We are currently facing some migration failure on s390x when running
certain avocado-vt tests, e.g. when running the test
type_specific.io-github-autotest-qemu.migrate.with_reboot.exec.gzip_exec.
This test is using 'migrate -d "exec:nc localhost 5200"' for the migration.
The problem is detected at the receiving side, where the migration stream
apparently ends too early. However, the cause for the problem is at the
sending side: After writing the migration stream into the pipe to netcat,
the source QEMU calls qio_channel_command_close() which closes the pipe
and immediately (!) kills the child process afterwards (via the function
qio_channel_command_abort()). So if the sending netcat did not read the
final bytes from the pipe yet, or if it did not manage to send out all
its buffers yet, it is killed before the whole migration stream is passed
to the destination side.
QEMU can not know how much time is required by the child process to send
over all migration data, so we should not kill it, neither directly nor
after a delay. Let's simply wait for the child process to exit gracefully
instead (this was also the behaviour of pclose() that was used in "exec:"
migration before the QIOChannel rework).
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Add /dev/fdset/ support to QIOChannelFile by calling qemu_open() instead
of open() and qemu_close() instead of close(). There is a subtle
semantic change since qemu_open() automatically sets O_CLOEXEC, but this
doesn't affect any of the users of the function.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
If the file descriptor underlying QIOChannelFile is closed in the
io_close() method, don't close it again in the finalize() method since
the file descriptor number may have been reused in the meantime.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The code wrongly passes the mode to open() only if O_WRONLY is set.
Instead, the mode should be passed when O_CREAT is set (or O_TMPFILE on
Linux). Fix this by always passing the mode since open() will correctly
ignore the mode if it is not needed. Add a testcase which exercises this
bug and also change the existing testcase to check that the mode of the
created file is correct.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
According to the current implementation of websocket protocol in QEMU,
qio_channel_websock_handshake_io tries to read handshake from the
channel to start communication over socket. But this approach
doesn't cover scenario when socket was closed while handshaking.
Therefore, if G_IO_IN is caught and qio_channel_read returns zero,
error has to be set and connection has to be done.
Such behaviour causes 100% CPU load in main QEMU loop, because main loop
poll continues to receive and handle G_IO_IN events from websocket.
Step to reproduce 100% CPU load:
1) start qemu with the simplest configuration
$ qemu -vnc [::1]:1,websocket=7500
2) open any vnc listener (which doesn't follow websocket
protocol)
$ vncviewer :7500
3) kill listener
4) qemu main thread eats 100% CPU
Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhmedov@virtuozzo.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The sources array does not escape out of qio_net_listener_wait_client, so
we have to free it.
Reported by Coverity.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes, with the change
to target/s390x/gen-features.c manually reverted, and blank lines
around deletions collapsed.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-3-armbru@redhat.com>
The existing QIOChannelSocket class provides the ability to
listen on a single socket at a time. This patch introduces
a QIONetListener class that provides a higher level API
concept around listening for network services, allowing
for listening on multiple sockets.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This fixes a compiler warning:
/qemu/io/channel-websock.c:163:5: error:
function might be possible candidate for ‘gnu_printf’ format attribute
[-Werror=suggest-attribute=format]
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Acked-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Coverity pointed out the 'date' is not free()d in the error
path
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The noVNC server sends a header "Connection: keep-alive, Upgrade" which
fails our simple equality test. Split the header on ',', trim whitespace
and then check for 'upgrade' token.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Currently most outbound I/O on the websock channel gets copied into the
rawoutput buffer, and then immediately copied again into the encoutput
buffer, with a header prepended. Now that qio_channel_websock_encode
accepts a struct iovec, we can trivially remove this bounce buffering
and write directly to encoutput.
In doing so, we also now correctly validate the encoutput size against
the QIO_CHANNEL_WEBSOCK_MAX_BUFFER limit.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Instead of requiring use of another Buffer, pass a struct iovec
into qio_channel_websock_encode, which gives callers more
flexibility in how they process data.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The qio_channel_websock_encode method is only used in one place,
everything else calls qio_channel_websock_encode_buffer directly.
It can also be pushed up a level into the qio_channel_websock_writev
method, since every other caller of qio_channel_websock_write_wire
has already filled encoutput.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
We must ensure we don't get flooded with ping replies if the outbound
channel is slow. Currently we do this by keeping the ping reply in a
separate temporary buffer and only writing it if the encoutput buffer
is completely empty. This is overly pessimistic, as it is reasonable
to add a ping reply to the encoutput buffer even if it has previous
data in it, as long as that previous data doesn't include a ping
reply.
To track this better, put the ping reply directly into the encoutput
buffer, and then record the size of encoutput at this time in
pong_remain. As we write encoutput to the underlying channel, we
can decrement the pong_remain counter. Once it hits zero, we can
accept further ping replies for transmission.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The websocket GSource is monitoring the size of the rawoutput
buffer to determine if the channel can accepts more writes.
The rawoutput buffer, however, is merely a temporary staging
buffer before data is copied into the encoutput buffer. Thus
its size will always be zero when the GSource runs.
This flaw causes the encoutput buffer to grow without bound
if the other end of the underlying data channel doesn't
read data being sent. This can be seen with VNC if a client
is on a slow WAN link and the guest OS is sending many screen
updates. A malicious VNC client can act like it is on a slow
link by playing a video in the guest and then reading data
very slowly, causing QEMU host memory to expand arbitrarily.
This issue is assigned CVE-2017-15268, publically reported in
https://bugs.launchpad.net/qemu/+bug/1718964
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
It is useful to trace websockets frame encoding/decoding when debugging
problems.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Make a best effort attempt to close websocket connections according to
the RFC. Sends the close message, as room permits in the socket buffer,
and immediately closes the socket.
Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add an immediate ping reply (pong) to the outgoing stream when a ping
is received. Unsolicited pongs are ignored.
Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Keep pings and gratuitous pongs generated by web browsers from killing
websocket connections.
Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Some browsers send pings/pongs with no payload, so allow empty payloads
instead of closing the connection.
Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Allows fragmented binary frames by saving the previous opcode. Handles
the case where an intermediary (i.e., web proxy) fragments frames
originally sent unfragmented by the client.
Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Gets rid of unnecessary bit shifting and performs proper EOF checking to
avoid a large number of repeated calls to recvmsg() when a client
abruptly terminates a connection (bug fix).
Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When checking the value of the Connection and Upgrade HTTP headers
the websock RFC (6455) requires the comparison to be case insensitive.
The Connection value should be an exact match not a substring.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When the websocket handshake fails it is useful to log the real
error message via the trace points for debugging purposes.
Fixes bug: #1715186
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When any error occurs while processing the websockets handshake,
QEMU just terminates the connection abruptly. This is in violation
of the HTTP specs and does not help the client understand what they
did wrong. This is particularly bad when the client gives the wrong
path, as a "404 Not Found" would be very helpful.
Refactor the handshake code so that it always sends a response to
the client unless there was an I/O error.
Fixes bug: #1715186
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Some callers want to distinguish between clean EOF (no bytes read)
vs. a short read (at least one byte read, but EOF encountered
before reaching the desired length), as it allows clients the
ability to do a graceful shutdown when a server shuts down at
defined safe points in the protocol, rather than treating all
shutdown scenarios as an error due to EOF. However, we don't want
to require all callers to have to check for early EOF. So add
another wrapper function that can be used by the callers that care
about the distinction.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20170905191114.5959-3-eblake@redhat.com>
Acked-by: Daniel P. Berrange <berrange@redhat.com>
The new qio_channel_{read,write}{,v}_all functions are documented
as yielding until data is available. When used on a blocking
channel, this yield is done via qio_channel_wait() which spawns
a nested event loop under the hood (so it is that secondary loop
which yields as needed); but if we are already in a coroutine (at
which point QIO_CHANNEL_ERR_BLOCK is only possible if we are a
non-blocking channel), we want to yield the current coroutine
instead of spawning a nested event loop.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20170905191114.5959-2-eblake@redhat.com>
Acked-by: Daniel P. Berrange <berrange@redhat.com>
[commit message updated]
Signed-off-by: Eric Blake <eblake@redhat.com>
These functions wait until they are able to read / write the full
requested data buffer(s).
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The non-blocking connect mechanism is obsolete, and it doesn't
work well in inet connection, because it will call getaddrinfo
first and getaddrinfo will blocks on DNS lookups. Since commit
e65c67e4 & d984464e, the non-blocking connect of migration goes
through QIOChannel in a different manner(using a thread), and
nobody use this old non-blocking connect anymore.
Any newly written code which needs a non-blocking connect should
use the QIOChannel code, so we can drop NonBlockingConnectHandler
as a concept entirely.
Suggested-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When accept failed, we should setup errp with the reason. More
importantly, the caller may assume errp be non-NULL when error happens,
and not setting the errp may crash QEMU.
At the same time, move the trace_qio_channel_socket_accept_fail() after
the if check on EINTR. Two reasons:
1. when EINTR happened, it's not really a fault (we should just try
again), so we should not log with an "accept failure".
2. trace_*() functions may overwrite errno, then the old errno will be
missing. We need to either check errno before trace_*() calls, or
reserve the errno.
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1501666880-10159-3-git-send-email-peterx@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
With the move of some docs/ to docs/devel/ on ac06724a71,
no references were updated.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
The original InetSocketAddress struct may have has_ipv4 and
has_ipv6 fields set, which will control both the ai_family
used during DNS resolution, and later use of the V6ONLY
flag.
Currently the standalone DNS resolver code drops the
has_ipv4 & has_ipv6 flags after resolving, which means
the later bind() code won't correctly set V6ONLY.
This fixes the following scenarios
-vnc :0,ipv4=off
-vnc :0,ipv6=on
-vnc :::0,ipv4=off
-vnc :::0,ipv6=on
which all mistakenly accepted IPv4 clients
Acked-by: Gerd Hoffmann <kraxel@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Assigning directly to *errp is not valid, as errp may be NULL,
&error_fatal, or &error_abort. Use error_propagate() instead.
Cc: "Daniel P. Berrange" <berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20170608133906.12737-4-ehabkost@redhat.com>
Reviewed-by: Manos Pitsidianakis <el13635@mail.ntua.gr>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
If properly preceded by qio_channel_detach_aio_context, this function really
has nothing to do except setting ioc->ctx.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
SocketAddressLegacy is a simple union, and simple unions are awkward:
they have their variant members wrapped in a "data" object on the
wire, and require additional indirections in C. SocketAddress is the
equivalent flat union. Convert all users of SocketAddressLegacy to
SocketAddress, except for existing external interfaces.
See also commit fce5d53..9445673 and 85a82e8..c5f1ae3.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-7-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Minor editing accident fixed, commit message and a comment tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The next commit will rename SocketAddressFlat to SocketAddress, and
the commit after that will replace most uses of SocketAddressLegacy by
SocketAddress, replacing most of this commit's renames right back.
Note that checkpatch emits a few "line over 80 characters" warnings.
The long lines are all temporary; the SocketAddressLegacy replacement
will shorten them again.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-5-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The qio_dns_resolver_lookup_sync() method is required to be a no-op
for socket kinds that don't require name resolution. Thus the KIND_FD
handling should not return an error.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The channel socket was initialized manually, but forgot to set
QIO_CHANNEL_FEATURE_SHUTDOWN. Thus, the colo_process_incoming_thread
would hang at recvmsg. This patch just call qio_channel_socket_new to
get channel, Which set QIO_CHANNEL_FEATURE_SHUTDOWN already.
Signed-off-by: Wang Guang<wang.guang55@zte.com.cn>
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
We have quite a few switches over SocketAddressKind. Some have case
labels for all enumeration values, others rely on a default label.
Some abort when the value isn't a valid SocketAddressKind, others
report an error then.
Unify as follows. Always provide case labels for all enumeration
values, to clarify intent. Abort when the value isn't a valid
SocketAddressKind, because the program state is messed up then.
Improve a few error messages while there.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1490895797-29094-4-git-send-email-armbru@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
The current websockets protocol handshake code is very relaxed, just
doing crude string searching across the HTTP header data. This causes
it to both reject valid connections and fail to reject invalid
connections. For example, according to the RFC 6455 it:
- MUST reject any method other than "GET"
- MUST reject any HTTP version less than "HTTP/1.1"
- MUST reject Connection header without "Upgrade" listed
- MUST reject Upgrade header which is not 'websocket'
- MUST reject missing Host header
- MUST treat HTTP header names as case insensitive
To do all this validation correctly requires that we fully parse the
HTTP headers, populating a data structure containing the header
fields.
After this change, we also reject any path other than '/'
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The qio_channel_websock_read_wire() method will read upto 4096
bytes off the socket and then decode the websockets header and
payload. The code was only decoding a single websockets frame,
even if the buffered data contained multiple frames. This meant
that decoding of subsequent frames was delayed until further
input arrived on the socket. This backlog of delayed frames
gets worse & worse over time.
Symptom was that when connecting to the VNC server via the
built-in websockets server, mouse/keyboard interaction would
start out fine, but slowly get more & more delayed until it
was unusable.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Support separate coroutines for reading and writing, and place the
read/write handlers on the AioContext that the QIOChannel is registered
with.
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213135235.12274-7-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is in preparation for making qio_channel_yield work on
AioContexts other than the main one.
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213135235.12274-6-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
If a QIOTask has an error set and the calling code uses
qio_task_propagate_error() to steal the reference to
that Error object, the task would not clear its own
reference. This would lead to a double-free when
qio_task_free runs, if the caller had (correctly) freed
the Error object they now owned.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Currently DNS resolution is done automatically as part
of the creation of a QIOChannelSocket object instance.
This works ok for network clients where you just end
up a single network socket, but for servers, the results
of DNS resolution may require creation of multiple
sockets.
Introducing a DNS resolver API allows DNS resolution
to be separated from the socket object creation. This
will make it practical to create multiple QIOChannelSocket
instances for servers.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>