Re: [libvirt] [PATCH v2 11/15] storage: Add support to create a luks volume

Partially resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1301021 If the volume xml was looking to create a luks volume take the necessary steps in order to make that happen. The processing will be: 1. create a temporary file in the storage driver state dir path 1a. the file name will include the pool name, the volume name, secret, and XXXXXX for usage in the mkostemp call. 1b. mkostemp the file, initially setting mode to 0600 with current effective uid:gid as owner 1c. fetch the secret into a buffer and write that into the file 1d. change file protections to 0400 2. create a secret object 2a. use an alias combinding the volume name and "_luks0" 2b. add the file to the object 3. create/add luks options to the commandline 3a. at the very least a "key-secret" using the secret object alias 3b. if found in the XML the various "cipher" and "ivgen" options Signed-off-by: John Ferlan <jferlan(a)redhat.com&gt; --- src/libvirt_private.syms | 1 + src/storage/storage_backend.c | 260 ++++++++++++++++++++++++++++++++++++++--- src/storage/storage_backend.h | 3 +- src/util/virqemu.c | 23 ++++ src/util/virqemu.h | 6 + tests/storagevolxml2argvtest.c | 3 +- 6 files changed, 275 insertions(+), 21 deletions(-)

@@ -1240,6 +1366,84 @@ virStorageBackendCreateQemuImgCmdFromVol(virConnectPtr conn, return cmd; } + +static char * +virStorageBackendCreateQemuImgSecretPath(virConnectPtr conn, + virStoragePoolObjPtr pool, + virStorageVolDefPtr vol) +{ + virStorageEncryptionPtr enc = vol->target.encryption; + char *secretPath = NULL; + int fd = -1; + uint8_t *secret = NULL; + size_t secretlen = 0; + + if (!enc) { + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("missing encryption description")); + return NULL; + } + + if (!conn || !conn->secretDriver || + !conn->secretDriver->secretLookupByUUID || + !conn->secretDriver->secretLookupByUsage || + !conn->secretDriver->secretGetValue) { + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("unable to look up encryption secret")); + return NULL; + } + + /* Since we don't have a file, just go to cleanup using NULL secretPath */ + if (!(secretPath = virStoragePoolObjBuildTempFilePath(pool, vol))) + goto cleanup; + + if ((fd = mkostemp(secretPath, O_CLOEXEC)) < 0) { + virReportSystemError(errno, "%s", + _("failed to open luks secret file for write")); + goto error; + } + + if (virSecretGetSecretString(conn, &enc->secrets[0]->seclookupdef, + VIR_SECRET_USAGE_TYPE_PASSPHRASE, + &secret, &secretlen) < 0) + goto error; + + if (safewrite(fd, secret, secretlen) < 0) { + virReportSystemError(errno, "%s", + _("failed to write luks secret file")); + goto error; + } + VIR_FORCE_CLOSE(fd); + + if ((vol->target.perms->uid != (uid_t) -1) && + (vol->target.perms->gid != (gid_t) -1)) { + if (chown(secretPath, vol->target.perms->uid,

+ vol->target.perms->gid) < 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("failed to chown luks secret file")); + goto error; + } + } + + if (chmod(secretPath, 0400) < 0) {

+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("failed to chown luks secret file")); + goto error; + } + + cleanup: + VIR_DISPOSE_N(secret, secretlen); + VIR_FORCE_CLOSE(fd); + + return secretPath; + + error: + unlink(secretPath); + VIR_FREE(secretPath); + goto cleanup; +} + + int virStorageBackendCreateQemuImg(virConnectPtr conn, virStoragePoolObjPtr pool,