diff options
| -rw-r--r-- | nbd/server.c | 74 |
1 files changed, 46 insertions, 28 deletions
diff --git a/nbd/server.c b/nbd/server.c index 2f03059b4c..cf815603a6 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -253,21 +253,10 @@ static int nbd_negotiate_send_rep_list(QIOChannel *ioc, NBDExport *exp, /* Process the NBD_OPT_LIST command, with a potential series of replies. * Return -errno on error, 0 on success. */ -static int nbd_negotiate_handle_list(NBDClient *client, uint32_t length, - Error **errp) +static int nbd_negotiate_handle_list(NBDClient *client, Error **errp) { NBDExport *exp; - if (length) { - if (nbd_drop(client->ioc, length, errp) < 0) { - return -EIO; - } - return nbd_negotiate_send_rep_err(client->ioc, - NBD_REP_ERR_INVALID, NBD_OPT_LIST, - errp, - "OPT_LIST should not have length"); - } - /* For each export, send a NBD_REP_SERVER reply. */ QTAILQ_FOREACH(exp, &exports, next) { if (nbd_negotiate_send_rep_list(client->ioc, exp, errp)) { @@ -531,7 +520,6 @@ static int nbd_negotiate_handle_info(NBDClient *client, uint32_t length, /* Handle NBD_OPT_STARTTLS. Return NULL to drop connection, or else the * new channel for all further (now-encrypted) communication. */ static QIOChannel *nbd_negotiate_handle_starttls(NBDClient *client, - uint32_t length, Error **errp) { QIOChannel *ioc; @@ -540,15 +528,6 @@ static QIOChannel *nbd_negotiate_handle_starttls(NBDClient *client, trace_nbd_negotiate_handle_starttls(); ioc = client->ioc; - if (length) { - if (nbd_drop(ioc, length, errp) < 0) { - return NULL; - } - nbd_negotiate_send_rep_err(ioc, NBD_REP_ERR_INVALID, NBD_OPT_STARTTLS, - errp, - "OPT_STARTTLS should not have length"); - return NULL; - } if (nbd_negotiate_send_rep(client->ioc, NBD_REP_ACK, NBD_OPT_STARTTLS, errp) < 0) { @@ -584,6 +563,34 @@ static QIOChannel *nbd_negotiate_handle_starttls(NBDClient *client, return QIO_CHANNEL(tioc); } +/* nbd_reject_length: Handle any unexpected payload. + * @fatal requests that we quit talking to the client, even if we are able + * to successfully send an error to the guest. + * Return: + * -errno transmission error occurred or @fatal was requested, errp is set + * 0 error message successfully sent to client, errp is not set + */ +static int nbd_reject_length(NBDClient *client, uint32_t length, + uint32_t option, bool fatal, Error **errp) +{ + int ret; + + assert(length); + if (nbd_drop(client->ioc, length, errp) < 0) { + return -EIO; + } + ret = nbd_negotiate_send_rep_err(client->ioc, NBD_REP_ERR_INVALID, + option, errp, + "option '%s' should have zero length", + nbd_opt_lookup(option)); + if (fatal && !ret) { + error_setg(errp, "option '%s' should have zero length", + nbd_opt_lookup(option)); + return -EINVAL; + } + return ret; +} + /* nbd_negotiate_options * Process all NBD_OPT_* client option commands, during fixed newstyle * negotiation. @@ -674,7 +681,13 @@ static int nbd_negotiate_options(NBDClient *client, uint16_t myflags, } switch (option) { case NBD_OPT_STARTTLS: - tioc = nbd_negotiate_handle_starttls(client, length, errp); + if (length) { + /* Unconditionally drop the connection if the client + * can't start a TLS negotiation correctly */ + return nbd_reject_length(client, length, option, true, + errp); + } + tioc = nbd_negotiate_handle_starttls(client, errp); if (!tioc) { return -EIO; } @@ -710,7 +723,12 @@ static int nbd_negotiate_options(NBDClient *client, uint16_t myflags, } else if (fixedNewstyle) { switch (option) { case NBD_OPT_LIST: - ret = nbd_negotiate_handle_list(client, length, errp); + if (length) { + ret = nbd_reject_length(client, length, option, false, + errp); + } else { + ret = nbd_negotiate_handle_list(client, errp); + } break; case NBD_OPT_ABORT: @@ -736,10 +754,10 @@ static int nbd_negotiate_options(NBDClient *client, uint16_t myflags, break; case NBD_OPT_STARTTLS: - if (nbd_drop(client->ioc, length, errp) < 0) { - return -EIO; - } - if (client->tlscreds) { + if (length) { + ret = nbd_reject_length(client, length, option, false, + errp); + } else if (client->tlscreds) { ret = nbd_negotiate_send_rep_err(client->ioc, NBD_REP_ERR_INVALID, option, errp, |