encryption: Add luks parsing for storageencryption

Add parse and format of the luks/passphrase secret including tests for
volume XML parsing.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

docs/formatsecret.html.in

@@ -248,7 +248,12 @@
     <p>
       This secret is a general purpose secret to be used by various libvirt
       objects to provide a single passphrase as required by the object in
-      order to perform its authentication.
+      order to perform its authentication. For example, this secret will
+      be used either by the
+      <a href="formatstorage.html#StorageVol">storage volume</a> in order to
+      provide the passphrase to encrypt a luks volume or by the
+      <a href="formatdomain.html#elementsDisks">disk device</a> in order to
+      provide the passphrase to decrypt the luks volume for usage.
       <span class="since">Since 2.1.0</span>. The following is an example
       of a secret.xml file:
     </p>

docs/formatstorageencryption.html.in

@@ -56,8 +56,20 @@
       the <code>secret</code> element is not present during volume creation,
       a secret is automatically generated and attached to the volume.
     </p>
+    <h3><a name="StorageEncryptionLuks">"luks" format</a></h3>
+    <p>
+      The <code>luks</code> format is specific to a luks encrypted volume
+      and the secret used in order to either encrypt or decrypt the volume.
+      A single <code>&lt;secret type='passphrase'...&gt;</code> element is
+      expected. The secret may be referenced via either a <code>uuid</code> or
+      <code>usage</code> attribute. One of the two must be present. When
+      present for volume creation, the secret will be used in order for
+      volume encryption.  When present for domain usage, the secret will
+      be used as the passphrase to decrypt the volume.
+      <span class="since">Since 2.1.0</span>.
+    </p>
 
-    <h2><a name="example">Example</a></h2>
+    <h2><a name="example">Examples</a></h2>
 
     <p>
       Here is a simple example, specifying use of the <code>qcow</code> format:
@@ -67,5 +79,17 @@
       &lt;encryption format='qcow'&gt;
          &lt;secret type='passphrase' uuid='c1f11a6d-8c5d-4a3e-ac7a-4e171c5e0d4a' /&gt;
       &lt;/encryption&gt;</pre>
+
+    <p>
+      Here is a simple example, specifying use of the <code>luks</code> format
+      where it's assumed that a <code>secret</code> has been defined using a
+      <code>usage</code> element with a <code>id</code> of "luks_example":
+    </p>
+    <pre>
+      &lt;encryption format='luks'&gt;
+         &lt;secret type='passphrase' usage='luks_example'/&gt;
+      &lt;/encryption&gt;
+    </pre>
+
   </body>
 </html>

docs/schemas/storagecommon.rng

@@ -12,6 +12,7 @@
         <choice>
           <value>default</value>
           <value>qcow</value>
+          <value>luks</value>
         </choice>
       </attribute>
       <zeroOrMore>
@@ -81,6 +82,7 @@
       <value>fat</value>
       <value>vhd</value>
       <value>ploop</value>
+      <value>luks</value>
       <ref name='storageFormatBacking'/>
     </choice>
   </define>

src/qemu/qemu_process.c

@@ -2414,6 +2414,12 @@ qemuProcessInitPasswords(virConnectPtr conn,
             !virDomainDiskGetSource(vm->def->disks[i]))
             continue;
 
+        if (vm->def->disks[i]->src->encryption->format !=
+            VIR_STORAGE_ENCRYPTION_FORMAT_DEFAULT &&
+            vm->def->disks[i]->src->encryption->format !=
+            VIR_STORAGE_ENCRYPTION_FORMAT_QCOW)
+            continue;
+
         VIR_FREE(secret);
         if (qemuProcessGetVolumeQcowPassphrase(conn,
                                                vm->def->disks[i],

src/storage/storage_backend.c

@@ -1027,8 +1027,7 @@ virStorageBackendCreateQemuImgCheckEncryption(int format,
         }
     } else {
         virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
-                       _("qcow volume encryption unsupported with "
-                         "volume format %s"), type);
+                       _("volume encryption unsupported with format %s"), type);
         return -1;
     }
 

src/storage/storage_backend_fs.c

@@ -157,7 +157,12 @@ virStorageBackendProbeTarget(virStorageSourcePtr target,
         case VIR_STORAGE_FILE_QCOW2:
             (*encryption)->format = VIR_STORAGE_ENCRYPTION_FORMAT_QCOW;
             break;
-        default:
+
+        case VIR_STORAGE_FILE_LUKS:
+            (*encryption)->format = VIR_STORAGE_ENCRYPTION_FORMAT_LUKS;
+            break;
+
+        case VIR_STORAGE_ENCRYPTION_FORMAT_LAST:
             break;
         }
 

src/storage/storage_backend_gluster.c

@@ -321,6 +321,8 @@ virStorageBackendGlusterRefreshVol(virStorageBackendGlusterStatePtr state,
         if (vol->target.format == VIR_STORAGE_FILE_QCOW ||
             vol->target.format == VIR_STORAGE_FILE_QCOW2)
             vol->target.encryption->format = VIR_STORAGE_ENCRYPTION_FORMAT_QCOW;
+        if (vol->target.format == VIR_STORAGE_FILE_LUKS)
+            vol->target.encryption->format = VIR_STORAGE_ENCRYPTION_FORMAT_LUKS;
     }
     vol->target.features = meta->features;
     meta->features = NULL;

src/util/virstorageencryption.c

@@ -43,7 +43,7 @@ VIR_ENUM_IMPL(virStorageEncryptionSecret,
 
 VIR_ENUM_IMPL(virStorageEncryptionFormat,
               VIR_STORAGE_ENCRYPTION_FORMAT_LAST,
-              "default", "qcow")
+              "default", "qcow", "luks")
 
 static void
 virStorageEncryptionSecretFree(virStorageEncryptionSecretPtr secret)

src/util/virstorageencryption.h

@@ -48,6 +48,7 @@ typedef enum {
     /* "default" is only valid for volume creation */
     VIR_STORAGE_ENCRYPTION_FORMAT_DEFAULT = 0,
     VIR_STORAGE_ENCRYPTION_FORMAT_QCOW, /* Both qcow and qcow2 */
+    VIR_STORAGE_ENCRYPTION_FORMAT_LUKS,
 
     VIR_STORAGE_ENCRYPTION_FORMAT_LAST,
 } virStorageEncryptionFormatType;

tests/qemuxml2argvdata/qemuxml2argv-luks-disks.xml

+<domain type='qemu'>
+  <name>encryptdisk</name>
+  <uuid>496898a6-e6ff-f7c8-5dc2-3cf410945ee9</uuid>
+  <memory unit='KiB'>1048576</memory>
+  <currentMemory unit='KiB'>524288</currentMemory>
+  <vcpu placement='static'>1</vcpu>
+  <os>
+    <type arch='x86_64' machine='pc-i440fx-2.1'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu</emulator>
+    <disk type='file' device='disk'>
+      <driver name='qemu' type='luks'/>
+      <source file='/storage/guest_disks/encryptdisk'/>
+      <target dev='vda' bus='virtio'/>
+      <encryption format='luks'>
+        <secret type='passphrase' uuid='0a81f5b2-8403-7b23-c8d6-21ccc2f80d6f'/>
+      </encryption>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
+    </disk>
+    <disk type='file' device='disk'>
+      <driver name='qemu' type='luks'/>
+      <source file='/storage/guest_disks/encryptdisk2'/>
+      <target dev='vdb' bus='virtio'/>
+      <encryption format='luks'>
+        <secret type='passphrase' usage='mycluster_myname'/>
+      </encryption>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
+    </disk>
+    <controller type='usb' index='0'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
+    </controller>
+    <controller type='pci' index='0' model='pci-root'/>
+    <input type='mouse' bus='ps2'/>
+    <input type='keyboard' bus='ps2'/>
+    <memballoon model='virtio'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
+    </memballoon>
+  </devices>
+</domain>

tests/qemuxml2xmloutdata/qemuxml2xmlout-luks-disks.xml

+../qemuxml2argvdata/qemuxml2argv-luks-disks.xml
\ No newline at end of file

tests/qemuxml2xmltest.c

@@ -502,6 +502,7 @@ mymain(void)
 
     DO_TEST("encrypted-disk");
     DO_TEST("encrypted-disk-usage");
+    DO_TEST("luks-disks");
     DO_TEST("memtune");
     DO_TEST("memtune-unlimited");
     DO_TEST("blkiotune");

tests/storagevolxml2xmlin/vol-luks.xml

+<volume>
+  <name>LuksDemo.img</name>
+  <key>/var/lib/libvirt/images/LuksDemo.img</key>
+  <source>
+  </source>
+  <capacity unit="G">5</capacity>
+  <allocation>294912</allocation>
+  <target>
+    <path>/var/lib/libvirt/images/LuksDemo.img</path>
+    <format type='luks'/>
+    <permissions>
+      <mode>0644</mode>
+      <owner>0</owner>
+      <group>0</group>
+      <label>unconfined_u:object_r:virt_image_t:s0</label>
+    </permissions>
+    <encryption format='luks'>
+      <secret type='passphrase' usage='mumblyfratz'/>
+    </encryption>
+  </target>
+</volume>

tests/storagevolxml2xmlout/vol-luks.xml

+<volume type='file'>
+  <name>LuksDemo.img</name>
+  <key>/var/lib/libvirt/images/LuksDemo.img</key>
+  <source>
+  </source>
+  <capacity unit='bytes'>5368709120</capacity>
+  <allocation unit='bytes'>294912</allocation>
+  <target>
+    <path>/var/lib/libvirt/images/LuksDemo.img</path>
+    <format type='luks'/>
+    <permissions>
+      <mode>0644</mode>
+      <owner>0</owner>
+      <group>0</group>
+      <label>unconfined_u:object_r:virt_image_t:s0</label>
+    </permissions>
+    <encryption format='luks'>
+      <secret type='passphrase' usage='mumblyfratz'/>
+    </encryption>
+  </target>
+</volume>

tests/storagevolxml2xmltest.c

@@ -105,6 +105,7 @@ mymain(void)
     DO_TEST("pool-dir", "vol-qcow2-lazy");
     DO_TEST("pool-dir", "vol-qcow2-0.10-lazy");
     DO_TEST("pool-dir", "vol-qcow2-nobacking");
+    DO_TEST("pool-dir", "vol-luks");
     DO_TEST("pool-disk", "vol-partition");
     DO_TEST("pool-logical", "vol-logical");
     DO_TEST("pool-logical", "vol-logical-backing");