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Re: [Qemu-devel] [PATCH v7] net: L2TPv3 transport
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From: |
Anton Ivanov (antivano) |
|
Subject: |
Re: [Qemu-devel] [PATCH v7] net: L2TPv3 transport |
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Date: |
Thu, 3 Apr 2014 12:56:01 +0000 |
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User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20131103 Icedove/17.0.10 |
On 03/04/14 13:20, Benoît Canet wrote:
> The Monday 31 Mar 2014 à 15:39:19 (+0100), address@hidden wrote :
>> From: Anton Ivanov <address@hidden>
>>
>> This transport allows to connect a QEMU nic to a static Ethernet
>> over L2TPv3 tunnel. The transport supports all options present
>> in the Linux kernel implementation. It allows QEMU to connect
>> to any Linux host running kernel 3.3+, most routers and network
>> devices as well as other QEMU instances.
>>
>> Signed-off-by: Anton Ivanov <address@hidden>
>> ---
> Hi,
>
> On what branch does this patch apply ?
>
> I failed to apply it on master.
v1.7.0
A.
>
> Best regards
>
> Benoît
>
>> Addressed in this release:
>>
>> 1. Back to qemu send_packet instead of direct delivery from the
>> recvmmsg ring. The zero copy off driver rx ring will be reintroduced
>> in a later patch
>>
>> 2. Fixed mismerge of header size handling from our tree
>>
>> 3. Fixed formatting
>>
>>
>> net/Makefile.objs | 1 +
>> net/clients.h | 2 +
>> net/l2tpv3.c | 745
>> +++++++++++++++++++++++++++++++++++++++++++++++++++++
>> net/net.c | 3 +
>> qapi-schema.json | 60 +++++
>> qemu-options.hx | 82 ++++++
>> 6 files changed, 893 insertions(+)
>> create mode 100644 net/l2tpv3.c
>>
>> diff --git a/net/Makefile.objs b/net/Makefile.objs
>> index 4854a14..160214e 100644
>> --- a/net/Makefile.objs
>> +++ b/net/Makefile.objs
>> @@ -2,6 +2,7 @@ common-obj-y = net.o queue.o checksum.o util.o hub.o
>> common-obj-y += socket.o
>> common-obj-y += dump.o
>> common-obj-y += eth.o
>> +common-obj-$(CONFIG_LINUX) += l2tpv3.o
>> common-obj-$(CONFIG_POSIX) += tap.o
>> common-obj-$(CONFIG_LINUX) += tap-linux.o
>> common-obj-$(CONFIG_WIN32) += tap-win32.o
>> diff --git a/net/clients.h b/net/clients.h
>> index 7793294..bbf177c 100644
>> --- a/net/clients.h
>> +++ b/net/clients.h
>> @@ -47,6 +47,8 @@ int net_init_tap(const NetClientOptions *opts, const char
>> *name,
>> int net_init_bridge(const NetClientOptions *opts, const char *name,
>> NetClientState *peer);
>>
>> +int net_init_l2tpv3(const NetClientOptions *opts, const char *name,
>> + NetClientState *peer);
>> #ifdef CONFIG_VDE
>> int net_init_vde(const NetClientOptions *opts, const char *name,
>> NetClientState *peer);
>> diff --git a/net/l2tpv3.c b/net/l2tpv3.c
>> new file mode 100644
>> index 0000000..4439ab7
>> --- /dev/null
>> +++ b/net/l2tpv3.c
>> @@ -0,0 +1,745 @@
>> +/*
>> + * QEMU System Emulator
>> + *
>> + * Copyright (c) 2003-2008 Fabrice Bellard
>> + * Copyright (c) 2012-2014 Cisco Systems
>> + *
>> + * Permission is hereby granted, free of charge, to any person obtaining a
>> copy
>> + * of this software and associated documentation files (the "Software"), to
>> deal
>> + * in the Software without restriction, including without limitation the
>> rights
>> + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
>> + * copies of the Software, and to permit persons to whom the Software is
>> + * furnished to do so, subject to the following conditions:
>> + *
>> + * The above copyright notice and this permission notice shall be included
>> in
>> + * all copies or substantial portions of the Software.
>> + *
>> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
>> OR
>> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
>> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
>> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
>> OTHER
>> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
>> FROM,
>> + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
>> + * THE SOFTWARE.
>> + */
>> +
>> +#include <linux/ip.h>
>> +#include <netdb.h>
>> +#include "config-host.h"
>> +#include "net/net.h"
>> +#include "clients.h"
>> +#include "monitor/monitor.h"
>> +#include "qemu-common.h"
>> +#include "qemu/error-report.h"
>> +#include "qemu/option.h"
>> +#include "qemu/sockets.h"
>> +#include "qemu/iov.h"
>> +#include "qemu/main-loop.h"
>> +
>> +
>> +/* The buffer size needs to be investigated for optimum numbers and
>> + * optimum means of paging in on different systems. This size is
>> + * chosen to be sufficient to accommodate one packet with some headers
>> + */
>> +
>> +#define BUFFER_ALIGN sysconf(_SC_PAGESIZE)
>> +#define BUFFER_SIZE 2048
>> +#define IOVSIZE 2
>> +#define MAX_L2TPV3_MSGCNT 64
>> +#define MAX_L2TPV3_IOVCNT (MAX_L2TPV3_MSGCNT * IOVSIZE)
>> +
>> +/* Header set to 0x30000 signifies a data packet */
>> +
>> +#define L2TPV3_DATA_PACKET 0x30000
>> +
>> +/* IANA-assigned IP protocol ID for L2TPv3 */
>> +
>> +#ifndef IPPROTO_L2TP
>> +#define IPPROTO_L2TP 0x73
>> +#endif
>> +
>> +typedef struct NetL2TPV3State {
>> + NetClientState nc;
>> + int fd;
>> +
>> + /*
>> + * these are used for xmit - that happens packet a time
>> + * and for first sign of life packet (easier to parse that once)
>> + */
>> +
>> + uint8_t *header_buf;
>> + struct iovec *vec;
>> +
>> + /*
>> + * these are used for receive - try to "eat" up to 32 packets at a time
>> + */
>> +
>> + struct mmsghdr *msgvec;
>> +
>> + /*
>> + * peer address
>> + */
>> +
>> + struct sockaddr_storage *dgram_dst;
>> + uint32_t dst_size;
>> +
>> + /*
>> + * L2TPv3 parameters
>> + */
>> +
>> + uint64_t rx_cookie;
>> + uint64_t tx_cookie;
>> + uint32_t rx_session;
>> + uint32_t tx_session;
>> + uint32_t header_size;
>> + uint32_t counter;
>> +
>> + /*
>> + * DOS avoidance in error handling
>> + */
>> +
>> + bool header_mismatch;
>> +
>> + /*
>> + * Ring buffer handling
>> + */
>> +
>> + int queue_head;
>> + int queue_tail;
>> + int queue_depth;
>> +
>> + /*
>> + * Precomputed offsets
>> + */
>> +
>> + uint32_t offset;
>> + uint32_t cookie_offset;
>> + uint32_t counter_offset;
>> + uint32_t session_offset;
>> +
>> + /* Poll Control */
>> +
>> + bool read_poll;
>> + bool write_poll;
>> +
>> + /* Flags */
>> +
>> + bool ipv6;
>> + bool udp;
>> + bool has_counter;
>> + bool pin_counter;
>> + bool cookie;
>> + bool cookie_is_64;
>> +
>> +} NetL2TPV3State;
>> +
>> +static int l2tpv3_can_send(void *opaque);
>> +static void net_l2tpv3_send(void *opaque);
>> +static void l2tpv3_writable(void *opaque);
>> +
>> +static void l2tpv3_update_fd_handler(NetL2TPV3State *s)
>> +{
>> + qemu_set_fd_handler2(s->fd,
>> + s->read_poll ? l2tpv3_can_send : NULL,
>> + s->read_poll ? net_l2tpv3_send : NULL,
>> + s->write_poll ? l2tpv3_writable : NULL,
>> + s);
>> +}
>> +
>> +static void l2tpv3_read_poll(NetL2TPV3State *s, bool enable)
>> +{
>> + if (s->read_poll != enable) {
>> + s->read_poll = enable;
>> + l2tpv3_update_fd_handler(s);
>> + }
>> +}
>> +
>> +static void l2tpv3_write_poll(NetL2TPV3State *s, bool enable)
>> +{
>> + if (s->write_poll != enable) {
>> + s->write_poll = enable;
>> + l2tpv3_update_fd_handler(s);
>> + }
>> +}
>> +
>> +static void l2tpv3_writable(void *opaque)
>> +{
>> + NetL2TPV3State *s = opaque;
>> + l2tpv3_write_poll(s, false);
>> + qemu_flush_queued_packets(&s->nc);
>> +}
>> +
>> +static int l2tpv3_can_send(void *opaque)
>> +{
>> + NetL2TPV3State *s = opaque;
>> +
>> + return qemu_can_send_packet(&s->nc);
>> +}
>> +
>> +static void l2tpv3_send_completed(NetClientState *nc, ssize_t len)
>> +{
>> + NetL2TPV3State *s = DO_UPCAST(NetL2TPV3State, nc, nc);
>> + l2tpv3_read_poll(s, true);
>> +}
>> +
>> +static void l2tpv3_poll(NetClientState *nc, bool enable)
>> +{
>> + NetL2TPV3State *s = DO_UPCAST(NetL2TPV3State, nc, nc);
>> + l2tpv3_write_poll(s, enable);
>> + l2tpv3_read_poll(s, enable);
>> +}
>> +
>> +static void l2tpv3_form_header(NetL2TPV3State *s)
>> +{
>> + uint32_t *counter;
>> +
>> + if (s->udp) {
>> + stl_be_p((uint32_t *) s->header_buf, L2TPV3_DATA_PACKET);
>> + }
>> + stl_be_p(
>> + (uint32_t *) (s->header_buf + s->session_offset),
>> + s->tx_session
>> + );
>> + if (s->cookie) {
>> + if (s->cookie_is_64) {
>> + stq_be_p(
>> + (uint64_t *)(s->header_buf + s->cookie_offset),
>> + s->tx_cookie
>> + );
>> + } else {
>> + stl_be_p(
>> + (uint32_t *) (s->header_buf + s->cookie_offset),
>> + s->tx_cookie
>> + );
>> + }
>> + }
>> + if (s->has_counter) {
>> + counter = (uint32_t *)(s->header_buf + s->counter_offset);
>> + if (s->pin_counter) {
>> + *counter = 0;
>> + } else {
>> + stl_be_p(counter, ++s->counter);
>> + }
>> + }
>> +}
>> +
>> +static ssize_t net_l2tpv3_receive_dgram_iov(NetClientState *nc,
>> + const struct iovec *iov,
>> + int iovcnt)
>> +{
>> + NetL2TPV3State *s = DO_UPCAST(NetL2TPV3State, nc, nc);
>> +
>> + struct msghdr message;
>> + int ret;
>> +
>> + if (iovcnt > MAX_L2TPV3_IOVCNT - 1) {
>> + error_report(
>> + "iovec too long %d > %d, change l2tpv3.h",
>> + iovcnt, MAX_L2TPV3_IOVCNT
>> + );
>> + return -1;
>> + }
>> + l2tpv3_form_header(s);
>> + memcpy(s->vec + 1, iov, iovcnt * sizeof(struct iovec));
>> + s->vec->iov_base = s->header_buf;
>> + s->vec->iov_len = s->offset;
>> + message.msg_name = s->dgram_dst;
>> + message.msg_namelen = s->dst_size;
>> + message.msg_iov = s->vec;
>> + message.msg_iovlen = iovcnt + 1;
>> + message.msg_control = NULL;
>> + message.msg_controllen = 0;
>> + message.msg_flags = 0;
>> + do {
>> + ret = sendmsg(s->fd, &message, 0);
>> + } while ((ret == -1) && (errno == EINTR));
>> + if (ret > 0) {
>> + ret -= s->offset;
>> + } else if (ret == 0) {
>> + /* belt and braces - should not occur on DGRAM
>> + * we should get an error and never a 0 send
>> + */
>> + ret = iov_size(iov, iovcnt);
>> + } else {
>> + /* signal upper layer that socket buffer is full */
>> + ret = -errno;
>> + if (ret == -EAGAIN || ret == -ENOBUFS) {
>> + l2tpv3_write_poll(s, true);
>> + ret = 0;
>> + }
>> + }
>> + return ret;
>> +}
>> +
>> +static ssize_t net_l2tpv3_receive_dgram(NetClientState *nc,
>> + const uint8_t *buf,
>> + size_t size)
>> +{
>> + NetL2TPV3State *s = DO_UPCAST(NetL2TPV3State, nc, nc);
>> +
>> + struct iovec *vec;
>> + struct msghdr message;
>> + ssize_t ret = 0;
>> +
>> + l2tpv3_form_header(s);
>> + vec = s->vec;
>> + vec->iov_base = s->header_buf;
>> + vec->iov_len = s->offset;
>> + vec++;
>> + vec->iov_base = (void *) buf;
>> + vec->iov_len = size;
>> + message.msg_name = s->dgram_dst;
>> + message.msg_namelen = s->dst_size;
>> + message.msg_iov = s->vec;
>> + message.msg_iovlen = 2;
>> + message.msg_control = NULL;
>> + message.msg_controllen = 0;
>> + message.msg_flags = 0;
>> + do {
>> + ret = sendmsg(s->fd, &message, 0);
>> + } while ((ret == -1) && (errno == EINTR));
>> + if (ret > 0) {
>> + ret -= s->offset;
>> + } else if (ret == 0) {
>> + /* belt and braces - should not occur on DGRAM
>> + * we should get an error and never a 0 send
>> + */
>> + ret = size;
>> + } else {
>> + ret = -errno;
>> + if (ret == -EAGAIN || ret == -ENOBUFS) {
>> + /* signal upper layer that socket buffer is full */
>> + l2tpv3_write_poll(s, true);
>> + ret = 0;
>> + }
>> + }
>> + return ret;
>> +}
>> +
>> +static int l2tpv3_verify_header(NetL2TPV3State *s, uint8_t *buf)
>> +{
>> +
>> + uint32_t *session;
>> + uint64_t cookie;
>> +
>> + if ((!s->udp) && (!s->ipv6)) {
>> + buf += sizeof(struct iphdr) /* fix for ipv4 raw */;
>> + }
>> +
>> + /* we do not do a strict check for "data" packets as per
>> + * the RFC spec because the pure IP spec does not have
>> + * that anyway.
>> + */
>> +
>> + if (s->cookie) {
>> + if (s->cookie_is_64) {
>> + cookie = ldq_be_p(buf + s->cookie_offset);
>> + } else {
>> + cookie = ldl_be_p(buf + s->cookie_offset);
>> + }
>> + if (cookie != s->rx_cookie) {
>> + if (!s->header_mismatch) {
>> + error_report("unknown cookie id");
>> + }
>> + return -1;
>> + }
>> + }
>> + session = (uint32_t *) (buf + s->session_offset);
>> + if (ldl_be_p(session) != s->rx_session) {
>> + if (!s->header_mismatch) {
>> + error_report("session mismatch");
>> + }
>> + return -1;
>> + }
>> + return 0;
>> +}
>> +
>> +static void net_l2tpv3_process_queue(NetL2TPV3State *s)
>> +{
>> + int size = 0;
>> + struct iovec *vec;
>> + bool bad_read;
>> + int data_size;
>> + struct mmsghdr *msgvec;
>> +
>> + /* go into ring mode only if there is a "pending" tail */
>> + if (s->queue_depth > 0) {
>> + do {
>> + msgvec = s->msgvec + s->queue_tail;
>> + if (msgvec->msg_len > 0) {
>> + data_size = msgvec->msg_len - s->header_size;
>> + vec = msgvec->msg_hdr.msg_iov;
>> + if ((data_size > 0) &&
>> + (l2tpv3_verify_header(s, vec->iov_base) == 0)) {
>> + vec++;
>> + /* Use the legacy delivery for now, we will
>> + * switch to using our own ring as a queueing mechanism
>> + * at a later date
>> + */
>> + size = qemu_send_packet_async(
>> + &s->nc,
>> + vec->iov_base,
>> + data_size,
>> + l2tpv3_send_completed
>> + );
>> + bad_read = false;
>> + } else {
>> + bad_read = true;
>> + if (!s->header_mismatch) {
>> + /* report error only once */
>> + error_report("l2tpv3 header verification failed");
>> + s->header_mismatch = true;
>> + }
>> + }
>> + } else {
>> + bad_read = true;
>> + }
>> + if ((bad_read) || (size > 0)) {
>> + s->queue_tail = (s->queue_tail + 1) % MAX_L2TPV3_MSGCNT;
>> + s->queue_depth--;
>> + }
>> + } while (
>> + (s->queue_depth > 0) &&
>> + qemu_can_send_packet(&s->nc) &&
>> + ((size > 0) || bad_read)
>> + );
>> + }
>> +}
>> +
>> +static void net_l2tpv3_send(void *opaque)
>> +{
>> + NetL2TPV3State *s = opaque;
>> + int target_count, count;
>> + struct mmsghdr *msgvec;
>> +
>> + /* go into ring mode only if there is a "pending" tail */
>> +
>> + if (s->queue_depth) {
>> +
>> + /* The ring buffer we use has variable intake
>> + * count of how much we can read varies - adjust accordingly
>> + */
>> +
>> + target_count = MAX_L2TPV3_MSGCNT - s->queue_depth;
>> +
>> + /* Ensure we do not overrun the ring when we have
>> + * a lot of enqueued packets
>> + */
>> +
>> + if (s->queue_head + target_count > MAX_L2TPV3_MSGCNT) {
>> + target_count = MAX_L2TPV3_MSGCNT - s->queue_head;
>> + }
>> + } else {
>> +
>> + /* we do not have any pending packets - we can use
>> + * the whole message vector linearly instead of using
>> + * it as a ring
>> + */
>> +
>> + s->queue_head = 0;
>> + s->queue_tail = 0;
>> + target_count = MAX_L2TPV3_MSGCNT;
>> + }
>> +
>> + msgvec = s->msgvec + s->queue_head;
>> + if (target_count > 0) {
>> + do {
>> + count = recvmmsg(
>> + s->fd,
>> + msgvec,
>> + target_count, MSG_DONTWAIT, NULL);
>> + } while ((count == -1) && (errno == EINTR));
>> + if (count < 0) {
>> + /* Recv error - we still need to flush packets here,
>> + * (re)set queue head to current position
>> + */
>> + count = 0;
>> + }
>> + s->queue_head = (s->queue_head + count) % MAX_L2TPV3_MSGCNT;
>> + s->queue_depth += count;
>> + }
>> + net_l2tpv3_process_queue(s);
>> +}
>> +
>> +static void destroy_vector(struct mmsghdr *msgvec, int count, int iovcount)
>> +{
>> + int i, j;
>> + struct iovec *iov;
>> + struct mmsghdr *cleanup = msgvec;
>> + if (cleanup) {
>> + for (i = 0; i < count; i++) {
>> + if (cleanup->msg_hdr.msg_iov) {
>> + iov = cleanup->msg_hdr.msg_iov;
>> + for (j = 0; j < iovcount; j++) {
>> + g_free(iov->iov_base);
>> + iov++;
>> + }
>> + g_free(cleanup->msg_hdr.msg_iov);
>> + }
>> + cleanup++;
>> + }
>> + g_free(msgvec);
>> + }
>> +}
>> +
>> +static struct mmsghdr *build_l2tpv3_vector(NetL2TPV3State *s, int count)
>> +{
>> + int i;
>> + struct iovec *iov;
>> + struct mmsghdr *msgvec, *result;
>> +
>> + msgvec = g_malloc(sizeof(struct mmsghdr) * count);
>> + result = msgvec;
>> + for (i = 0; i < count ; i++) {
>> + msgvec->msg_hdr.msg_name = NULL;
>> + msgvec->msg_hdr.msg_namelen = 0;
>> + iov = g_malloc(sizeof(struct iovec) * IOVSIZE);
>> + msgvec->msg_hdr.msg_iov = iov;
>> + iov->iov_base = g_malloc(s->header_size);
>> + iov->iov_len = s->header_size;
>> + iov++ ;
>> + iov->iov_base = qemu_memalign(BUFFER_ALIGN, BUFFER_SIZE);
>> + iov->iov_len = BUFFER_SIZE;
>> + msgvec->msg_hdr.msg_iovlen = 2;
>> + msgvec->msg_hdr.msg_control = NULL;
>> + msgvec->msg_hdr.msg_controllen = 0;
>> + msgvec->msg_hdr.msg_flags = 0;
>> + msgvec++;
>> + }
>> + return result;
>> +}
>> +
>> +static void net_l2tpv3_cleanup(NetClientState *nc)
>> +{
>> + NetL2TPV3State *s = DO_UPCAST(NetL2TPV3State, nc, nc);
>> + qemu_purge_queued_packets(nc);
>> + l2tpv3_read_poll(s, false);
>> + l2tpv3_write_poll(s, false);
>> + close(s->fd);
>> + destroy_vector(s->msgvec, MAX_L2TPV3_MSGCNT, IOVSIZE);
>> + g_free(s->header_buf);
>> + g_free(s->dgram_dst);
>> +}
>> +
>> +static NetClientInfo net_l2tpv3_info = {
>> + .type = NET_CLIENT_OPTIONS_KIND_L2TPV3,
>> + .size = sizeof(NetL2TPV3State),
>> + .receive = net_l2tpv3_receive_dgram,
>> + .receive_iov = net_l2tpv3_receive_dgram_iov,
>> + .poll = l2tpv3_poll,
>> + .cleanup = net_l2tpv3_cleanup,
>> +};
>> +
>> +int net_init_l2tpv3(const NetClientOptions *opts,
>> + const char *name,
>> + NetClientState *peer)
>> +{
>> +
>> +
>> + const NetdevL2TPv3Options *l2tpv3;
>> + NetL2TPV3State *s;
>> + NetClientState *nc;
>> + int fd = -1, gairet;
>> + struct addrinfo hints;
>> + struct addrinfo *result = NULL;
>> + char *srcport, *dstport;
>> +
>> + nc = qemu_new_net_client(&net_l2tpv3_info, peer, "l2tpv3", name);
>> +
>> + s = DO_UPCAST(NetL2TPV3State, nc, nc);
>> +
>> + s->queue_head = 0;
>> + s->queue_tail = 0;
>> + s->header_mismatch = false;
>> +
>> + assert(opts->kind == NET_CLIENT_OPTIONS_KIND_L2TPV3);
>> + l2tpv3 = opts->l2tpv3;
>> +
>> + if (l2tpv3->has_ipv6 && l2tpv3->ipv6) {
>> + s->ipv6 = l2tpv3->ipv6;
>> + } else {
>> + s->ipv6 = false;
>> + }
>> +
>> + if (l2tpv3->has_rxcookie || l2tpv3->has_txcookie) {
>> + if (l2tpv3->has_rxcookie && l2tpv3->has_txcookie) {
>> + s->cookie = true;
>> + } else {
>> + goto outerr;
>> + }
>> + } else {
>> + s->cookie = false;
>> + }
>> +
>> + if (l2tpv3->has_cookie64 || l2tpv3->cookie64) {
>> + s->cookie_is_64 = true;
>> + } else {
>> + s->cookie_is_64 = false;
>> + }
>> +
>> + if (l2tpv3->has_udp && l2tpv3->udp) {
>> + s->udp = true;
>> + if (!(l2tpv3->has_srcport && l2tpv3->has_dstport)) {
>> + error_report("l2tpv3_open : need both src and dst port for
>> udp");
>> + goto outerr;
>> + } else {
>> + srcport = l2tpv3->srcport;
>> + dstport = l2tpv3->dstport;
>> + }
>> + } else {
>> + s->udp = false;
>> + srcport = NULL;
>> + dstport = NULL;
>> + }
>> +
>> +
>> + s->offset = 4;
>> + s->session_offset = 0;
>> + s->cookie_offset = 4;
>> + s->counter_offset = 4;
>> +
>> + s->tx_session = l2tpv3->txsession;
>> + if (l2tpv3->has_rxsession) {
>> + s->rx_session = l2tpv3->rxsession;
>> + } else {
>> + s->rx_session = s->tx_session;
>> + }
>> +
>> + if (s->cookie) {
>> + s->rx_cookie = l2tpv3->rxcookie;
>> + s->tx_cookie = l2tpv3->txcookie;
>> + if (s->cookie_is_64 == true) {
>> + /* 64 bit cookie */
>> + s->offset += 8;
>> + s->counter_offset += 8;
>> + } else {
>> + /* 32 bit cookie */
>> + s->offset += 4;
>> + s->counter_offset += 4;
>> + }
>> + }
>> +
>> + memset(&hints, 0, sizeof(hints));
>> +
>> + if (s->ipv6) {
>> + hints.ai_family = AF_INET6;
>> + } else {
>> + hints.ai_family = AF_INET;
>> + }
>> + if (s->udp) {
>> + hints.ai_socktype = SOCK_DGRAM;
>> + hints.ai_protocol = 0;
>> + s->offset += 4;
>> + s->counter_offset += 4;
>> + s->session_offset += 4;
>> + s->cookie_offset += 4;
>> + } else {
>> + hints.ai_socktype = SOCK_RAW;
>> + hints.ai_protocol = IPPROTO_L2TP;
>> + }
>> +
>> + gairet = getaddrinfo(l2tpv3->src, srcport, &hints, &result);
>> +
>> + if ((gairet != 0) || (result == NULL)) {
>> + error_report(
>> + "l2tpv3_open : could not resolve src, errno = %s",
>> + gai_strerror(gairet)
>> + );
>> + goto outerr;
>> + }
>> + fd = socket(result->ai_family, result->ai_socktype,
>> result->ai_protocol);
>> + if (fd == -1) {
>> + fd = -errno;
>> + error_report("l2tpv3_open : socket creation failed, errno = %d",
>> -fd);
>> + freeaddrinfo(result);
>> + goto outerr;
>> + }
>> + if (bind(fd, (struct sockaddr *) result->ai_addr, result->ai_addrlen)) {
>> + error_report("l2tpv3_open : could not bind socket err=%i", errno);
>> + goto outerr;
>> + }
>> +
>> + freeaddrinfo(result);
>> +
>> + memset(&hints, 0, sizeof(hints));
>> +
>> + if (s->ipv6) {
>> + hints.ai_family = AF_INET6;
>> + } else {
>> + hints.ai_family = AF_INET;
>> + }
>> + if (s->udp) {
>> + hints.ai_socktype = SOCK_DGRAM;
>> + hints.ai_protocol = 0;
>> + } else {
>> + hints.ai_socktype = SOCK_RAW;
>> + hints.ai_protocol = IPPROTO_L2TP;
>> + }
>> +
>> + gairet = getaddrinfo(l2tpv3->dst, dstport, &hints, &result);
>> + if ((gairet != 0) || (result == NULL)) {
>> + error_report(
>> + "l2tpv3_open : could not resolve dst, error = %s",
>> + gai_strerror(gairet)
>> + );
>> + goto outerr;
>> + }
>> +
>> + s->dgram_dst = g_malloc(sizeof(struct sockaddr_storage));
>> + memset(s->dgram_dst, '\0' , sizeof(struct sockaddr_storage));
>> + memcpy(s->dgram_dst, result->ai_addr, result->ai_addrlen);
>> + s->dst_size = result->ai_addrlen;
>> +
>> + freeaddrinfo(result);
>> +
>> + if (l2tpv3->has_counter && l2tpv3->counter) {
>> + s->has_counter = true;
>> + s->offset += 4;
>> + } else {
>> + s->has_counter = false;
>> + }
>> +
>> + if (l2tpv3->has_pincounter && l2tpv3->pincounter) {
>> + s->has_counter = true; /* pin counter implies that there is
>> counter */
>> + s->pin_counter = true;
>> + } else {
>> + s->pin_counter = false;
>> + }
>> +
>> + if (l2tpv3->has_offset) {
>> + /* extra offset */
>> + s->offset += l2tpv3->offset;
>> + }
>> +
>> + if ((s->ipv6) || (s->udp)) {
>> + s->header_size = s->offset;
>> + } else {
>> + s->header_size = s->offset + sizeof(struct iphdr);
>> + }
>> +
>> + s->msgvec = build_l2tpv3_vector(s, MAX_L2TPV3_MSGCNT);
>> + s->vec = g_malloc(sizeof(struct iovec) * MAX_L2TPV3_IOVCNT);
>> + s->header_buf = g_malloc(s->header_size);
>> +
>> + qemu_set_nonblock(fd);
>> +
>> + s->fd = fd;
>> + s->counter = 0;
>> +
>> + l2tpv3_read_poll(s, true);
>> +
>> + if (!s) {
>> + error_report("l2tpv3_open : failed to set fd handler");
>> + goto outerr;
>> + }
>> + snprintf(s->nc.info_str, sizeof(s->nc.info_str),
>> + "l2tpv3: connected");
>> + return 0;
>> +outerr:
>> + qemu_del_net_client(nc);
>> + if (fd > 0) {
>> + close(fd);
>> + }
>> + return -1;
>> +}
>> +
>> diff --git a/net/net.c b/net/net.c
>> index 0a88e68..749d34c 100644
>> --- a/net/net.c
>> +++ b/net/net.c
>> @@ -731,6 +731,9 @@ static int (* const
>> net_client_init_fun[NET_CLIENT_OPTIONS_KIND_MAX])(
>> [NET_CLIENT_OPTIONS_KIND_BRIDGE] = net_init_bridge,
>> #endif
>> [NET_CLIENT_OPTIONS_KIND_HUBPORT] = net_init_hubport,
>> +#ifdef CONFIG_LINUX
>> + [NET_CLIENT_OPTIONS_KIND_L2TPV3] = net_init_l2tpv3,
>> +#endif
>> };
>>
>>
>> diff --git a/qapi-schema.json b/qapi-schema.json
>> index 83fa485..aefc478 100644
>> --- a/qapi-schema.json
>> +++ b/qapi-schema.json
>> @@ -2941,6 +2941,62 @@
>> '*udp': 'str' } }
>>
>> ##
>> +# @NetdevL2TPv3Options
>> +#
>> +# Connect the VLAN to Ethernet over L2TPv3 Static tunnel
>> +#
>> +# @src: source address
>> +#
>> +# @dst: destination address
>> +#
>> +# @srcport: #optional source port - mandatory for udp, optional for ip
>> +#
>> +# @dstport: #optional destination port - mandatory for udp, optional for ip
>> +#
>> +# @ipv6: #optional - force the use of ipv6
>> +#
>> +# @udp: #optional - use the udp version of l2tpv3 encapsulation
>> +#
>> +# @cookie64: #optional - use 64 bit coookies
>> +#
>> +# @counter: #optional have sequence counter
>> +#
>> +# @pincounter: #optional pin sequence counter to zero -
>> +# workaround for buggy implementations or
>> +# networks with packet reorder
>> +#
>> +# @txcookie: #optional 32 or 64 bit transmit cookie
>> +#
>> +# @rxcookie: #optional 32 or 64 bit receive cookie
>> +#
>> +# @txsession: 32 bit transmit session
>> +#
>> +# @rxsession: #optional 32 bit receive session - if not specified
>> +# set to the same value as transmit
>> +#
>> +# @offset: #optional additional offset - allows the insertion of
>> +# additional application-specific data before the packet payload
>> +#
>> +# Since 2.1
>> +##
>> +{ 'type': 'NetdevL2TPv3Options',
>> + 'data': {
>> + 'src': 'str',
>> + 'dst': 'str',
>> + '*srcport': 'str',
>> + '*dstport': 'str',
>> + '*ipv6': 'bool',
>> + '*udp': 'bool',
>> + '*cookie64': 'bool',
>> + '*counter': 'bool',
>> + '*pincounter': 'bool',
>> + '*txcookie': 'uint64',
>> + '*rxcookie': 'uint64',
>> + 'txsession': 'uint32',
>> + '*rxsession': 'uint32',
>> + '*offset': 'uint32' } }
>> +
>> +##
>> # @NetdevVdeOptions
>> #
>> # Connect the VLAN to a vde switch running on the host.
>> @@ -3014,6 +3070,9 @@
>> # A discriminated record of network device traits.
>> #
>> # Since 1.2
>> +#
>> +# 'l2tpv3' - since 2.1
>> +#
>> ##
>> { 'union': 'NetClientOptions',
>> 'data': {
>> @@ -3021,6 +3080,7 @@
>> 'nic': 'NetLegacyNicOptions',
>> 'user': 'NetdevUserOptions',
>> 'tap': 'NetdevTapOptions',
>> + 'l2tpv3': 'NetdevL2TPv3Options',
>> 'socket': 'NetdevSocketOptions',
>> 'vde': 'NetdevVdeOptions',
>> 'dump': 'NetdevDumpOptions',
>> diff --git a/qemu-options.hx b/qemu-options.hx
>> index 8b94264..e1caf6f 100644
>> --- a/qemu-options.hx
>> +++ b/qemu-options.hx
>> @@ -1395,6 +1395,29 @@ DEF("net", HAS_ARG, QEMU_OPTION_net,
>> " (default=" DEFAULT_BRIDGE_INTERFACE ") using the
>> program 'helper'\n"
>> " (default=" DEFAULT_BRIDGE_HELPER ")\n"
>> #endif
>> +#ifdef __linux__
>> + "-net
>> l2tpv3[,vlan=n][,name=str],src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport],txsession=txsession[,rxsession=rxsession][,ipv6=on/off][,udp=on/off][,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie][,rxcookie=rxcookie][,offset=offset]\n"
>> + " connect the VLAN to an Ethernet over L2TPv3
>> pseudowire\n"
>> + " Linux kernel 3.3+ as well as most routers can talk\n"
>> + " L2TPv3. This transport allows to connect a VM to a
>> VM,\n"
>> + " VM to a router and even VM to Host. It is a
>> nearly-universal\n"
>> + " standard (RFC3391). Note - this implementation uses
>> static\n"
>> + " pre-configured tunnels (same as the Linux kernel).\n"
>> + " use 'src=' to specify source address\n"
>> + " use 'dst=' to specify destination address\n"
>> + " use 'udp=on' to specify udp encapsulation\n"
>> + " use 'dstport=' to specify destination udp port\n"
>> + " use 'dstport=' to specify destination udp port\n"
>> + " use 'ipv6=on' to force v6\n"
>> + " L2TPv3 uses cookies to prevent misconfiguration as\n"
>> + " well as a weak security measure\n"
>> + " use 'rxcookie=0x012345678' to specify a rxcookie\n"
>> + " use 'txcookie=0x012345678' to specify a txcookie\n"
>> + " use 'cookie64=on' to set cookie size to 64 bit,
>> otherwise 32\n"
>> + " use 'counter=off' to force a 'cut-down' L2TPv3 with no
>> counter\n"
>> + " use 'pincounter=on' to work around broken counter
>> handling in peer\n"
>> + " use 'offset=X' to add an extra offset between header
>> and data\n"
>> +#endif
>> "-net
>> socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"
>> " connect the vlan 'n' to another VLAN using a socket
>> connection\n"
>> "-net
>> socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
>> @@ -1730,6 +1753,65 @@ qemu-system-i386 linux.img \
>> -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
>> @end example
>>
>> address@hidden -netdev
>> l2tpv3,address@hidden,address@hidden,address@hidden,address@hidden,address@hidden,address@hidden,address@hidden,ipv6][,udp][,cookie64][,counter][,pincounter][,address@hidden,address@hidden,address@hidden
>> address@hidden -net
>> l2tpv3[,address@hidden,address@hidden,address@hidden,address@hidden,address@hidden,address@hidden,address@hidden,address@hidden,ipv6][,udp][,cookie64][,counter][,pincounter][,address@hidden,address@hidden,address@hidden
>> +Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular
>> +protocol to transport Ethernet (and other Layer 2) data frames between
>> +two systems. It is present in routers, firewalls and the Linux kernel
>> +(from version 3.3 onwards).
>> +
>> +This transport allows a VM to communicate to another VM, router or firewall
>> directly.
>> +
>> address@hidden address@hidden
>> + source address (mandatory)
>> address@hidden address@hidden
>> + destination address (mandatory)
>> address@hidden udp
>> + select udp encapsulation (default is ip).
>> address@hidden address@hidden
>> + source udp port.
>> address@hidden address@hidden
>> + destination udp port.
>> address@hidden ipv6
>> + force v6, otherwise defaults to v4.
>> address@hidden address@hidden
>> address@hidden address@hidden
>> + Cookies are a weak form of security in the l2tpv3 specification.
>> +Their function is mostly to prevent misconfiguration. By default they are 32
>> +bit.
>> address@hidden cookie64
>> + Set cookie size to 64 bit instead of the default 32
>> address@hidden counter=off
>> + Force a 'cut-down' L2TPv3 with no counter as in
>> +draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00
>> address@hidden pincounter=on
>> + Work around broken counter handling in peer. This may also help on
>> +networks which have packet reorder.
>> address@hidden address@hidden
>> + Add an extra offset between header and data
>> +
>> +For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the
>> bridge br-lan
>> +on the remote Linux host 1.2.3.4:
>> address@hidden
>> +# Setup tunnel on linux host using raw ip as encapsulation
>> +# on 1.2.3.4
>> +ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id
>> 1 \
>> + encap udp udp_sport 16384 udp_dport 16384
>> +ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \
>> + 0xFFFFFFFF peer_session_id 0xFFFFFFFF
>> +ifconfig vmtunnel0 mtu 1500
>> +ifconfig vmtunnel0 up
>> +brctl addif br-lan vmtunnel0
>> +
>> +
>> +# on 4.3.2.1
>> +# launch QEMU instance - if your network has reorder or is very lossy add
>> ,pincounter
>> +
>> +qemu-system-i386 linux.img -net nic -net
>> l2tpv3,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter
>> +
>> +
>> address@hidden example
>> +
>> @item -netdev
>> vde,address@hidden,address@hidden,address@hidden,address@hidden,address@hidden
>> @item -net vde[,address@hidden,address@hidden,address@hidden
>> [,address@hidden,address@hidden,address@hidden
>> Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
>> --
>> 1.7.10.4
>>
>>