Commit Graph

175 Commits

Author SHA1 Message Date
Michal Privoznik
8b0cb0e666 virNetSocketCheckProtocols: Confirm IPv4 by lookup too
Historically, if we found an interface with an IPv6 address we
did not blindly trust that host is IPv6 capable (as in we can
successfully translate IPv4 addresses) but used getaddrinfo() to
confirm it. Turns out, we have use the same argument for IPv4.
For instance, in an namespace created by the following steps,
getaddrinfo("127.0.0.1", ...) fails (demonstrating by "Socket
TCP/IPv4 Accept" test case failing in virnetsockettest):

  unshare -n
  ip link set lo up
  ip link add dummy0 type dummy
  ip link set dummy0 up

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-07-16 12:19:31 +02:00
Michal Privoznik
9536379da4 virNetSocketCheckProtocols: lookup IPv6 only if suspecting IPv6
There is not much sense trying to disprove host is IPv6 capable
if we know after first round (getifaddrs()) that is is not.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-07-16 12:19:22 +02:00
Michal Privoznik
e146f4beef virNetSocketCheckProtocols: Separate out checking family via getaddrinfo()
The virNetSocketCheckProtocols() function is supposed to tell
caller whether IPv4 and/or IPv6 is supported on the system. In
the initial round, it uses getifaddrs() to see if an interface
has IPv4/IPv6 address assigned and then to double check IPv6 it
uses getaddrinfo() to lookup IPv6 loopback address. Separate out
this latter code because it is going to be reused.

Since the original code lived under an #ifdef and the new
function doesn't it is marked as unused - because on some systems
it may be so.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-07-16 12:19:05 +02:00
Michal Privoznik
e71e13488d Substitute security_context_t with char *
Historically, we've used security_context_t for variables passed
to libselinux APIs. But almost 7 years ago, libselinux developers
admitted in their API that in fact, it's just a 'char *' type
[1]. Ever since then the APIs accept 'char *' instead, but they
kept the old alias just for API stability. Well, not anymore [2].

1: 9eb9c93275
2: 7a124ca275

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
2020-07-15 14:31:07 +02:00
Laine Stump
817519e900 rpc: use g_auto() for all virBuffers
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-07-08 16:34:42 -04:00
Michal Privoznik
ce87e7f2a6 rpc: Make some functions void
There are few functions that currently return an integer but in
fact they always return the same integer (zero). Make them void.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2020-05-05 13:08:48 +02:00
Zhimin Feng
9e85e118ca rpc: getaddrinfo: also accept IPv4-mapped IPv6 addresses
If only IPv6 is configured on the host, getaddrinfo with AI_ADDRCONFIG
in hints would return EAI_ADDRFAMILY for nodenames that resolve to IPv4.

Also pass AI_V4MAPPED to accept IPv4-mapped addresses on IPv6-only
systems.

Signed-off-by: Zhimin Feng <fengzhimin1@huawei.com>
[rewrote the commit message - jtomko]
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2020-03-09 12:37:47 +01:00
Peter Krempa
e9153cc604 util: json: Convert virJSONValueNewObject() to g_new0
Make it obvious that the function always returns a valid pointer and fix
all callers.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2020-03-05 11:31:38 +01:00
Daniel P. Berrangé
2621d48f00 gnulib: delete all gnulib integration
This deletes all trace of gnulib from libvirt. We still
have the keycodemapdb submodule to deal with. The simple
solution taken was to update it when running autogen.sh.

Previously gnulib could auto-trigger refresh when running
'make' too. We could figure out a solution for this, but
with the pending meson rewrite it isn't worth worrying
about, given how infrequently keycodemapdb changes.

Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-02-07 15:03:54 +00:00
Daniel P. Berrangé
cc46e137eb src: convert code to use virPipe APIs
This addreses portability to Windows and standardizes
error reporting. This fixes a number of places which
failed to set O_CLOEXEC or failed to report errors.

Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-02-04 14:00:44 +00:00
Daniel P. Berrangé
bfeb56b3ad src: remove sys/wait.h from many files
Most code now uses the virProcess / virCommand APIs, so
the need for sys/wait.h is quite limited. Removing this
include removes the dependency on GNULIB providing a
dummy sys/wait.h for Windows.

Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-02-04 14:00:44 +00:00
Daniel P. Berrangé
3d63a187ba bootstrap: remove 18 more gnulib modules
* chown: use is conditionally compiled
* configmake: functionality imported to Makefile.am
* getaddrinfo: we have no portability problems
  with Windows impl
* getpass: simplified impl is imported
* mgetgroups: getgrouplist is used directly
* net_if: header includes are conditionalized
* netdb: header includes are conditionalized
* passfd: simplified impl is imported
* posix-shell: functionality was unused & removed
* sigaction: usage is conditionalized
* sigpipe: usage is conditionalized
* stat-time: struct stat is used directly
* strchrnul: usage is eliminated
* strtok_r: usage is not a portability problem
* sys_stat: usage is conditionalized
* uname: rewritten to use native Win32 function to
  get host arch
* waitpid: usage is conditionalized
* wcwidth: rewritten using g_unichar APIs

Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-29 14:51:40 +00:00
Daniel P. Berrangé
e429934550 src: conditionalize EAI_ADDRFAMILY
The EAI_ADDRFAMILY constant has been removed from FreeBSD
headers, supposedly because it is deprecated by new RFC
drafts.

Previously GNULIB was providing a replacement because
MinGW lacked it too. The replacement provided for MinGW
was thus being used on FreeBSD too, but with a completely
bogus integer value.

Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-29 14:51:40 +00:00
Daniel P. Berrangé
fc920f704c src: convert all code to use virsocket.h
There are a large number of different header files that
are related to the sockets APIs. The virsocket.h header
includes all of the relevant headers for Windows and UNIX
in one convenient place. If virsocketaddr.h is already
included, then there's no need for virsocket.h

Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-29 14:51:40 +00:00
Daniel P. Berrangé
4b9919af40 src: conditionalize use of F_DUPFD_CLOEXEC
The F_DUPFD_CLOEXEC functionality is not available on
some platformms. We must thus explicitly call the
virSetCloexec function once we remove GNULIB's equiv
fix for this.

Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-29 14:51:40 +00:00
Daniel P. Berrangé
17460825f3 src: implement APIs for passing FDs over UNIX sockets
This is a simplified variant of gnulib's passfd module
without the portability code that we do not require.

Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-29 14:51:39 +00:00
Pavel Hrdina
153fd68368 src: remove WITH_GNUTLS usage
Since commit <60d9ad6f1e42618fce10baeb0f02c35e5ebd5b24> we require
GnuTLS and since commit <ac0d21c762351f58dd5d2dafa2014ed48a8b49f3>
we can actually drop the usage of WITH_GNUTLS.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-01-22 18:07:09 +01:00
Daniel P. Berrangé
210e19702e src: convert code to use new socket portability wrappers
Convert to use socket wrappers. Aside from the header file
include change, this requires changing close -> closesocket
since our portability isn't trying to replace the close
function.

Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-17 10:01:57 +00:00
Daniel P. Berrangé
12d17dcc26 src: replace last_component() with g_path_get_basename()
The last_component() method is a GNULIB custom function
that returns a pointer to the base name in the path.
This is similar to g_path_get_basename() but without the
malloc. The extra malloc is no trouble for libvirt's
needs so we can use g_path_get_basename().

Reviewed-by: Fabiano Fidêncio <fidencio@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-03 15:42:13 +00:00
Fabiano Fidêncio
b0ffed92f1 rpc: Don't check the output of virGetUserRuntimeDirectory()
virGetUserRuntimeDirectory() *never* *ever* returns NULL, making the
checks for it completely unnecessary.

Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-12-20 09:38:43 +01:00
Pavel Hrdina
caab1fbd67 use g_ascii_isspace instead of c_isspace from gnulib
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
2019-12-10 13:49:24 +01:00
Peter Krempa
1a288c7e8a rpc: use virStringSplit instead of strsep
When parsing allowed authentication methods for the native ssh lib
transports we used strsep. Since we have virStringSplit helper let's use
that one.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-11-14 15:50:43 +01:00
Daniel Henrique Barboza
2d13431d45 rpc: remove unneeded cleanup labels
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-11-12 17:54:01 +01:00
Michal Privoznik
c684b3c7e8 rpc: Use g_strdup_printf() instead of virAsprintf()
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2019-11-12 16:15:58 +01:00
Peter Krempa
0967708b81 util: buffer: Remove virBufferCheckError
The function now does not return an error so we can drop it fully.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-10-24 19:35:34 +02:00
Ján Tomko
45bf10ba1d rpc: use g_strdup instead of VIR_STRDUP
Replace all occurrences of
  if (VIR_STRDUP(a, b) < 0)
     /* effectively dead code */
with:
  a = g_strdup(b);

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-10-21 12:51:58 +02:00
Ján Tomko
8b5ef0a6b8 rpc: use G_GNUC_UNUSED
Use G_GNUC_UNUSED from GLib instead of ATTRIBUTE_UNUSED.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-10-15 11:25:24 +02:00
Daniel P. Berrangé
27cb4c1a53 build: remove use of usleep gnulib module in favour of g_usleep
The usleep function was missing on older mingw versions, but we can rely
on it existing everywhere these days. It may only support times upto 1
second in duration though, so we'll prefer to use g_usleep instead.

The commandhelper program is not changed since that can't link to glib.
Fortunately it doesn't need to build on Windows platforms either.

Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-10-14 10:54:42 +01:00
Daniel P. Berrangé
76d31244c5 rpc: fix escaping of shell path for netcat binary
Consider having a nc binary in the path with a space in its name,
for example '/tmp/fo o/nc'

This results in libvirt running SSH with the following arg value

  "'if ''/tmp/fo o/nc'' -q 2>&1 | grep \"requires
    an argument\" >/dev/null 2>&1; then ARG=-q0;
    else ARG=;fi;''/tmp/fo o/nc'' $ARG -U
    /var/run/libvirt/libvirt-sock'"

The use of the single quote escaping was introduced by

  commit 6ac6238de3
  Author: Guido Günther <agx@sigxcpu.org>
  Date:   Thu Oct 13 21:49:01 2011 +0200

    Use virBufferEscapeShell in virNetSocketNewConnectSSH

    to escape the netcat command since it's passed to the shell. Adjust
    expected test case output accordingly.

While the intention of this change was good, the result is broken as it
is still underquoted.

On the SSH server side, SSH itself runs the command via the shell.
Our command is then invoking the shell again. Thus we see

$ virsh -c qemu+ssh://root@domokun/system?netcat=%2Ftmp%2Ffo%20o%2Fnc list
error: failed to connect to the hypervisor
error: End of file while reading data: sh: /tmp/fo: No such file or directory: Input/output error

With the second level of escaping added we can now successfully use a nc
binary with a space in the path.

The original test case added was misleading as it illustrated using a
binary path of 'nc -4' which is not a path, it is a command with a
separate argument, which is getting interpreted as a path.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-10-01 12:57:07 +01:00
Daniel P. Berrangé
fcf93c3ee0 util: simplify virCommand APIs for env passthrough.
Now that 100% of libvirt code is forbidden in a SUID environment,
we no longer need to worry about whether env variables are
trustworthy or not. The virt-login-shell setuid program, which
does not link to any libvirt code, will purge all environment
variables, except $TERM, before invoking the virt-login-shell-helper
program which uses libvirt.

Thus we only need one API for env passthrough in virCommand.

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-08-07 16:54:02 +01:00
Daniel P. Berrangé
9d7fcdbf83 remote: increase daemon shutdown timer to 2 minutes
Shutting down the daemon after 30 seconds of being idle is a little bit
too aggressive. Especially when using 'virsh' in single-shot mode, as
opposed to interactive shell mode, it would not be unusual to have
more than 30 seconds between commands. This will lead to the daemon
shutting down and starting up between a series of commands.

Increasing the shutdown timer to 2 minutes will make it less likely that
the daemon will shutdown while the user is in the middle of a series of
commands.

Reviewed-by: Jim Fehlig <jfehlig@suse.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-07-19 14:33:47 +01:00
Daniel P. Berrangé
1519c55dc8 rpc: avoid unlinking sockets passed in from systemd
Currently the socket code will unlink any UNIX socket path which is
associated with a server socket. This is not fine grained enough, as we
need to avoid unlinking server sockets we were passed by systemd.

To deal with this we must explicitly track whether each socket needs to
be unlinked when closed, separately of the client vs server state.

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-07-12 16:55:39 +01:00
Daniel P. Berrangé
f8b3905edf rpc: ensure all sockets bind to same port when service is NULL
When the service passed to getaddrinfo is NULL the kernel will choose a
free port to bind to. In a dual stack though we will get separate
sockets for IPv4 and IPv6 and we need them to bind to the same port
number. Thus once the kerel has auto-selected a port for the first
socket, we must disable auto-select for subsequent IP sockets and force
reuse of the first port.

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-07-12 16:55:39 +01:00
Daniel P. Berrangé
1939bcd539 rpc: always pass "-T -e none" args to ssh
Way back in the past, the "no_tty=1" option was added for the remote
driver to disable local password prompting by disabling use of the local
tty:

  commit b32f429849
  Author: Daniel P. Berrange <berrange@redhat.com>
  Date:   Fri Sep 21 20:17:09 2007 +0000

    Added a no_tty param to remote URIs to stop SSH prompting for password

This was done by adding "-T -o BatchMode=yes -e none" args to ssh. This
achieved the desired results but is none the less semantically flawed
because it is mixing up config parameters for the local tty vs the
remote tty.

The "-T" arg stops allocation of a TTY on the remote host. This is good
for all libvirt SSH tunnels as we never require a TTY for our usage
model, so we should have just passed this unconditionally.

The "-e none" option disables the escape character for sessions with a
TTY. If we pass "-T" this is not required, but it also not harmful to
add it, so we should just pass it unconditionally too.

Only the "-o BatchMode=yes" option is related to disabling local
password prompts and thus needs control via the no_tty URI param.

Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-07-11 15:26:54 +01:00
Daniel P. Berrangé
836f4e0659 rpc: add helper API for getting UNIX path from socket object
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-07-11 14:13:03 +01:00
Cole Robinson
af36f8a641 Require a semicolon for VIR_ONCE_GLOBAL_INIT calls
Missing semicolon at the end of macros can confuse some analyzers
(like cppcheck <filename>). VIR_ONCE_GLOBAL_INIT is almost
exclusively called without an ending semicolon, but let's
standardize on using one like the other macros.

Add a dummy struct definition at the end of the macro, so
the compiler will require callers to add a semicolon.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
2019-02-03 17:46:29 -05:00
Daniel P. Berrangé
600462834f Remove all Author(s): lines from source file headers
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.

In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.

With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to  find the
author of a particular bit of code.

This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.

The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.

Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-13 16:08:38 +00:00
Daniel P. Berrangé
2eb748d259 rpc: treat EADDRNOTAVAIL as non-fatal when listening
Consider creating a listener socket from a hostname that resolves to
multiple addresses. It might be the case that the hostname resolves to
both an IPv4 and IPv6 address because it is reachable over both
protocols, but the IPv6 connectivity is provided off-host. In such a
case no local NIC will have IPv6 and so bind() would fail with the
EADDRNOTAVAIL errno. Thus it should be treated as non-fatal as long as
at least one socket was succesfully bound.

Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-07-25 16:55:55 +01:00
Daniel P. Berrangé
f56eb726b1 socket: preserve real errno when socket/bind calls fail
When reporting socket/bind failures we want to ensure any fatal error
reported is as accurate as possible. We'll prefer reporting a bind()
errno over a socket() errno, because if socket() works but bind() fails
that is a more significant event.

Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-07-25 16:55:38 +01:00
Andrea Bolognani
6c0d0210cb src: Make virStr*cpy*() functions return an int
Currently, the functions return a pointer to the
destination buffer on success or NULL on failure.

Not only does this kind of error handling look quite
alien in the context of libvirt, where most functions
return zero on success and a negative int on failure,
but it's also somewhat pointless because unless there's
been a failure the returned pointer will be the same
one passed in by the user, thus offering no additional
value.

Change the functions so that they return an int
instead.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
2018-07-23 14:27:30 +02:00
Martin Kletzander
b63d30d601 rpc/: Remove spaces after casts
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2018-05-03 22:31:37 +02:00
Michal Privoznik
10f94828ea virobject: Introduce VIR_CLASS_NEW() macro
So far we are repeating the following lines over and over:

  if (!(virSomeObjectClass = virClassNew(virClassForObject(),
                             "virSomeObject",
                             sizeof(virSomeObject),
                             virSomeObjectDispose)))
      return -1;

While this works, it is impossible to do some checking. Firstly,
the class name (the 2nd argument) doesn't match the name in the
code in all cases (the 3rd argument). Secondly, the current style
is needlessly verbose. This commit turns example into following:

  if (!(VIR_CLASS_NEW(virSomeObject,
                      virClassForObject)))
      return -1;

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2018-04-18 10:04:55 +02:00
Jim Fehlig
412afdb8f4 util: introduce virSocketAddrParseAny
When preparing for migration, the libxl driver creates a new TCP listen
socket for the incoming migration by calling virNetSocketNewListenTCP,
passing the destination host name. virNetSocketNewListenTCP calls
virSocketAddrParse to check if the host name is a wildcard address, in
which case it avoids adding the AI_ADDRCONFIG flag to the hints passed to
getaddrinfo. If the host name is not an IP address, virSocketAddrParse
reports an error

error : virSocketAddrParseInternal:121 : Cannot parse socket address
'myhost.example.com': Name or service not known

But virNetSocketNewListenTCP succeeds regardless and the overall migration
operation succeeds.

Introduce virSocketAddrParseAny and use it when simply testing if a host
name/addr is parsable.

Signed-off-by: Jim Fehlig <jfehlig@suse.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-04-05 14:50:15 -06:00
Daniel P. Berrange
4e13fb02fe rpc: fix race sending and encoding sasl data
The virNetSocketWriteSASL method has to encode the buffer it is given and then
write it to the underlying socket. This write is not guaranteed to send the
full amount of data that was encoded by SASL. We cache the SASL encoded data so
that on the next invocation of virNetSocketWriteSASL we carry on sending it.

The subtle problem is that the 'len' value passed into virNetSocketWriteSASL on
the 2nd call may be larger than the original value. So when we've completed
sending the SASL encoded data we previously cached, we must return the original
length we encoded, not the new length.

This flaw means we could potentially have been discarded queued data without
sending it. This would have exhibited itself as a libvirt client never receiving
the reply to a method it invokes, async events silently going missing, or worse
stream data silently getting dropped.

For this to be a problem libvirtd would have to be queued data to send to the
client, while at the same time the TCP socket send buffer is full (due to a very
slow client). This is quite unlikely so if this bug was ever triggered by a real
world user it would be almost impossible to reproduce or diagnose, if indeed it
was ever noticed at all.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2018-01-25 16:29:24 +00:00
Daniel P. Berrange
e4cb850081 rpc: avoid ssh interpreting malicious hostname as arguments
Inspired by the recent GIT / Mercurial security flaws
(http://blog.recurity-labs.com/2017-08-10/scm-vulns),
consider someone/something manages to feed libvirt a bogus
URI such as:

  virsh -c qemu+ssh://-oProxyCommand=gnome-calculator/system

In this case, the hosname "-oProxyCommand=gnome-calculator"
will get interpreted as an argument to ssh, not a hostname.
Fortunately, due to the set of args we have following the
hostname, SSH will then interpret our bit of shell script
that runs 'nc' on the remote host as a cipher name, which is
clearly invalid. This makes ssh exit during argv parsing and
so it never tries to run gnome-calculator.

We are lucky this time, but lets be more paranoid, by using
'--' to explicitly tell SSH when it has finished seeing
command line options. This forces it to interpret
"-oProxyCommand=gnome-calculator" as a hostname, and thus
see a fail from hostname lookup.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-08-29 18:02:03 +01:00
Peter Krempa
494c302c7f rpc: socket: Add possibility to suppress errors on read hangup
In some cases a read error due to connection hangup is expected. This
patch adds a flag that removes the logging of a virError in such case.
2017-03-17 17:19:00 +01:00
Pino Toscano
22eaee8e01 remote: expose a new libssh transport
Implement in virtNetClient and VirNetSocket the needed functions to
expose a new libssh transport, providing all the options that the
libssh2 transport supports.
2016-11-15 15:50:51 +01:00
Pino Toscano
0e9fec979d virNetSocket: allow to not close FD
Add an internal variable to mark the FD as "not owned" by the
virNetSocket, in case the internal implementation takes the actual
ownership of the descriptor; this avoids a warning when closing the
socket, as the FD would be invalid.
2016-11-15 15:50:51 +01:00
Ján Tomko
ea537e7b36 Add SASL to virNetSocket{Local,Remote}AddrString
Rename them to virNetSocket{Local,Remote}AddrStringSASL
to make their format more obvious.
2016-06-23 22:23:21 +02:00
Ján Tomko
dbce70b243 virNetSocket: rename AddrStr to AddrStrSASL
Make it more obvious that these are in the SASL format.
2016-06-23 22:23:21 +02:00