Re: [libvirt PATCH v2 09/16] qemu: add functions to start and stop nbdkit

Add some helper functions to build a virCommand object and run the nbdkit process for a given virStorageSource. Signed-off-by: Jonathon Jongsma <jjongsma(a)redhat.com&gt; --- src/qemu/qemu_nbdkit.c | 208 +++++++++++++++++++++++++++++++++++++++++ src/qemu/qemu_nbdkit.h | 8 ++ 2 files changed, 216 insertions(+) diff --git a/src/qemu/qemu_nbdkit.c b/src/qemu/qemu_nbdkit.c index 4df8957196..e8f9acc17c 100644 --- a/src/qemu/qemu_nbdkit.c +++ b/src/qemu/qemu_nbdkit.c @@ -648,6 +648,156 @@ qemuNbdkitInitStorageSource(qemuNbdkitCaps *caps, } +static int +qemuNbdkitProcessBuildCommandCurl(qemuNbdkitProcess *proc, + virCommand *cmd) +{ + g_autoptr(virURI) uri = qemuBlockStorageSourceGetURI(proc->source); + g_autofree char *uristring = virURIFormat(uri); + + /* nbdkit plugin name */ + virCommandAddArg(cmd, "curl"); + virCommandAddArgPair(cmd, "protocols", + virStorageNetProtocolTypeToString(proc->source->protocol)); + virCommandAddArgPair(cmd, "url", uristring); + + if (proc->source->auth) { + g_autoptr(virConnect) conn = virGetConnectSecret(); + g_autofree uint8_t *secret = NULL; + size_t secretlen = 0; + g_autofree char *password = NULL; + int secrettype; + + virCommandAddArgPair(cmd, "user", + proc->source->auth->username); + + if ((secrettype = virSecretUsageTypeFromString(proc->source->auth->secrettype)) < 0) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + _("invalid secret type %s"), + proc->source->auth->secrettype); + return -1; + } + + if (virSecretGetSecretString(conn, + &proc->source->auth->seclookupdef, + secrettype, + &secret, + &secretlen) < 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("failed to get auth secret for storage")); + return -1; + } + + /* ensure that the secret is a NULL-terminated string */ + password = g_strndup((char*)secret, secretlen); + + virCommandAddArgPair(cmd, "password", password);

+ + virSecureErase(secret, secretlen); + virSecureErase(password, secretlen);

+ } + + if (proc->source->ncookies > 0) + virCommandAddArgPair(cmd, "cookie", + qemuBlockStorageSourceGetCookieString(proc->source));

+ + if (proc->source->sslverify == VIR_TRISTATE_BOOL_NO) { + virCommandAddArgPair(cmd, "sslverify", "false"); + } + + if (proc->source->timeout > 0) { + g_autofree char *timeout = g_strdup_printf("%llu", proc->source->timeout); + virCommandAddArgPair(cmd, "timeout", timeout); + } + + return 0; +} + + +static int +qemuNbdkitProcessBuildCommandSSH(qemuNbdkitProcess *proc, + virCommand *cmd) +{ + const char *user = NULL; + virStorageNetHostDef *host = &proc->source->hosts[0]; + g_autofree char *portstr = g_strdup_printf("%u", host->port); + + /* nbdkit plugin name */ + virCommandAddArg(cmd, "ssh"); + + virCommandAddArgPair(cmd, "host", host->name); + virCommandAddArgPair(cmd, "port", portstr); + virCommandAddArgPair(cmd, "path", proc->source->path); + + if (proc->source->auth) + user = proc->source->auth->username; + else if (proc->source->ssh_user) + user = proc->source->ssh_user; + + if (user) + virCommandAddArgPair(cmd, "user", user); + + if (proc->source->ssh_host_key_check_disabled) + virCommandAddArgPair(cmd, "verify-remote-host", "false");

+ + return 0; +} + + +static virCommand * +qemuNbdkitProcessBuildCommand(qemuNbdkitProcess *proc) +{ + g_autoptr(virCommand) cmd = virCommandNewArgList(proc->caps->path, + "--exit-with-parent", + "--unix", + proc->socketfile, + "--foreground", + //"--selinux-label", + //selinux_label, + NULL); + + if (proc->source->readonly) + virCommandAddArg(cmd, "--readonly"); + + if (qemuNbdkitCapsGet(proc->caps, QEMU_NBDKIT_CAPS_FILTER_READAHEAD) && + proc->source->readahead > 0) + virCommandAddArgPair(cmd, "--filter", "readahead");

+ + switch (proc->source->protocol) { + case VIR_STORAGE_NET_PROTOCOL_HTTP: + case VIR_STORAGE_NET_PROTOCOL_HTTPS: + case VIR_STORAGE_NET_PROTOCOL_FTP: + case VIR_STORAGE_NET_PROTOCOL_FTPS: + case VIR_STORAGE_NET_PROTOCOL_TFTP: + if (qemuNbdkitProcessBuildCommandCurl(proc, cmd) < 0) + return NULL; + break; + case VIR_STORAGE_NET_PROTOCOL_SSH: + if (qemuNbdkitProcessBuildCommandSSH(proc, cmd) < 0) + return NULL; + break; + + case VIR_STORAGE_NET_PROTOCOL_NONE: + case VIR_STORAGE_NET_PROTOCOL_NBD: + case VIR_STORAGE_NET_PROTOCOL_RBD: + case VIR_STORAGE_NET_PROTOCOL_SHEEPDOG: + case VIR_STORAGE_NET_PROTOCOL_GLUSTER: + case VIR_STORAGE_NET_PROTOCOL_ISCSI: + case VIR_STORAGE_NET_PROTOCOL_VXHS: + case VIR_STORAGE_NET_PROTOCOL_NFS: + case VIR_STORAGE_NET_PROTOCOL_LAST: + virReportError(VIR_ERR_NO_SUPPORT, + _("protocol '%s' is not supported by nbdkit"), + virStorageNetProtocolTypeToString(proc->source->protocol)); + return NULL; + } + + virCommandDaemonize(cmd); + + return g_steal_pointer(&cmd); +} + + void qemuNbdkitProcessFree(qemuNbdkitProcess *proc) { @@ -661,3 +811,61 @@ qemuNbdkitProcessFree(qemuNbdkitProcess *proc) g_clear_object(&proc->caps); g_free(proc); } + + +int +qemuNbdkitProcessStart(qemuNbdkitProcess *proc, + virDomainObj *vm, + virQEMUDriver *driver) +{ + g_autoptr(virCommand) cmd = NULL; + int rc; + int exitstatus = 0; + int cmdret = 0; + int errfd = -1; + + if (!(cmd = qemuNbdkitProcessBuildCommand(proc))) + return -1; + + virCommandSetErrorFD(cmd, &errfd); + virCommandSetPidFile(cmd, proc->pidfile); + + if (qemuExtDeviceLogCommand(driver, vm, cmd, "nbdkit") < 0) + goto error; + + if (qemuSecurityCommandRun(driver, vm, cmd, proc->user, proc->group, &exitstatus, &cmdret) < 0) + goto error; + + if (cmdret < 0 || exitstatus != 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Could not start 'nbdkit'. exitstatus: %d"), exitstatus); + goto error; + } + + if ((rc = virPidFileReadPath(proc->pidfile, &proc->pid)) < 0) { + virReportSystemError(-rc, + _("Failed to read pidfile %s"), + proc->pidfile); + goto error; + } + + return 0; + + error: + if (errfd > 0) { + char errbuf[1024] = { 0 };

+ if (read(errfd, errbuf, sizeof(errbuf) - 1) > 0) + VIR_WARN("nbdkit failed to start: %s", errbuf);

+ } + if (proc->pid) + virProcessKillPainfully(proc->pid, true); + unlink(proc->pidfile); + return -1; +}