diff --git a/docs/manpages/virsh.rst b/docs/manpages/virsh.rst index a0d6c3fadd..ca5acf84ca 100644 --- a/docs/manpages/virsh.rst +++ b/docs/manpages/virsh.rst @@ -3270,6 +3270,14 @@ There are a few scenarios where specifying *migrateuri* may help: might be specified to choose a specific port number outside the default range in order to comply with local firewall policies. +* The *desturi* uses UNIX transport method. In this advanced case libvirt + should not guess a *migrateuri* and it should be specified using + UNIX socket path URI: + +.. code-block:: + + unix:///path/to/socket + See `https://libvirt.org/migration.html#uris `_ for more details on migration URIs. @@ -3296,8 +3304,9 @@ specific parameters separated by '&'. Currently recognized parameters are Optional *listen-address* sets the listen address that hypervisor on the destination side should bind to for incoming migration. Both IPv4 and IPv6 addresses are accepted as well as hostnames (the resolving is done on -destination). Some hypervisors do not support this feature and will return an -error if this parameter is used. +destination). Some hypervisors do not support specifying the listen address and +will return an error if this parameter is used. This parameter cannot be used if +*desturi* uses UNIX transport method. Optional *disks-port* sets the port that hypervisor on destination side should bind to for incoming disks traffic. Currently it is supported only by QEMU. diff --git a/docs/migration.html.in b/docs/migration.html.in index e95ee9de6f..162c202227 100644 --- a/docs/migration.html.in +++ b/docs/migration.html.in @@ -201,6 +201,9 @@ numbers. In the latter case the management application may wish to choose a specific port number outside the default range in order to comply with local firewall policies. +
  • The second URI uses UNIX transport method. In this advanced case + libvirt should not guess a *migrateuri* and it should be specified using + UNIX socket path URI: unix:///path/to/socket.
  • Configuration file handling

    @@ -628,5 +631,35 @@ virsh migrate --p2p --tunnelled web1 qemu+ssh://desthost/system qemu+ssh://10.0. Supported by QEMU driver

    + +

    Migration using only UNIX sockets

    + +

    + In niche scenarios where libvirt daemon does not have access to the + network (e.g. running in a restricted container on a host that has + accessible network), when a management application wants to have complete + control over the transfer or when migrating between two containers on the + same host all the communication can be done using UNIX sockets. This + includes connecting to non-standard socket path for the destination + daemon, using UNIX sockets for hypervisor's communication or for the NBD + data transfer. All of that can be used with both peer2peer and direct + migration options. +

    + +

    + Example using /tmp/migdir as a directory representing the + same path visible from both libvirt daemons. That can be achieved by + bind-mounting the same directory to different containers running separate + daemons or forwarding connections to these sockets manually + (using socat, netcat or a custom piece of + software): +

    +virsh migrate web1 [--p2p] --copy-storage-all 'qemu+unix:///system?socket=/tmp/migdir/test-sock-driver' 'unix:///tmp/migdir/test-sock-qemu' --disks-uri unix:///tmp/migdir/test-sock-nbd
    +    
    + +

    + Supported by QEMU driver +

    + diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 80c56fec60..ce72e1021d 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -11480,7 +11480,7 @@ qemuDomainMigratePrepare3Params(virConnectPtr dconn, const char *dom_xml = NULL; const char *dname = NULL; const char *uri_in = NULL; - const char *listenAddress = cfg->migrationAddress; + const char *listenAddress = NULL; int nbdPort = 0; int nmigrate_disks; g_autofree const char **migrate_disks = NULL; @@ -11530,6 +11530,17 @@ qemuDomainMigratePrepare3Params(virConnectPtr dconn, return -1; } + if (listenAddress) { + if (uri_in && STRPREFIX(uri_in, "unix:")) { + virReportError(VIR_ERR_INVALID_ARG, "%s", + _("Usage of listen-address is forbidden when " + "migration URI uses UNIX transport method")); + return -1; + } + } else { + listenAddress = cfg->migrationAddress; + } + if (flags & VIR_MIGRATE_TUNNELLED) { /* this is a logical error; we never should have gotten here with * VIR_MIGRATE_TUNNELLED set @@ -11771,6 +11782,15 @@ qemuDomainMigratePerform3Params(virDomainPtr dom, goto cleanup; } + if (listenAddress) { + if (uri && STRPREFIX(uri, "unix:")) { + virReportError(VIR_ERR_INVALID_ARG, "%s", + _("Usage of listen-address is forbidden when " + "migration URI uses UNIX transport method")); + return -1; + } + } + nmigrate_disks = virTypedParamsGetStringList(params, nparams, VIR_MIGRATE_PARAM_MIGRATE_DISKS, &migrate_disks); diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c index f3870b3c0b..732e789c82 100644 --- a/src/qemu/qemu_migration.c +++ b/src/qemu/qemu_migration.c @@ -2411,6 +2411,8 @@ qemuMigrationDstPrepare(virDomainObjPtr vm, if (tunnel) { migrateFrom = g_strdup("stdio"); + } else if (g_strcmp0(protocol, "unix") == 0) { + migrateFrom = g_strdup_printf("%s:%s", protocol, listenAddress); } else { bool encloseAddress = false; bool hostIPv6Capable = false; @@ -2995,34 +2997,40 @@ qemuMigrationDstPrepareDirect(virQEMUDriverPtr driver, } if (STRNEQ(uri->scheme, "tcp") && - STRNEQ(uri->scheme, "rdma")) { + STRNEQ(uri->scheme, "rdma") && + STRNEQ(uri->scheme, "unix")) { virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, _("unsupported scheme %s in migration URI %s"), uri->scheme, uri_in); goto cleanup; } - if (uri->server == NULL) { - virReportError(VIR_ERR_INVALID_ARG, _("missing host in migration" - " URI: %s"), uri_in); - goto cleanup; - } - - if (uri->port == 0) { - if (virPortAllocatorAcquire(driver->migrationPorts, &port) < 0) - goto cleanup; - - /* Send well-formed URI only if uri_in was well-formed */ - if (well_formed_uri) { - uri->port = port; - if (!(*uri_out = virURIFormat(uri))) - goto cleanup; - } else { - *uri_out = g_strdup_printf("%s:%d", uri_in, port); - } - } else { - port = uri->port; + if (STREQ(uri->scheme, "unix")) { autoPort = false; + listenAddress = uri->path; + } else { + if (uri->server == NULL) { + virReportError(VIR_ERR_INVALID_ARG, _("missing host in migration" + " URI: %s"), uri_in); + goto cleanup; + } + + if (uri->port == 0) { + if (virPortAllocatorAcquire(driver->migrationPorts, &port) < 0) + goto cleanup; + + /* Send well-formed URI only if uri_in was well-formed */ + if (well_formed_uri) { + uri->port = port; + if (!(*uri_out = virURIFormat(uri))) + goto cleanup; + } else { + *uri_out = g_strdup_printf("%s:%d", uri_in, port); + } + } else { + port = uri->port; + autoPort = false; + } } } @@ -3237,6 +3245,8 @@ qemuMigrationSrcConfirm(virQEMUDriverPtr driver, enum qemuMigrationDestinationType { MIGRATION_DEST_HOST, MIGRATION_DEST_CONNECT_HOST, + MIGRATION_DEST_SOCKET, + MIGRATION_DEST_CONNECT_SOCKET, MIGRATION_DEST_FD, }; @@ -3256,6 +3266,10 @@ struct _qemuMigrationSpec { int port; } host; + struct { + const char *path; + } socket; + struct { int qemu; int local; @@ -3470,13 +3484,30 @@ qemuMigrationSrcConnect(virQEMUDriverPtr driver, if (qemuSecuritySetSocketLabel(driver->securityManager, vm->def) < 0) goto cleanup; - port = g_strdup_printf("%d", spec->dest.host.port); - if (virNetSocketNewConnectTCP(spec->dest.host.name, - port, - AF_UNSPEC, - &sock) == 0) { - fd_qemu = virNetSocketDupFD(sock, true); - virObjectUnref(sock); + + switch (spec->destType) { + case MIGRATION_DEST_CONNECT_HOST: + port = g_strdup_printf("%d", spec->dest.host.port); + if (virNetSocketNewConnectTCP(spec->dest.host.name, + port, + AF_UNSPEC, + &sock) == 0) { + fd_qemu = virNetSocketDupFD(sock, true); + virObjectUnref(sock); + } + break; + case MIGRATION_DEST_CONNECT_SOCKET: + if (virNetSocketNewConnectUNIX(spec->dest.socket.path, + false, NULL, + &sock) == 0) { + fd_qemu = virNetSocketDupFD(sock, true); + virObjectUnref(sock); + } + break; + case MIGRATION_DEST_HOST: + case MIGRATION_DEST_SOCKET: + case MIGRATION_DEST_FD: + break; } spec->destType = MIGRATION_DEST_FD; @@ -3684,6 +3715,13 @@ qemuMigrationSrcRun(virQEMUDriverPtr driver, if (migrate_flags & (QEMU_MONITOR_MIGRATE_NON_SHARED_DISK | QEMU_MONITOR_MIGRATE_NON_SHARED_INC)) { if (mig->nbd) { + const char *host = ""; + + if (spec->destType == MIGRATION_DEST_HOST || + spec->destType == MIGRATION_DEST_CONNECT_HOST) { + host = spec->dest.host.name; + } + /* Currently libvirt does not support setting up of the NBD * non-shared storage migration with TLS. As we need to honour the * VIR_MIGRATE_TLS flag, we need to reject such migration until @@ -3697,7 +3735,7 @@ qemuMigrationSrcRun(virQEMUDriverPtr driver, /* This will update migrate_flags on success */ if (qemuMigrationSrcNBDStorageCopy(driver, vm, mig, - spec->dest.host.name, + host, migrate_speed, &migrate_flags, nmigrate_disks, @@ -3745,7 +3783,8 @@ qemuMigrationSrcRun(virQEMUDriverPtr driver, goto exit_monitor; /* connect to the destination qemu if needed */ - if (spec->destType == MIGRATION_DEST_CONNECT_HOST && + if ((spec->destType == MIGRATION_DEST_CONNECT_HOST || + spec->destType == MIGRATION_DEST_CONNECT_SOCKET) && qemuMigrationSrcConnect(driver, vm, spec) < 0) { goto exit_monitor; } @@ -3767,7 +3806,14 @@ qemuMigrationSrcRun(virQEMUDriverPtr driver, spec->dest.host.port); break; + case MIGRATION_DEST_SOCKET: + qemuSecurityDomainSetPathLabel(driver, vm, spec->dest.socket.path, false); + rc = qemuMonitorMigrateToSocket(priv->mon, migrate_flags, + spec->dest.socket.path); + break; + case MIGRATION_DEST_CONNECT_HOST: + case MIGRATION_DEST_CONNECT_SOCKET: /* handled above and transformed into MIGRATION_DEST_FD */ break; @@ -3983,16 +4029,35 @@ qemuMigrationSrcPerformNative(virQEMUDriverPtr driver, } } - /* RDMA and multi-fd migration requires QEMU to connect to the destination - * itself. - */ - if (STREQ(uribits->scheme, "rdma") || (flags & VIR_MIGRATE_PARALLEL)) - spec.destType = MIGRATION_DEST_HOST; - else - spec.destType = MIGRATION_DEST_CONNECT_HOST; - spec.dest.host.protocol = uribits->scheme; - spec.dest.host.name = uribits->server; - spec.dest.host.port = uribits->port; + if (STREQ(uribits->scheme, "unix")) { + if ((flags & VIR_MIGRATE_TLS) && + !qemuMigrationParamsTLSHostnameIsSet(migParams)) { + virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s", + _("Explicit destination hostname is required " + "for TLS migration over UNIX socket")); + return -1; + } + + if (flags & VIR_MIGRATE_PARALLEL) + spec.destType = MIGRATION_DEST_SOCKET; + else + spec.destType = MIGRATION_DEST_CONNECT_SOCKET; + + spec.dest.socket.path = uribits->path; + } else { + /* RDMA and multi-fd migration requires QEMU to connect to the destination + * itself. + */ + if (STREQ(uribits->scheme, "rdma") || (flags & VIR_MIGRATE_PARALLEL)) + spec.destType = MIGRATION_DEST_HOST; + else + spec.destType = MIGRATION_DEST_CONNECT_HOST; + + spec.dest.host.protocol = uribits->scheme; + spec.dest.host.name = uribits->server; + spec.dest.host.port = uribits->port; + } + spec.fwdType = MIGRATION_FWD_DIRECT; ret = qemuMigrationSrcRun(driver, vm, persist_xml, cookiein, cookieinlen, cookieout, diff --git a/src/qemu/qemu_migration_params.c b/src/qemu/qemu_migration_params.c index 231a8a2ee8..5fde915963 100644 --- a/src/qemu/qemu_migration_params.c +++ b/src/qemu/qemu_migration_params.c @@ -1008,6 +1008,15 @@ qemuMigrationParamsDisableTLS(virDomainObjPtr vm, } +bool +qemuMigrationParamsTLSHostnameIsSet(qemuMigrationParamsPtr migParams) +{ + int param = QEMU_MIGRATION_PARAM_TLS_HOSTNAME; + return (migParams->params[param].set && + STRNEQ(migParams->params[param].value.s, "")); +} + + /* qemuMigrationParamsResetTLS * @driver: pointer to qemu driver * @vm: domain object diff --git a/src/qemu/qemu_migration_params.h b/src/qemu/qemu_migration_params.h index 9aea24725f..9876101bfc 100644 --- a/src/qemu/qemu_migration_params.h +++ b/src/qemu/qemu_migration_params.h @@ -113,6 +113,9 @@ int qemuMigrationParamsDisableTLS(virDomainObjPtr vm, qemuMigrationParamsPtr migParams); +bool +qemuMigrationParamsTLSHostnameIsSet(qemuMigrationParamsPtr migParams); + int qemuMigrationParamsFetch(virQEMUDriverPtr driver, virDomainObjPtr vm, diff --git a/src/qemu/qemu_monitor.c b/src/qemu/qemu_monitor.c index 718ac50c08..ab3bcc761e 100644 --- a/src/qemu/qemu_monitor.c +++ b/src/qemu/qemu_monitor.c @@ -2555,6 +2555,21 @@ qemuMonitorMigrateToHost(qemuMonitorPtr mon, } +int +qemuMonitorMigrateToSocket(qemuMonitorPtr mon, + unsigned int flags, + const char *socketPath) +{ + g_autofree char *uri = g_strdup_printf("unix:%s", socketPath); + + VIR_DEBUG("socketPath=%s flags=0x%x", socketPath, flags); + + QEMU_CHECK_MONITOR(mon); + + return qemuMonitorJSONMigrate(mon, flags, uri); +} + + int qemuMonitorMigrateCancel(qemuMonitorPtr mon) { diff --git a/src/qemu/qemu_monitor.h b/src/qemu/qemu_monitor.h index d20a15c202..3e4ef7e821 100644 --- a/src/qemu/qemu_monitor.h +++ b/src/qemu/qemu_monitor.h @@ -853,6 +853,10 @@ int qemuMonitorMigrateToHost(qemuMonitorPtr mon, const char *hostname, int port); +int qemuMonitorMigrateToSocket(qemuMonitorPtr mon, + unsigned int flags, + const char *socketPath); + int qemuMonitorMigrateCancel(qemuMonitorPtr mon); int qemuMonitorGetDumpGuestMemoryCapability(qemuMonitorPtr mon,