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2017-06-15nbd: Fix regression on resiliency to port scanEric Blake1-1/+5
Back in qemu 2.5, qemu-nbd was immune to port probes (a transient server would not quit, regardless of how many probe connections came and went, until a connection actually negotiated). But we broke that in commit ee7d7aa when removing the return value to nbd_client_new(), although that patch also introduced a bug causing an assertion failure on a client that fails negotiation. We then made it worse during refactoring in commit 1a6245a (a segfault before we could even assert); the (masked) assertion was cleaned up in d3780c2 (still in 2.6), and just recently we finally fixed the segfault ("nbd: Fully intialize client in case of failed negotiation"). But that still means that ever since we added TLS support to qemu-nbd, we have been vulnerable to an ill-timed port-scan being able to cause a denial of service by taking down qemu-nbd before a real client has a chance to connect. Since negotiation is now handled asynchronously via coroutines, we no longer have a synchronous point of return by re-adding a return value to nbd_client_new(). So this patch instead wires things up to pass the negotiation status through the close_fn callback function. Simple test across two terminals: $ qemu-nbd -f raw -p 30001 file $ nmap 127.0.0.1 -p 30001 && \ qemu-io -c 'r 0 512' -f raw nbd://localhost:30001 Note that this patch does not change what constitutes successful negotiation (thus, a client must enter transmission phase before that client can be considered as a reason to terminate the server when the connection ends). Perhaps we may want to tweak things in a later patch to also treat a client that uses NBD_OPT_ABORT as being a 'successful' negotiation (the client correctly talked the NBD protocol, and informed us it was not going to use our export after all), but that's a discussion for another day. Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1451614 Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20170608222617.20376-1-eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-05-09sockets: Limit SocketAddressLegacy to external interfacesMarkus Armbruster1-6/+15
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>
2017-05-09sockets: Rename SocketAddress to SocketAddressLegacyMarkus Armbruster1-3/+3
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>
2017-04-03nbd sockets vnc: Mark problematic address family tests TODOMarkus Armbruster1-0/+1
Certain features make sense only with certain address families. For instance, passing file descriptors requires AF_UNIX. Testing SocketAddress's saddr->type == SOCKET_ADDRESS_KIND_UNIX is obvious, but problematic: it can't recognize AF_UNIX when type == SOCKET_ADDRESS_KIND_FD. Mark such tests of saddr->type TODO. We may want to check the address family with getsockname() there. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gerd Hoffmann <kraxel@redhat.com> Cc: Daniel P. Berrange <berrange@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1490895797-29094-2-git-send-email-armbru@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-01-31trace: switch to modular code generation for sub-directoriesDaniel P. Berrange1-1/+0
Introduce rules in the top level Makefile that are able to generate trace.[ch] files in every subdirectory which has a trace-events file. The top level directory is handled specially, so instead of creating trace.h, it creates trace-root.h. This allows sub-directories to include the top level trace-root.h file, without ambiguity wrt to the trace.g file in the current sub-dir. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 20170125161417.31949-7-berrange@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-27nbd: set name for all I/O channels createdDaniel P. Berrange1-0/+3
Ensure that all I/O channels created for NBD are given names to distinguish their respective roles. Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-09-05nbd-server: Allow node name for nbd-server-addKevin Wolf1-12/+9
There is no reason why an NBD server couldn't be started for any node, even if it's not on the top level. This converts nbd-server-add to accept a node-name. Note that there is a semantic difference between using a BlockBackend name and the node name of its root: In the former case, the NBD server is closed on eject; in the latter case, the NBD server doesn't drop its reference and keeps the image file open this way. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-09-05nbd-server: Use a separate BlockBackendKevin Wolf1-2/+2
The builtin NBD server uses its own BlockBackend now instead of reusing the monitor/guest device one. This means that it has its own writethrough setting now. The builtin NBD server always uses writeback caching now regardless of whether the guest device has WCE enabled. qemu-nbd respects the cache mode given on the command line. We still need to keep a reference to the monitor BB because we put an eject notifier on it, but we don't use it for any I/O. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-02-16nbd: enable use of TLS with nbd-server-start commandDaniel P. Berrange1-22/+100
This modifies the nbd-server-start QMP command so that it is possible to request use of TLS. This is done by adding a new optional parameter "tls-creds" which provides the ID of a previously created QCryptoTLSCreds object instance. TLS is only supported when using an IPv4/IPv6 socket listener. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1455129674-17255-17-git-send-email-berrange@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-16nbd: implement TLS support in the protocol negotiationDaniel P. Berrange1-1/+1
This extends the NBD protocol handling code so that it is capable of negotiating TLS support during the connection setup. This involves requesting the STARTTLS protocol option before any other NBD options. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1455129674-17255-14-git-send-email-berrange@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-16nbd: convert to using I/O channels for actual socket I/ODaniel P. Berrange1-5/+1
Now that all callers are converted to use I/O channels for initial connection setup, it is possible to switch the core NBD protocol handling core over to use QIOChannel APIs for actual sockets I/O. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1455129674-17255-7-git-send-email-berrange@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-16nbd: convert blockdev NBD server to use I/O channels for connection setupDaniel P. Berrange1-15/+34
This converts the blockdev NBD server to use the QIOChannelSocket class for initial listener socket setup and accepting of client connections. Actual I/O is still being performed against the socket file descriptor using the POSIX socket APIs. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1455129674-17255-6-git-send-email-berrange@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-04all: Clean up includesPeter Maydell1-0/+1
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. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Message-id: 1454089805-5470-16-git-send-email-peter.maydell@linaro.org
2016-02-02nbd: Switch from close to eject notifierMax Reitz1-35/+5
The NBD code uses the BDS close notifier to determine when a medium is ejected. However, now it should use the BB's BDS removal notifier for that instead of the BDS's close notifier. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-01-15nbd: Always call "close_fn" in nbd_client_newFam Zheng1-3/+2
Rename the parameter "close" to "close_fn" to disambiguous with close(2). This unifies error handling paths of NBDClient allocation: nbd_client_new will shutdown the socket and call the "close_fn" callback if negotiation failed, so the caller don't need a different path than the normal close. The returned pointer is never used, make it void in preparation for the next patch. Signed-off-by: Fam Zheng <famz@redhat.com> Message-Id: <1452760863-25350-2-git-send-email-famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-22Include monitor/monitor.h exactly where neededMarkus Armbruster1-1/+0
In particular, don't include it into headers. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22qerror: Clean up QERR_ macros to expand into a single stringMarkus Armbruster1-1/+1
These macros expand into error class enumeration constant, comma, string. Unclean. Has been that way since commit 13f59ae. The error class is always ERROR_CLASS_GENERIC_ERROR since the previous commit. Clean up as follows: * Prepend every use of a QERR_ macro by ERROR_CLASS_GENERIC_ERROR, and delete it from the QERR_ macro. No change after preprocessing. * Rewrite error_set(ERROR_CLASS_GENERIC_ERROR, ...) into error_setg(...). Again, no change after preprocessing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22qerror: Eliminate QERR_DEVICE_NOT_FOUNDMarkus Armbruster1-1/+2
Error classes other than ERROR_CLASS_GENERIC_ERROR should not be used in new code. Hiding them in QERR_ macros makes new uses hard to spot. Fortunately, there's just one such macro left. Eliminate it with this coccinelle semantic patch: @@ expression EP, E; @@ -error_set(EP, QERR_DEVICE_NOT_FOUND, E) +error_set(EP, ERROR_CLASS_DEVICE_NOT_FOUND, "Device '%s' not found", E) Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-12Change qemu_set_fd_handler2(..., NULL, ...) to qemu_set_fd_handlerFam Zheng1-2/+2
Done with following Coccinelle semantic patch, plus manual cosmetic changes in net/*.c. @@ expression E1, E2, E3, E4; @@ - qemu_set_fd_handler2(E1, NULL, E2, E3, E4); + qemu_set_fd_handler(E1, E2, E3, E4); Signed-off-by: Fam Zheng <famz@redhat.com> Message-id: 1433400324-7358-8-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-03-25nbd: Fix up comment after commit e140177Markus Armbruster1-2/+3
Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1427271528-11624-1-git-send-email-armbru@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-18nbd: Handle blk_getlength() failureMax Reitz1-1/+5
Signed-off-by: Max Reitz <mreitz@redhat.com> Message-Id: <1424887718-10800-9-git-send-email-mreitz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-10nbd: Change external interface to BlockBackendMax Reitz1-7/+8
Substitute BlockDriverState by BlockBackend in every globally visible function provided by nbd. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 1416309679-333-5-git-send-email-mreitz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-08-20block: Use g_new() & friends where that makes obvious senseMarkus Armbruster1-1/+1
g_new(T, n) is neater than g_malloc(sizeof(T) * n). It's also safer, for two reasons. One, it catches multiplication overflowing size_t. Two, it returns T * rather than void *, which lets the compiler catch more type errors. Patch created with Coccinelle, with two manual changes on top: * Add const to bdrv_iterate_format() to keep the types straight * Convert the allocation in bdrv_drop_intermediate(), which Coccinelle inexplicably misses Coccinelle semantic patch: @@ type T; @@ -g_malloc(sizeof(T)) +g_new(T, 1) @@ type T; @@ -g_try_malloc(sizeof(T)) +g_try_new(T, 1) @@ type T; @@ -g_malloc0(sizeof(T)) +g_new0(T, 1) @@ type T; @@ -g_try_malloc0(sizeof(T)) +g_try_new0(T, 1) @@ type T; expression n; @@ -g_malloc(sizeof(T) * (n)) +g_new(T, n) @@ type T; expression n; @@ -g_try_malloc(sizeof(T) * (n)) +g_try_new(T, n) @@ type T; expression n; @@ -g_malloc0(sizeof(T) * (n)) +g_new0(T, n) @@ type T; expression n; @@ -g_try_malloc0(sizeof(T) * (n)) +g_try_new0(T, n) @@ type T; expression p, n; @@ -g_realloc(p, sizeof(T) * (n)) +g_renew(T, p, n) @@ type T; expression p, n; @@ -g_try_realloc(p, sizeof(T) * (n)) +g_try_renew(T, p, n) Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-06-30nbd: Shutdown socket before closing.Hani Benhabiles1-0/+1
This forces finishing data sending to client before closing the socket like in exports listing or replying with NBD_REP_ERR_UNSUP cases. Signed-off-by: Hani Benhabiles <kroosec@gmail.com> Cc: qemu-stable@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-27nbd: Don't export a block device with no medium.Hani Benhabiles1-0/+4
The device is exported with erroneous values and can't be read. Before the patch: $ sudo nbd-client localhost -p 10809 /dev/nbd0 -name floppy0 Negotiation: ..size = 17592186044415MB bs=1024, sz=18446744073709547520 bytes $ sudo mount /dev/nbd0 /mnt/tmp/ mount: block device /dev/nbd0 is write-protected, mounting read-only mount: /dev/nbd0: can't read superblock After the patch: (qemu) nbd_server_add ide0-hd0 (qemu) nbd_server_add floppy0 Device 'floppy0' has no medium Signed-off-by: Hani Benhabiles <kroosec@gmail.com> Cc: qemu-stable@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-05-24nbd: Close socket on negotiation failure.Hani Benhabiles1-2/+2
Otherwise, the nbd client may hang waiting for the server response. Signed-off-by: Hani Benhabiles <hani@linux.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-09-06nbd: use BlockDriverState refcntFam Zheng1-9/+1
Previously, nbd calls drive_get_ref() on the drive of bs. A BDS doesn't always have associated dinfo, which nbd doesn't care either. We already have BDS ref count, so use it to make it safe for a BDS w/o blockdev. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-04-08hw: move headers to include/Paolo Bonzini1-1/+1
Many of these should be cleaned up with proper qdev-/QOM-ification. Right now there are many catch-all headers in include/hw/ARCH depending on cpu.h, and this makes it necessary to compile these files per-target. However, fixing this does not belong in these patches. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19softmmu: move include files to include/sysemu/Paolo Bonzini1-2/+2
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19misc: move include files to include/qemu/Paolo Bonzini1-1/+1
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19monitor: move include files to include/monitor/Paolo Bonzini1-1/+1
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19block: move include files to include/block/Paolo Bonzini1-1/+1
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19qapi: move include files to include/qobject/Paolo Bonzini1-1/+1
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-11-28nbd-server-add: Fix the default for 'writable'Michal Privoznik1-1/+1
The documentation to this monitor command tells, that 'writable' argument is optional and defaults to false. However, the code sets true as the default. But since some applications may already been using this, it's safer to fix the code and not documentation which would break those applications. Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-11-12nbd: disallow nbd-server-add before nbd-server-startPaolo Bonzini1-0/+5
It works nicely with the QMP commands, but it adds useless complication with HMP. In particular, see the following: (qemu) nbd_server_add -w scsi0-hd0 (qemu) nbd_server_start -a localhost:10809 NBD server already exporting device scsi0-hd0 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-11-12nbd: force read-only export for read-only devicesPaolo Bonzini1-0/+7
This is the desired behavior for HMP, but it is a better choice for QMP as well. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-11-12nbd: fix nbd_server_stop crash when no server was runningPaolo Bonzini1-3/+5
This failed on the new assertion of qemu_set_fd_handler2: qemu-system-x86_64: /home/pbonzini/work/upstream/qemu/iohandler.c:60: qemu_set_fd_handler2: Assertion `fd >= 0' failed. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-10-23qmp: add NBD server commandsPaolo Bonzini1-0/+119
Adding an NBD server inside QEMU is trivial, since all the logic is in nbd.c and can be shared easily between qemu-nbd and QEMU itself. The main difference is that qemu-nbd serves a single unnamed export, while QEMU serves named exports. Acked-by: Luiz Capitulino <lcapitulino@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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