/* * QEMU Block driver for NBD * * Copyright (C) 2008 Bull S.A.S. * Author: Laurent Vivier <Laurent.Vivier@bull.net> * * Some parts: * Copyright (C) 2007 Anthony Liguori <anthony@codemonkey.ws> * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ #include "qemu/osdep.h" #include "block/nbd-client.h" #include "qapi/error.h" #include "qemu/uri.h" #include "block/block_int.h" #include "qemu/module.h" #include "qapi-visit.h" #include "qapi/qobject-input-visitor.h" #include "qapi/qobject-output-visitor.h" #include "qapi/qmp/qdict.h" #include "qapi/qmp/qjson.h" #include "qapi/qmp/qint.h" #include "qapi/qmp/qstring.h" #include "qemu/cutils.h" #define EN_OPTSTR ":exportname=" typedef struct BDRVNBDState { NbdClientSession client; /* For nbd_refresh_filename() */ SocketAddress *saddr; char *export, *tlscredsid; } BDRVNBDState; static int nbd_parse_uri(const char *filename, QDict *options) { URI *uri; const char *p; QueryParams *qp = NULL; int ret = 0; bool is_unix; uri = uri_parse(filename); if (!uri) { return -EINVAL; } /* transport */ if (!strcmp(uri->scheme, "nbd")) { is_unix = false; } else if (!strcmp(uri->scheme, "nbd+tcp")) { is_unix = false; } else if (!strcmp(uri->scheme, "nbd+unix")) { is_unix = true; } else { ret = -EINVAL; goto out; } p = uri->path ? uri->path : "/"; p += strspn(p, "/"); if (p[0]) { qdict_put(options, "export", qstring_from_str(p)); } qp = query_params_parse(uri->query); if (qp->n > 1 || (is_unix && !qp->n) || (!is_unix && qp->n)) { ret = -EINVAL; goto out; } if (is_unix) { /* nbd+unix:///export?socket=path */ if (uri->server || uri->port || strcmp(qp->p[0].name, "socket")) { ret = -EINVAL; goto out; } qdict_put(options, "server.type", qstring_from_str("unix")); qdict_put(options, "server.data.path", qstring_from_str(qp->p[0].value)); } else { QString *host; char *port_str; /* nbd[+tcp]://host[:port]/export */ if (!uri->server) { ret = -EINVAL; goto out; } /* strip braces from literal IPv6 address */ if (uri->server[0] == '[') { host = qstring_from_substr(uri->server, 1, strlen(uri->server) - 2); } else { host = qstring_from_str(uri->server); } qdict_put(options, "server.type", qstring_from_str("inet")); qdict_put(options, "server.data.host", host); port_str = g_strdup_printf("%d", uri->port ?: NBD_DEFAULT_PORT); qdict_put(options, "server.data.port", qstring_from_str(port_str)); g_free(port_str); } out: if (qp) { query_params_free(qp); } uri_free(uri); return ret; } static bool nbd_has_filename_options_conflict(QDict *options, Error **errp) { const QDictEntry *e; for (e = qdict_first(options); e; e = qdict_next(options, e)) { if (!strcmp(e->key, "host") || !strcmp(e->key, "port") || !strcmp(e->key, "path") || !strcmp(e->key, "export") || strstart(e->key, "server.", NULL)) { error_setg(errp, "Option '%s' cannot be used with a file name", e->key); return true; } } return false; } static void nbd_parse_filename(const char *filename, QDict *options, Error **errp) { char *file; char *export_name; const char *host_spec; const char *unixpath; if (nbd_has_filename_options_conflict(options, errp)) { return; } if (strstr(filename, "://")) { int ret = nbd_parse_uri(filename, options); if (ret < 0) { error_setg(errp, "No valid URL specified"); } return; } file = g_strdup(filename); export_name = strstr(file, EN_OPTSTR); if (export_name) { if (export_name[strlen(EN_OPTSTR)] == 0) { goto out; } export_name[0] = 0; /* truncate 'file' */ export_name += strlen(EN_OPTSTR); qdict_put(options, "export", qstring_from_str(export_name)); } /* extract the host_spec - fail if it's not nbd:... */ if (!strstart(file, "nbd:", &host_spec)) { error_setg(errp, "File name string for NBD must start with 'nbd:'"); goto out; } if (!*host_spec) { goto out; } /* are we a UNIX or TCP socket? */ if (strstart(host_spec, "unix:", &unixpath)) { qdict_put(options, "server.type", qstring_from_str("unix")); qdict_put(options, "server.data.path", qstring_from_str(unixpath)); } else { InetSocketAddress *addr = NULL; addr = inet_parse(host_spec, errp); if (!addr) { goto out; } qdict_put(options, "server.type", qstring_from_str("inet")); qdict_put(options, "server.data.host", qstring_from_str(addr->host)); qdict_put(options, "server.data.port", qstring_from_str(addr->port)); qapi_free_InetSocketAddress(addr); } out: g_free(file); } static bool nbd_process_legacy_socket_options(QDict *output_options, QemuOpts *legacy_opts, Error **errp) { const char *path = qemu_opt_get(legacy_opts, "path"); const char *host = qemu_opt_get(legacy_opts, "host"); const char *port = qemu_opt_get(legacy_opts, "port"); const QDictEntry *e; if (!path && !host && !port) { return true; } for (e = qdict_first(output_options); e; e = qdict_next(output_options, e)) { if (strstart(e->key, "server.", NULL)) { error_setg(errp, "Cannot use 'server' and path/host/port at the " "same time"); return false; } } if (path && host) { error_setg(errp, "path and host may not be used at the same time"); return false; } else if (path) { if (port) { error_setg(errp, "port may not be used without host"); return false; } qdict_put(output_options, "server.type", qstring_from_str("unix")); qdict_put(output_options, "server.data.path", qstring_from_str(path)); } else if (host) { qdict_put(output_options, "server.type", qstring_from_str("inet")); qdict_put(output_options, "server.data.host", qstring_from_str(host)); qdict_put(output_options, "server.data.port", qstring_from_str(port ?: stringify(NBD_DEFAULT_PORT))); } return true; } static SocketAddress *nbd_config(BDRVNBDState *s, QDict *options, Error **errp) { SocketAddress *saddr = NULL; QDict *addr = NULL; QObject *crumpled_addr = NULL; Visitor *iv = NULL; Error *local_err = NULL; qdict_extract_subqdict(options, &addr, "server."); if (!qdict_size(addr)) { error_setg(errp, "NBD server address missing"); goto done; } crumpled_addr = qdict_crumple(addr, errp); if (!crumpled_addr) { goto done; } iv = qobject_input_visitor_new(crumpled_addr, true); visit_type_SocketAddress(iv, NULL, &saddr, &local_err); if (local_err) { error_propagate(errp, local_err); goto done; } s->client.is_unix = saddr->type == SOCKET_ADDRESS_KIND_UNIX; done: QDECREF(addr); qobject_decref(crumpled_addr); visit_free(iv); return saddr; } NbdClientSession *nbd_get_client_session(BlockDriverState *bs) { BDRVNBDState *s = bs->opaque; return &s->client; } static QIOChannelSocket *nbd_establish_connection(SocketAddress *saddr, Error **errp) { QIOChannelSocket *sioc; Error *local_err = NULL; sioc = qio_channel_socket_new(); qio_channel_set_name(QIO_CHANNEL(sioc), "nbd-client"); qio_channel_socket_connect_sync(sioc, saddr, &local_err); if (local_err) { error_propagate(errp, local_err); return NULL; } qio_channel_set_delay(QIO_CHANNEL(sioc), false); return sioc; } static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) { Object *obj; QCryptoTLSCreds *creds; obj = object_resolve_path_component( object_get_objects_root(), id); if (!obj) { error_setg(errp, "No TLS credentials with id '%s'", id); return NULL; } creds = (QCryptoTLSCreds *) object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS); if (!creds) { error_setg(errp, "Object with id '%s' is not TLS credentials", id); return NULL; } if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) { error_setg(errp, "Expecting TLS credentials with a client endpoint"); return NULL; } object_ref(obj); return creds; } static QemuOptsList nbd_runtime_opts = { .name = "nbd", .head = QTAILQ_HEAD_INITIALIZER(nbd_runtime_opts.head), .desc = { { .name = "host", .type = QEMU_OPT_STRING, .help = "TCP host to connect to", }, { .name = "port", .type = QEMU_OPT_STRING, .help = "TCP port to connect to", }, { .name = "path", .type = QEMU_OPT_STRING, .help = "Unix socket path to connect to", }, { .name = "export", .type = QEMU_OPT_STRING, .help = "Name of the NBD export to open", }, { .name = "tls-creds", .type = QEMU_OPT_STRING, .help = "ID of the TLS credentials to use", }, }, }; static int nbd_open(BlockDriverState *bs, QDict *options, int flags, Error **errp) { BDRVNBDState *s = bs->opaque; QemuOpts *opts = NULL; Error *local_err = NULL; QIOChannelSocket *sioc = NULL; QCryptoTLSCreds *tlscreds = NULL; const char *hostname = NULL; int ret = -EINVAL; opts = qemu_opts_create(&nbd_runtime_opts, NULL, 0, &error_abort); qemu_opts_absorb_qdict(opts, options, &local_err); if (local_err) { error_propagate(errp, local_err); goto error; } /* Translate @host, @port, and @path to a SocketAddress */ if (!nbd_process_legacy_socket_options(options, opts, errp)) { goto error; } /* Pop the config into our state object. Exit if invalid. */ s->saddr = nbd_config(s, options, errp); if (!s->saddr) { goto error; } s->export = g_strdup(qemu_opt_get(opts, "export")); s->tlscredsid = g_strdup(qemu_opt_get(opts, "tls-creds")); if (s->tlscredsid) { tlscreds = nbd_get_tls_creds(s->tlscredsid, errp); if (!tlscreds) { goto error; } if (s->saddr->type != SOCKET_ADDRESS_KIND_INET) { error_setg(errp, "TLS only supported over IP sockets"); goto error; } hostname = s->saddr->u.inet.data->host; } /* establish TCP connection, return error if it fails * TODO: Configurable retry-until-timeout behaviour. */ sioc = nbd_establish_connection(s->saddr, errp); if (!sioc) { ret = -ECONNREFUSED; goto error; } /* NBD handshake */ ret = nbd_client_init(bs, sioc, s->export, tlscreds, hostname, errp); error: if (sioc) { object_unref(OBJECT(sioc)); } if (tlscreds) { object_unref(OBJECT(tlscreds)); } if (ret < 0) { qapi_free_SocketAddress(s->saddr); g_free(s->export); g_free(s->tlscredsid); } qemu_opts_del(opts); return ret; } static int nbd_co_flush(BlockDriverState *bs) { return nbd_client_co_flush(bs); } static void nbd_refresh_limits(BlockDriverState *bs, Error **errp) { bs->bl.max_pdiscard = NBD_MAX_BUFFER_SIZE; bs->bl.max_transfer = NBD_MAX_BUFFER_SIZE; } static void nbd_close(BlockDriverState *bs) { BDRVNBDState *s = bs->opaque; nbd_client_close(bs); qapi_free_SocketAddress(s->saddr); g_free(s->export); g_free(s->tlscredsid); } static int64_t nbd_getlength(BlockDriverState *bs) { BDRVNBDState *s = bs->opaque; return s->client.size; } static void nbd_detach_aio_context(BlockDriverState *bs) { nbd_client_detach_aio_context(bs); } static void nbd_attach_aio_context(BlockDriverState *bs, AioContext *new_context) { nbd_client_attach_aio_context(bs, new_context); } static void nbd_refresh_filename(BlockDriverState *bs, QDict *options) { BDRVNBDState *s = bs->opaque; QDict *opts = qdict_new(); QObject *saddr_qdict; Visitor *ov; const char *host = NULL, *port = NULL, *path = NULL; if (s->saddr->type == SOCKET_ADDRESS_KIND_INET) { const InetSocketAddress *inet = s->saddr->u.inet.data; if (!inet->has_ipv4 && !inet->has_ipv6 && !inet->has_to) { host = inet->host; port = inet->port; } } else if (s->saddr->type == SOCKET_ADDRESS_KIND_UNIX) { path = s->saddr->u.q_unix.data->path; } qdict_put(opts, "driver", qstring_from_str("nbd")); if (path && s->export) { snprintf(bs->exact_filename, sizeof(bs->exact_filename), "nbd+unix:///%s?socket=%s", s->export, path); } else if (path && !s->export) { snprintf(bs->exact_filename, sizeof(bs->exact_filename), "nbd+unix://?socket=%s", path); } else if (host && s->export) { snprintf(bs->exact_filename, sizeof(bs->exact_filename), "nbd://%s:%s/%s", host, port, s->export); } else if (host && !s->export) { snprintf(bs->exact_filename, sizeof(bs->exact_filename), "nbd://%s:%s", host, port); } ov = qobject_output_visitor_new(&saddr_qdict); visit_type_SocketAddress(ov, NULL, &s->saddr, &error_abort); visit_complete(ov, &saddr_qdict); assert(qobject_type(saddr_qdict) == QTYPE_QDICT); qdict_put_obj(opts, "server", saddr_qdict); if (s->export) { qdict_put(opts, "export", qstring_from_str(s->export)); } if (s->tlscredsid) { qdict_put(opts, "tls-creds", qstring_from_str(s->tlscredsid)); } qdict_flatten(opts); bs->full_open_options = opts; } static BlockDriver bdrv_nbd = { .format_name = "nbd", .protocol_name = "nbd", .instance_size = sizeof(BDRVNBDState), .bdrv_parse_filename = nbd_parse_filename, .bdrv_file_open = nbd_open, .bdrv_co_preadv = nbd_client_co_preadv, .bdrv_co_pwritev = nbd_client_co_pwritev, .bdrv_close = nbd_close, .bdrv_co_flush_to_os = nbd_co_flush, .bdrv_co_pdiscard = nbd_client_co_pdiscard, .bdrv_refresh_limits = nbd_refresh_limits, .bdrv_getlength = nbd_getlength, .bdrv_detach_aio_context = nbd_detach_aio_context, .bdrv_attach_aio_context = nbd_attach_aio_context, .bdrv_refresh_filename = nbd_refresh_filename, }; static BlockDriver bdrv_nbd_tcp = { .format_name = "nbd", .protocol_name = "nbd+tcp", .instance_size = sizeof(BDRVNBDState), .bdrv_parse_filename = nbd_parse_filename, .bdrv_file_open = nbd_open, .bdrv_co_preadv = nbd_client_co_preadv, .bdrv_co_pwritev = nbd_client_co_pwritev, .bdrv_close = nbd_close, .bdrv_co_flush_to_os = nbd_co_flush, .bdrv_co_pdiscard = nbd_client_co_pdiscard, .bdrv_refresh_limits = nbd_refresh_limits, .bdrv_getlength = nbd_getlength, .bdrv_detach_aio_context = nbd_detach_aio_context, .bdrv_attach_aio_context = nbd_attach_aio_context, .bdrv_refresh_filename = nbd_refresh_filename, }; static BlockDriver bdrv_nbd_unix = { .format_name = "nbd", .protocol_name = "nbd+unix", .instance_size = sizeof(BDRVNBDState), .bdrv_parse_filename = nbd_parse_filename, .bdrv_file_open = nbd_open, .bdrv_co_preadv = nbd_client_co_preadv, .bdrv_co_pwritev = nbd_client_co_pwritev, .bdrv_close = nbd_close, .bdrv_co_flush_to_os = nbd_co_flush, .bdrv_co_pdiscard = nbd_client_co_pdiscard, .bdrv_refresh_limits = nbd_refresh_limits, .bdrv_getlength = nbd_getlength, .bdrv_detach_aio_context = nbd_detach_aio_context, .bdrv_attach_aio_context = nbd_attach_aio_context, .bdrv_refresh_filename = nbd_refresh_filename, }; static void bdrv_nbd_init(void) { bdrv_register(&bdrv_nbd); bdrv_register(&bdrv_nbd_tcp); bdrv_register(&bdrv_nbd_unix); } block_init(bdrv_nbd_init);