diff options
author | Daniel P. Berrange <berrange@redhat.com> | 2016-02-10 18:41:06 +0000 |
---|---|---|
committer | Timothy Pearson <tpearson@raptorengineering.com> | 2019-11-29 19:45:29 -0600 |
commit | 93dfc919d47da6f6329d29f4943ae0259279771f (patch) | |
tree | b46486d7516959c63faf7711732bc0d09ef0dcc1 /nbd/server.c | |
parent | c04b9df32b92b17fa33e4079fcbf8c0dfe7e76da (diff) | |
download | hqemu-93dfc919d47da6f6329d29f4943ae0259279771f.zip hqemu-93dfc919d47da6f6329d29f4943ae0259279771f.tar.gz |
nbd: make server compliant with fixed newstyle spec
If the client does not request the fixed new style protocol,
then we should only accept NBD_OPT_EXPORT_NAME. All other
options are only valid when fixed new style has been activated.
The qemu-nbd client doesn't currently request fixed new style
protocol, but this change won't break qemu-nbd, because it
fortunately only ever uses NBD_OPT_EXPORT_NAME, so was never
triggering the non-compliant server behaviour.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-9-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'nbd/server.c')
-rw-r--r-- | nbd/server.c | 69 |
1 files changed, 46 insertions, 23 deletions
diff --git a/nbd/server.c b/nbd/server.c index 15aa03d..074a1e6 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -310,6 +310,7 @@ fail: static int nbd_negotiate_options(NBDClient *client) { uint32_t flags; + bool fixedNewstyle = false; /* Client sends: [ 0 .. 3] client flags @@ -332,14 +333,19 @@ static int nbd_negotiate_options(NBDClient *client) } TRACE("Checking client flags"); be32_to_cpus(&flags); - if (flags != 0 && flags != NBD_FLAG_C_FIXED_NEWSTYLE) { - LOG("Bad client flags received"); + if (flags & NBD_FLAG_C_FIXED_NEWSTYLE) { + TRACE("Support supports fixed newstyle handshake"); + fixedNewstyle = true; + flags &= ~NBD_FLAG_C_FIXED_NEWSTYLE; + } + if (flags != 0) { + TRACE("Unknown client flags 0x%x received", flags); return -EIO; } while (1) { int ret; - uint32_t tmp, length; + uint32_t clientflags, length; uint64_t magic; if (nbd_negotiate_read(client->ioc, &magic, sizeof(magic)) != @@ -353,10 +359,12 @@ static int nbd_negotiate_options(NBDClient *client) return -EINVAL; } - if (nbd_negotiate_read(client->ioc, &tmp, sizeof(tmp)) != sizeof(tmp)) { + if (nbd_negotiate_read(client->ioc, &clientflags, + sizeof(clientflags)) != sizeof(clientflags)) { LOG("read failed"); return -EINVAL; } + clientflags = be32_to_cpu(clientflags); if (nbd_negotiate_read(client->ioc, &length, sizeof(length)) != sizeof(length)) { @@ -365,26 +373,41 @@ static int nbd_negotiate_options(NBDClient *client) } length = be32_to_cpu(length); - TRACE("Checking option"); - switch (be32_to_cpu(tmp)) { - case NBD_OPT_LIST: - ret = nbd_negotiate_handle_list(client, length); - if (ret < 0) { - return ret; + TRACE("Checking option 0x%x", clientflags); + if (fixedNewstyle) { + switch (clientflags) { + case NBD_OPT_LIST: + ret = nbd_negotiate_handle_list(client, length); + if (ret < 0) { + return ret; + } + break; + + case NBD_OPT_ABORT: + return -EINVAL; + + case NBD_OPT_EXPORT_NAME: + return nbd_negotiate_handle_export_name(client, length); + + default: + TRACE("Unsupported option 0x%x", clientflags); + nbd_negotiate_send_rep(client->ioc, NBD_REP_ERR_UNSUP, + clientflags); + return -EINVAL; + } + } else { + /* + * If broken new-style we should drop the connection + * for anything except NBD_OPT_EXPORT_NAME + */ + switch (clientflags) { + case NBD_OPT_EXPORT_NAME: + return nbd_negotiate_handle_export_name(client, length); + + default: + TRACE("Unsupported option 0x%x", clientflags); + return -EINVAL; } - break; - - case NBD_OPT_ABORT: - return -EINVAL; - - case NBD_OPT_EXPORT_NAME: - return nbd_negotiate_handle_export_name(client, length); - - default: - tmp = be32_to_cpu(tmp); - LOG("Unsupported option 0x%x", tmp); - nbd_negotiate_send_rep(client->ioc, NBD_REP_ERR_UNSUP, tmp); - return -EINVAL; } } } |