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2016-06-17nbd/client.c: Correct trace format stringPeter Maydell
The trace format string in nbd_send_request uses PRIu16 for request->type, but request->type is a uint32_t. This provokes compiler warnings on the OSX clang. Use PRIu32 instead. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Message-id: 1466167331-17063-1-git-send-email-peter.maydell@linaro.org
2016-06-16nbd: Avoid magic number for NBD max name sizeEric Blake
Declare a constant and use that when determining if an export name fits within the constraints we are willing to support. Note that upstream NBD recently documented that clients MUST support export names of 256 bytes (not including trailing NUL), and SHOULD support names up to 4096 bytes. 4096 is a bit big (we would lose benefits of stack-allocation of a name array), and we already have other limits in place (for example, qcow2 snapshot names are clamped around 1024). So for now, just stick to the required minimum, as that's easier to audit than a full-scale support for larger names. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1463006384-7734-12-git-send-email-eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16nbd: Detect servers that send unexpected error valuesEric Blake
Add some debugging to flag servers that are not compliant to the NBD protocol. This would have flagged the server bug fixed in commit c0301fcc. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Alex Bligh <alex@alex.org.uk> Message-Id: <1463006384-7734-11-git-send-email-eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16nbd: Clean up ioctl handling of qemu-nbd -cEric Blake
The kernel ioctl() interface into NBD is limited to 'unsigned long'; we MUST pass in input with that type (and not int or size_t, as there may be platform ABIs where the wrong types promote incorrectly through var-args). Furthermore, on 32-bit platforms, the kernel is limited to a maximum export size of 2T (our BLKSIZE of 512 times a SIZE_BLOCKS constrained by 32 bit unsigned long). Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1463006384-7734-8-git-send-email-eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16nbd: Group all Linux-specific ioctl code in one placeEric Blake
NBD ioctl()s are used to manage an NBD client session where initial handshake is done in userspace, but then the transmission phase is handed off to the kernel through a /dev/nbdX device. As such, all ioctls sent to the kernel on the /dev/nbdX fd belong in client.c; nbd_disconnect() was out-of-place in server.c. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1463006384-7734-7-git-send-email-eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16nbd: More debug typo fixes, use correct formatsEric Blake
Clean up some debug message oddities missed earlier; this includes some typos, and recognizing that %d is not necessarily compatible with uint32_t. Also add a couple messages that I found useful while debugging things. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1463006384-7734-3-git-send-email-eblake@redhat.com> [Do not use PRIx16, clang complains. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16nbd: Don't use cpu_to_*w() functionsPeter Maydell
The cpu_to_*w() functions just compose a pointer dereference with a byteswap. Instead use st*_p(), which handles potential pointer misalignment and avoids the need to cast the pointer. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Message-Id: <1465575342-12146-1-git-send-email-peter.maydell@linaro.org> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16nbd: Don't use *_to_cpup() functionsPeter Maydell
The *_to_cpup() functions are not very useful, as they simply do a pointer dereference and then a *_to_cpu(). Instead use either: * ld*_*_p(), if the data is at an address that might not be correctly aligned for the load * a local dereference and *_to_cpu(), if the pointer is the correct type and known to be correctly aligned Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Message-Id: <1465570836-22211-1-git-send-email-peter.maydell@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-18Fix some typos found by codespellStefan Weil
Signed-off-by: Stefan Weil <sw@weilnetz.de> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-04-15nbd: Don't fail handshake on NBD_OPT_LIST descriptionsEric Blake
The NBD Protocol states that NBD_REP_SERVER may set 'length > sizeof(namelen) + namelen'; in which case the rest of the packet is a UTF-8 description of the export. While we don't know of any NBD servers that send this description yet, we had better consume the data so we don't choke when we start to talk to such a server. Also, a (buggy/malicious) server that replies with length < sizeof(namelen) would cause us to block waiting for bytes that the server is not sending, and one that replies with super-huge lengths could cause us to temporarily allocate up to 4G memory. Sanity check things before blindly reading incorrectly. Signed-off-by: Eric Blake <eblake@redhat.com> Message-id: 1460077777-31004-1-git-send-email-eblake@redhat.com Reviewed-by: Alex Bligh <alex@alex.org.uk> Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-04-08nbd: Fix NBD unsupported optionsAlex Bligh
nbd-client.c currently fails to handle unsupported options properly. If during option haggling the server finds an option that is unsupported, it returns an NBD_REP_ERR_UNSUP reply. According to nbd's proto.md, the format for such a reply should be: S: 64 bits, 0x3e889045565a9 (magic number for replies) S: 32 bits, the option as sent by the client to which this is a reply S: 32 bits, reply type (e.g., NBD_REP_ACK for successful completion, or NBD_REP_ERR_UNSUP to mark use of an option not known by this server S: 32 bits, length of the reply. This may be zero for some replies, in which case the next field is not sent S: any data as required by the reply (e.g., an export name in the case of NBD_REP_SERVER, or optional UTF-8 message for NBD_REP_ERR_*) However, in nbd-client.c, the reply type was being read, and if it contained an error, it was bailing out and issuing the next option request without first reading the length. This meant that the next option / handshake read had an extra 4 or more bytes of data in it. In practice, this makes Qemu incompatible with servers that do not support NBD_OPT_LIST. To verify this isn't an error in the specification or my reading of it, replies are sent by the reference implementation here: https://github.com/yoe/nbd/blob/66dfb35/nbd-server.c#L1232 and as is evident it always sends a 'datasize' (aka length) 32 bit word. Unsupported elements are replied to here: https://github.com/yoe/nbd/blob/66dfb35/nbd-server.c#L1371 Signed-off-by: Alex Bligh <alex@alex.org.uk> Message-Id: <1459882500-24316-1-git-send-email-alex@alex.org.uk> [rework to ALWAYS consume an optional UTF-8 message from the server] Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1459961962-18771-1-git-send-email-eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-04-08nbd: Improve debug traces on little-endianEric Blake
Print debug tracing messages while data is still in native ordering, rather than after we've potentially swapped it into network order for transmission. Also, it's nice if the server mentions what it is replying, to correlate it to with what the client says it is receiving. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1459913704-19949-4-git-send-email-eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-04-05nbd: Fix poor debug messageEric Blake
The client sends messages to the server, not itself. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1459459222-8637-3-git-send-email-eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22include/qemu/osdep.h: Don't include qapi/error.hMarkus Armbruster
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the Error typedef. Since then, we've moved to include qemu/osdep.h everywhere. Its file comment explains: "To avoid getting into possible circular include dependencies, this file should not include any other QEMU headers, with the exceptions of config-host.h, compiler.h, os-posix.h and os-win32.h, all of which are doing a similar job to this file and are under similar constraints." qapi/error.h doesn't do a similar job, and it doesn't adhere to similar constraints: it includes qapi-types.h. That's in excess of 100KiB of crap most .c files don't actually need. Add the typedef to qemu/typedefs.h, and include that instead of qapi/error.h. Include qapi/error.h in .c files that need it and don't get it now. Include qapi-types.h in qom/object.h for uint16List. Update scripts/clean-includes accordingly. Update it further to match reality: replace config.h by config-target.h, add sysemu/os-posix.h, sysemu/os-win32.h. Update the list of includes in the qemu/osdep.h comment quoted above similarly. This reduces the number of objects depending on qapi/error.h from "all of them" to less than a third. Unfortunately, the number depending on qapi-types.h shrinks only a little. More work is needed for that one. Signed-off-by: Markus Armbruster <armbru@redhat.com> [Fix compilation without the spice devel packages. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-16nbd: implement TLS support in the protocol negotiationDaniel P. Berrange
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: use "" as a default export name if none providedDaniel P. Berrange
If the user does not provide an export name and the server is running the new style protocol, where export names are mandatory, use "" as the default export name if the user has not specified any. "" is defined in the NBD protocol as the default name to use in such scenarios. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1455129674-17255-13-git-send-email-berrange@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-16nbd: always query export list in fixed new style protocolDaniel P. Berrange
With the new style protocol, the NBD client will currenetly send NBD_OPT_EXPORT_NAME as the first (and indeed only) option it wants. The problem is that the NBD protocol spec does not allow for returning an error message with the NBD_OPT_EXPORT_NAME option. So if the server mandates use of TLS, the client will simply see an immediate connection close after issuing NBD_OPT_EXPORT_NAME which is not user friendly. To improve this situation, if we have the fixed new style protocol, we can sent NBD_OPT_LIST as the first option to query the list of server exports. We can check for our named export in this list and raise an error if it is not found, instead of going ahead and sending NBD_OPT_EXPORT_NAME with a name that we know will be rejected. This improves the error reporting both in the case that the server required TLS, and in the case that the client requested export name does not exist on the server. If the server does not support NBD_OPT_LIST, we just ignore that and carry on with NBD_OPT_EXPORT_NAME as before. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1455129674-17255-12-git-send-email-berrange@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-16nbd: make client request fixed new style if advertisedDaniel P. Berrange
If the server advertises support for the fixed new style negotiation, the client should in turn enable new style. This will allow the client to negotiate further NBD options besides the export name. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1455129674-17255-10-git-send-email-berrange@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-16nbd: invert client logic for negotiating protocol versionDaniel P. Berrange
The nbd_receive_negotiate() method takes different code paths based on whether 'name == NULL', and then checks the expected protocol version in each branch. This patch inverts the logic, so that it takes different code paths based on what protocol version it receives and then checks if name is NULL or not as needed. This facilitates later code which allows the client to be capable of using the new style protocol regardless of whether an export name is listed or not. Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1455129674-17255-8-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. Berrange
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>
2016-02-04all: Clean up includesPeter Maydell
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
2016-01-15nbd: Split nbd.cFam Zheng
We have NBD server code and client code, all mixed in a file. Now split them into separate files under nbd/, and update MAINTAINERS. filter_nbd for iotest 083 is updated to keep the log filtered out. Signed-off-by: Fam Zheng <famz@redhat.com> Message-Id: <1452760863-25350-3-git-send-email-famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>