コード例 #1
0
ファイル: client.c プロジェクト: 8tab/qemu
/* Receive the header of an option reply, which should match the given
 * opt.  Read through the length field, but NOT the length bytes of
 * payload. Return 0 if successful, -1 with errp set if it is
 * impossible to continue. */
static int nbd_receive_option_reply(QIOChannel *ioc, uint32_t opt,
                                    nbd_opt_reply *reply, Error **errp)
{
    QEMU_BUILD_BUG_ON(sizeof(*reply) != 20);
    if (nbd_read(ioc, reply, sizeof(*reply), errp) < 0) {
        error_prepend(errp, "failed to read option reply");
        nbd_send_opt_abort(ioc);
        return -1;
    }
    be64_to_cpus(&reply->magic);
    be32_to_cpus(&reply->option);
    be32_to_cpus(&reply->type);
    be32_to_cpus(&reply->length);

    trace_nbd_receive_option_reply(reply->option, nbd_opt_lookup(reply->option),
                                   reply->type, nbd_rep_lookup(reply->type),
                                   reply->length);

    if (reply->magic != NBD_REP_MAGIC) {
        error_setg(errp, "Unexpected option reply magic");
        nbd_send_opt_abort(ioc);
        return -1;
    }
    if (reply->option != opt) {
        error_setg(errp, "Unexpected option type %x expected %x",
                   reply->option, opt);
        nbd_send_opt_abort(ioc);
        return -1;
    }
    return 0;
}
コード例 #2
0
ファイル: client.c プロジェクト: nikunjad/qemu
/* nbd_request_simple_option: Send an option request, and parse the reply
 * return 1 for successful negotiation,
 *        0 if operation is unsupported,
 *        -1 with errp set for any other error
 */
static int nbd_request_simple_option(QIOChannel *ioc, int opt, Error **errp)
{
    NBDOptionReply reply;
    int error;

    if (nbd_send_option_request(ioc, opt, 0, NULL, errp) < 0) {
        return -1;
    }

    if (nbd_receive_option_reply(ioc, opt, &reply, errp) < 0) {
        return -1;
    }
    error = nbd_handle_reply_err(ioc, &reply, errp);
    if (error <= 0) {
        return error;
    }

    if (reply.type != NBD_REP_ACK) {
        error_setg(errp, "Server answered option %d (%s) with unexpected "
                   "reply %" PRIu32 " (%s)", opt, nbd_opt_lookup(opt),
                   reply.type, nbd_rep_lookup(reply.type));
        nbd_send_opt_abort(ioc);
        return -1;
    }

    if (reply.length != 0) {
        error_setg(errp, "Option %d ('%s') response length is %" PRIu32
                   " (it should be zero)", opt, nbd_opt_lookup(opt),
                   reply.length);
        nbd_send_opt_abort(ioc);
        return -1;
    }

    return 1;
}
コード例 #3
0
ファイル: client.c プロジェクト: 8tab/qemu
static QIOChannel *nbd_receive_starttls(QIOChannel *ioc,
                                        QCryptoTLSCreds *tlscreds,
                                        const char *hostname, Error **errp)
{
    nbd_opt_reply reply;
    QIOChannelTLS *tioc;
    struct NBDTLSHandshakeData data = { 0 };

    trace_nbd_receive_starttls_request();
    if (nbd_send_option_request(ioc, NBD_OPT_STARTTLS, 0, NULL, errp) < 0) {
        return NULL;
    }

    trace_nbd_receive_starttls_reply();
    if (nbd_receive_option_reply(ioc, NBD_OPT_STARTTLS, &reply, errp) < 0) {
        return NULL;
    }

    if (reply.type != NBD_REP_ACK) {
        error_setg(errp, "Server rejected request to start TLS %" PRIx32,
                   reply.type);
        nbd_send_opt_abort(ioc);
        return NULL;
    }

    if (reply.length != 0) {
        error_setg(errp, "Start TLS response was not zero %" PRIu32,
                   reply.length);
        nbd_send_opt_abort(ioc);
        return NULL;
    }

    trace_nbd_receive_starttls_new_client();
    tioc = qio_channel_tls_new_client(ioc, tlscreds, hostname, errp);
    if (!tioc) {
        return NULL;
    }
    qio_channel_set_name(QIO_CHANNEL(tioc), "nbd-client-tls");
    data.loop = g_main_loop_new(g_main_context_default(), FALSE);
    trace_nbd_receive_starttls_tls_handshake();
    qio_channel_tls_handshake(tioc,
                              nbd_tls_handshake,
                              &data,
                              NULL);

    if (!data.complete) {
        g_main_loop_run(data.loop);
    }
    g_main_loop_unref(data.loop);
    if (data.error) {
        error_propagate(errp, data.error);
        object_unref(OBJECT(tioc));
        return NULL;
    }

    return QIO_CHANNEL(tioc);
}
コード例 #4
0
ファイル: client.c プロジェクト: 8tab/qemu
/* Return -1 on failure, 0 if wantname is an available export. */
static int nbd_receive_query_exports(QIOChannel *ioc,
                                     const char *wantname,
                                     Error **errp)
{
    bool foundExport = false;

    trace_nbd_receive_query_exports_start(wantname);
    if (nbd_send_option_request(ioc, NBD_OPT_LIST, 0, NULL, errp) < 0) {
        return -1;
    }

    while (1) {
        int ret = nbd_receive_list(ioc, wantname, &foundExport, errp);

        if (ret < 0) {
            /* Server gave unexpected reply */
            return -1;
        } else if (ret == 0) {
            /* Done iterating. */
            if (!foundExport) {
                error_setg(errp, "No export with name '%s' available",
                           wantname);
                nbd_send_opt_abort(ioc);
                return -1;
            }
            trace_nbd_receive_query_exports_success(wantname);
            return 0;
        }
    }
}
コード例 #5
0
ファイル: client.c プロジェクト: nikunjad/qemu
static QIOChannel *nbd_receive_starttls(QIOChannel *ioc,
                                        QCryptoTLSCreds *tlscreds,
                                        const char *hostname, Error **errp)
{
    int ret;
    QIOChannelTLS *tioc;
    struct NBDTLSHandshakeData data = { 0 };

    ret = nbd_request_simple_option(ioc, NBD_OPT_STARTTLS, errp);
    if (ret <= 0) {
        if (ret == 0) {
            error_setg(errp, "Server don't support STARTTLS option");
            nbd_send_opt_abort(ioc);
        }
        return NULL;
    }

    trace_nbd_receive_starttls_new_client();
    tioc = qio_channel_tls_new_client(ioc, tlscreds, hostname, errp);
    if (!tioc) {
        return NULL;
    }
    qio_channel_set_name(QIO_CHANNEL(tioc), "nbd-client-tls");
    data.loop = g_main_loop_new(g_main_context_default(), FALSE);
    trace_nbd_receive_starttls_tls_handshake();
    qio_channel_tls_handshake(tioc,
                              nbd_tls_handshake,
                              &data,
                              NULL);

    if (!data.complete) {
        g_main_loop_run(data.loop);
    }
    g_main_loop_unref(data.loop);
    if (data.error) {
        error_propagate(errp, data.error);
        object_unref(OBJECT(tioc));
        return NULL;
    }

    return QIO_CHANNEL(tioc);
}
コード例 #6
0
ファイル: client.c プロジェクト: 8tab/qemu
/* Returns -1 if NBD_OPT_GO proves the export @wantname cannot be
 * used, 0 if NBD_OPT_GO is unsupported (fall back to NBD_OPT_LIST and
 * NBD_OPT_EXPORT_NAME in that case), and > 0 if the export is good to
 * go (with @info populated). */
static int nbd_opt_go(QIOChannel *ioc, const char *wantname,
                      NBDExportInfo *info, Error **errp)
{
    nbd_opt_reply reply;
    uint32_t len = strlen(wantname);
    uint16_t type;
    int error;
    char *buf;

    /* The protocol requires that the server send NBD_INFO_EXPORT with
     * a non-zero flags (at least NBD_FLAG_HAS_FLAGS must be set); so
     * flags still 0 is a witness of a broken server. */
    info->flags = 0;

    trace_nbd_opt_go_start(wantname);
    buf = g_malloc(4 + len + 2 + 2 * info->request_sizes + 1);
    stl_be_p(buf, len);
    memcpy(buf + 4, wantname, len);
    /* At most one request, everything else up to server */
    stw_be_p(buf + 4 + len, info->request_sizes);
    if (info->request_sizes) {
        stw_be_p(buf + 4 + len + 2, NBD_INFO_BLOCK_SIZE);
    }
    error = nbd_send_option_request(ioc, NBD_OPT_GO,
                                    4 + len + 2 + 2 * info->request_sizes,
                                    buf, errp);
    g_free(buf);
    if (error < 0) {
        return -1;
    }

    while (1) {
        if (nbd_receive_option_reply(ioc, NBD_OPT_GO, &reply, errp) < 0) {
            return -1;
        }
        error = nbd_handle_reply_err(ioc, &reply, errp);
        if (error <= 0) {
            return error;
        }
        len = reply.length;

        if (reply.type == NBD_REP_ACK) {
            /* Server is done sending info and moved into transmission
               phase, but make sure it sent flags */
            if (len) {
                error_setg(errp, "server sent invalid NBD_REP_ACK");
                return -1;
            }
            if (!info->flags) {
                error_setg(errp, "broken server omitted NBD_INFO_EXPORT");
                return -1;
            }
            trace_nbd_opt_go_success();
            return 1;
        }
        if (reply.type != NBD_REP_INFO) {
            error_setg(errp, "unexpected reply type %" PRIx32
                       " (%s), expected %x",
                       reply.type, nbd_rep_lookup(reply.type), NBD_REP_INFO);
            nbd_send_opt_abort(ioc);
            return -1;
        }
        if (len < sizeof(type)) {
            error_setg(errp, "NBD_REP_INFO length %" PRIu32 " is too short",
                       len);
            nbd_send_opt_abort(ioc);
            return -1;
        }
        if (nbd_read(ioc, &type, sizeof(type), errp) < 0) {
            error_prepend(errp, "failed to read info type");
            nbd_send_opt_abort(ioc);
            return -1;
        }
        len -= sizeof(type);
        be16_to_cpus(&type);
        switch (type) {
        case NBD_INFO_EXPORT:
            if (len != sizeof(info->size) + sizeof(info->flags)) {
                error_setg(errp, "remaining export info len %" PRIu32
                           " is unexpected size", len);
                nbd_send_opt_abort(ioc);
                return -1;
            }
            if (nbd_read(ioc, &info->size, sizeof(info->size), errp) < 0) {
                error_prepend(errp, "failed to read info size");
                nbd_send_opt_abort(ioc);
                return -1;
            }
            be64_to_cpus(&info->size);
            if (nbd_read(ioc, &info->flags, sizeof(info->flags), errp) < 0) {
                error_prepend(errp, "failed to read info flags");
                nbd_send_opt_abort(ioc);
                return -1;
            }
            be16_to_cpus(&info->flags);
            trace_nbd_receive_negotiate_size_flags(info->size, info->flags);
            break;

        case NBD_INFO_BLOCK_SIZE:
            if (len != sizeof(info->min_block) * 3) {
                error_setg(errp, "remaining export info len %" PRIu32
                           " is unexpected size", len);
                nbd_send_opt_abort(ioc);
                return -1;
            }
            if (nbd_read(ioc, &info->min_block, sizeof(info->min_block),
                         errp) < 0) {
                error_prepend(errp, "failed to read info minimum block size");
                nbd_send_opt_abort(ioc);
                return -1;
            }
            be32_to_cpus(&info->min_block);
            if (!is_power_of_2(info->min_block)) {
                error_setg(errp, "server minimum block size %" PRId32
                           "is not a power of two", info->min_block);
                nbd_send_opt_abort(ioc);
                return -1;
            }
            if (nbd_read(ioc, &info->opt_block, sizeof(info->opt_block),
                         errp) < 0) {
                error_prepend(errp, "failed to read info preferred block size");
                nbd_send_opt_abort(ioc);
                return -1;
            }
            be32_to_cpus(&info->opt_block);
            if (!is_power_of_2(info->opt_block) ||
                info->opt_block < info->min_block) {
                error_setg(errp, "server preferred block size %" PRId32
                           "is not valid", info->opt_block);
                nbd_send_opt_abort(ioc);
                return -1;
            }
            if (nbd_read(ioc, &info->max_block, sizeof(info->max_block),
                         errp) < 0) {
                error_prepend(errp, "failed to read info maximum block size");
                nbd_send_opt_abort(ioc);
                return -1;
            }
            be32_to_cpus(&info->max_block);
            trace_nbd_opt_go_info_block_size(info->min_block, info->opt_block,
                                             info->max_block);
            break;

        default:
            trace_nbd_opt_go_info_unknown(type, nbd_info_lookup(type));
            if (nbd_drop(ioc, len, errp) < 0) {
                error_prepend(errp, "Failed to read info payload");
                nbd_send_opt_abort(ioc);
                return -1;
            }
            break;
        }
    }
}
コード例 #7
0
ファイル: client.c プロジェクト: 8tab/qemu
/* Process another portion of the NBD_OPT_LIST reply.  Set *@match if
 * the current reply matches @want or if the server does not support
 * NBD_OPT_LIST, otherwise leave @match alone.  Return 0 if iteration
 * is complete, positive if more replies are expected, or negative
 * with @errp set if an unrecoverable error occurred. */
static int nbd_receive_list(QIOChannel *ioc, const char *want, bool *match,
                            Error **errp)
{
    nbd_opt_reply reply;
    uint32_t len;
    uint32_t namelen;
    char name[NBD_MAX_NAME_SIZE + 1];
    int error;

    if (nbd_receive_option_reply(ioc, NBD_OPT_LIST, &reply, errp) < 0) {
        return -1;
    }
    error = nbd_handle_reply_err(ioc, &reply, errp);
    if (error <= 0) {
        /* The server did not support NBD_OPT_LIST, so set *match on
         * the assumption that any name will be accepted.  */
        *match = true;
        return error;
    }
    len = reply.length;

    if (reply.type == NBD_REP_ACK) {
        if (len != 0) {
            error_setg(errp, "length too long for option end");
            nbd_send_opt_abort(ioc);
            return -1;
        }
        return 0;
    } else if (reply.type != NBD_REP_SERVER) {
        error_setg(errp, "Unexpected reply type %" PRIx32 " expected %x",
                   reply.type, NBD_REP_SERVER);
        nbd_send_opt_abort(ioc);
        return -1;
    }

    if (len < sizeof(namelen) || len > NBD_MAX_BUFFER_SIZE) {
        error_setg(errp, "incorrect option length %" PRIu32, len);
        nbd_send_opt_abort(ioc);
        return -1;
    }
    if (nbd_read(ioc, &namelen, sizeof(namelen), errp) < 0) {
        error_prepend(errp, "failed to read option name length");
        nbd_send_opt_abort(ioc);
        return -1;
    }
    namelen = be32_to_cpu(namelen);
    len -= sizeof(namelen);
    if (len < namelen) {
        error_setg(errp, "incorrect option name length");
        nbd_send_opt_abort(ioc);
        return -1;
    }
    if (namelen != strlen(want)) {
        if (nbd_drop(ioc, len, errp) < 0) {
            error_prepend(errp, "failed to skip export name with wrong length");
            nbd_send_opt_abort(ioc);
            return -1;
        }
        return 1;
    }

    assert(namelen < sizeof(name));
    if (nbd_read(ioc, name, namelen, errp) < 0) {
        error_prepend(errp, "failed to read export name");
        nbd_send_opt_abort(ioc);
        return -1;
    }
    name[namelen] = '\0';
    len -= namelen;
    if (nbd_drop(ioc, len, errp) < 0) {
        error_prepend(errp, "failed to read export description");
        nbd_send_opt_abort(ioc);
        return -1;
    }
    if (!strcmp(name, want)) {
        *match = true;
    }
    return 1;
}
コード例 #8
0
ファイル: client.c プロジェクト: 8tab/qemu
/* If reply represents success, return 1 without further action.
 * If reply represents an error, consume the optional payload of
 * the packet on ioc.  Then return 0 for unsupported (so the client
 * can fall back to other approaches), or -1 with errp set for other
 * errors.
 */
static int nbd_handle_reply_err(QIOChannel *ioc, nbd_opt_reply *reply,
                                Error **errp)
{
    char *msg = NULL;
    int result = -1;

    if (!(reply->type & (1 << 31))) {
        return 1;
    }

    if (reply->length) {
        if (reply->length > NBD_MAX_BUFFER_SIZE) {
            error_setg(errp, "server error 0x%" PRIx32
                       " (%s) message is too long",
                       reply->type, nbd_rep_lookup(reply->type));
            goto cleanup;
        }
        msg = g_malloc(reply->length + 1);
        if (nbd_read(ioc, msg, reply->length, errp) < 0) {
            error_prepend(errp, "failed to read option error 0x%" PRIx32
                          " (%s) message",
                          reply->type, nbd_rep_lookup(reply->type));
            goto cleanup;
        }
        msg[reply->length] = '\0';
    }

    switch (reply->type) {
    case NBD_REP_ERR_UNSUP:
        trace_nbd_reply_err_unsup(reply->option, nbd_opt_lookup(reply->option));
        result = 0;
        goto cleanup;

    case NBD_REP_ERR_POLICY:
        error_setg(errp, "Denied by server for option %" PRIx32 " (%s)",
                   reply->option, nbd_opt_lookup(reply->option));
        break;

    case NBD_REP_ERR_INVALID:
        error_setg(errp, "Invalid data length for option %" PRIx32 " (%s)",
                   reply->option, nbd_opt_lookup(reply->option));
        break;

    case NBD_REP_ERR_PLATFORM:
        error_setg(errp, "Server lacks support for option %" PRIx32 " (%s)",
                   reply->option, nbd_opt_lookup(reply->option));
        break;

    case NBD_REP_ERR_TLS_REQD:
        error_setg(errp, "TLS negotiation required before option %" PRIx32
                   " (%s)", reply->option, nbd_opt_lookup(reply->option));
        break;

    case NBD_REP_ERR_UNKNOWN:
        error_setg(errp, "Requested export not available");
        break;

    case NBD_REP_ERR_SHUTDOWN:
        error_setg(errp, "Server shutting down before option %" PRIx32 " (%s)",
                   reply->option, nbd_opt_lookup(reply->option));
        break;

    case NBD_REP_ERR_BLOCK_SIZE_REQD:
        error_setg(errp, "Server requires INFO_BLOCK_SIZE for option %" PRIx32
                   " (%s)", reply->option, nbd_opt_lookup(reply->option));
        break;

    default:
        error_setg(errp, "Unknown error code when asking for option %" PRIx32
                   " (%s)", reply->option, nbd_opt_lookup(reply->option));
        break;
    }

    if (msg) {
        error_append_hint(errp, "server reported: %s\n", msg);
    }

 cleanup:
    g_free(msg);
    if (result < 0) {
        nbd_send_opt_abort(ioc);
    }
    return result;
}