o); +#elif defined(TARGET_LINUX) + o->tuntap_options.disable_dco = true; +#endif /* * Save certain parms before modifying options during connect, especially * when using --pull @@ -5643,6 +5778,12 @@ add_option(struct options *options, options->windows_driver = parse_windows_driver(p[1], M_FATAL); } #endif + else if (streq(p[0], "disable-dco") || streq(p[0], "dco-disable")) + { +#if defined(TARGET_LINUX) + options->tuntap_options.disable_dco = true; +#endif + } else if (streq(p[0], "dev-node") && p[1] && !p[2]) { VERIFY_PERMISSION(OPT_P_GENERAL); diff --git a/src/openvpn/options.h b/src/openvpn/options.h index d4f41cd7..0affc71f 100644 --- a/src/openvpn/options.h +++ b/src/openvpn/options.h @@ -862,4 +862,30 @@ void options_string_import(struct options *options, unsigned int *option_types_found, struct env_set *es); +/** + * Returns whether the current configuration has dco enabled. + */ +#ifdef ENABLE_LINUXDCO +static inline bool +dco_enabled(struct options *o) { return !o->tuntap_options.disable_dco; } + +/** + * Checks whether the options struct has any option that is not supported by + * our current dco implementation. If so it prints a warning at warning level + * for the first conflicting option found and returns false + * @param msglevel the msg level to use to print the warnings + * @param o the optiions struct that hold the options + * @return true if a conflict with dco is detected. + */ +bool +check_option_conflict_dco(int msglevel, const struct options *o); +#else +/* Dummy functions to avoid ifdefs in the other code */ + +static inline bool +dco_enabled(struct options *o) { return false; } + +static inline bool +check_option_conflict_dco(int msglevel, struct options *o) { return false; } +#endif #endif /* ifndef OPTIONS_H */ diff --git a/src/openvpn/socket.h b/src/openvpn/socket.h index cc1e0c36..57142f4e 100644 --- a/src/openvpn/socket.h +++ b/src/openvpn/socket.h @@ -120,6 +120,7 @@ struct link_socket_info sa_family_t af; /* Address family like AF_INET, AF_INET6 or AF_UNSPEC*/ bool bind_ipv6_only; int mtu_changed; /* Set to true when mtu value is changed */ + bool dco_installed; }; /* diff --git a/src/openvpn/ssl.c b/src/openvpn/ssl.c index 4a4859c3..3e0be874 100644 --- a/src/openvpn/ssl.c +++ b/src/openvpn/ssl.c @@ -1880,6 +1880,10 @@ tls_session_update_crypto_params_do_work(struct tls_session *session, init_key_type(&session->opt->key_type, options->ciphername, options->authname, true, true); +#if defined(ENABLE_DCO) + session->opt->key_type.keep_key_data = dco_enabled(options); +#endif + bool packet_id_long_form = cipher_kt_mode_ofb_cfb(session->opt->key_type.cipher); session->opt->crypto_flags &= ~(CO_PACKET_ID_LONG_FORM); if (packet_id_long_form) @@ -2236,7 +2240,7 @@ push_peer_info(struct buffer *buf, struct tls_session *session) { buf_printf(&out, "IV_HWADDR=%s\n", format_hex_ex(rgi.hwaddr, 6, 0, 1, ":", &gc)); } - buf_printf(&out, "IV_SSL=%s\n", get_ssl_library_version() ); + buf_printf(&out, "IV_SSL=%s\n", get_ssl_library_version()); #if defined(_WIN32) buf_printf(&out, "IV_PLAT_VER=%s\n", win32_version_string(&gc, false)); #endif diff --git a/src/openvpn/ssl_common.h b/src/openvpn/ssl_common.h index f851bd2b..0da3c1f2 100644 --- a/src/openvpn/ssl_common.h +++ b/src/openvpn/ssl_common.h @@ -167,6 +167,12 @@ enum auth_deferred_result { ACF_FAILED /**< deferred auth has failed */ }; +enum dco_key_status { + DCO_NOT_INSTALLED, + DCO_INSTALLED_PRIMARY, + DCO_INSTALLED_SECONDARY +}; + /** * Security parameter state of one TLS and data channel %key session. * @ingroup control_processor @@ -240,6 +246,8 @@ struct key_state struct auth_deferred_status plugin_auth; struct auth_deferred_status script_auth; + + enum dco_key_status dco_status; }; /** Control channel wrapping (--tls-auth/--tls-crypt) context */ @@ -634,6 +642,11 @@ struct tls_multi /**< Array of \c tls_session objects * representing control channel * sessions with the remote peer. */ + + /* Only used when DCO is used to remember how many keys we installed + * for this session */ + int dco_keys_installed; + bool dco_peer_added; }; /** gets an item of \c key_state objects in the diff --git a/src/openvpn/ssl_ncp.c b/src/openvpn/ssl_ncp.c index 4b95406e..7f5e6fe8 100644 --- a/src/openvpn/ssl_ncp.c +++ b/src/openvpn/ssl_ncp.c @@ -489,4 +489,4 @@ p2p_mode_ncp(struct tls_multi *multi, struct tls_session *session) multi->use_peer_id, multi->peer_id, common_cipher); gc_free(&gc); -} \ No newline at end of file +} diff --git a/src/openvpn/tun.c b/src/openvpn/tun.c index 75d5eaf7..fb3c2e8b 100644 --- a/src/openvpn/tun.c +++ b/src/openvpn/tun.c @@ -1957,6 +1957,10 @@ open_tun(const char *dev, const char *dev_type, const char *dev_node, struct tun { open_null(tt); } + else if (!tt->options.disable_dco) + { + open_tun_dco(tt, dev); + } else { /* @@ -2206,7 +2210,14 @@ close_tun(struct tuntap *tt, openvpn_net_ctx_t *ctx) net_ctx_reset(ctx); } - close_tun_generic(tt); + if (!tt->options.disable_dco) + { + close_tun_dco(tt); + } + else + { + close_tun_generic(tt); + } free(tt); } diff --git a/src/openvpn/tun.h b/src/openvpn/tun.h index aa1e47b5..d5beb11c 100644 --- a/src/openvpn/tun.h +++ b/src/openvpn/tun.h @@ -40,6 +40,7 @@ #include "misc.h" #include "networking.h" #include "ring_buffer.h" +#include "networking_linuxdco.h" #ifdef _WIN32 #define WINTUN_COMPONENT_ID "wintun" @@ -138,6 +139,7 @@ struct tuntap_options { struct tuntap_options { int txqueuelen; + bool disable_dco; }; #else /* if defined(_WIN32) || defined(TARGET_ANDROID) */ @@ -218,6 +220,8 @@ struct tuntap /* Some TUN/TAP drivers like to be ioctled for mtu * after open */ int post_open_mtu; + + dco_context_t dco; }; static inline bool diff --git a/tests/unit_tests/openvpn/test_networking.c b/tests/unit_tests/openvpn/test_networking.c index 37b97188..20ac9e94 100644 --- a/tests/unit_tests/openvpn/test_networking.c +++ b/tests/unit_tests/openvpn/test_networking.c @@ -1,7 +1,10 @@ #include "config.h" #include "syshead.h" +#include "error.h" #include "networking.h" +#include "mock_msg.h" + static char *iface = "ovpn-dummy0"; @@ -16,8 +19,10 @@ net__iface_up(bool up) static int net__iface_new(const char *name, const char* type) { - printf("CMD: ip link add %s type %s\n", name, type); - return net_iface_new(name, type); + printf("CMD: ip link add type %s\n", type); + int ifidx = net_iface_new(NULL, type); + printf("ifindex: %d\n", ifidx); + return ifidx; } static int