util: storage: Sanitize parsing of disk encryption XMLs

Pass in the XPath context as we do in all other places rather than
allocating a new one.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

src/conf/domain_conf.c

@@ -8542,7 +8542,8 @@ virDomainDiskSourceNetworkParse(xmlNodePtr node,
 
 static int
 virDomainDiskSourceEncryptionParse(xmlNodePtr node,
-                                   virStorageEncryptionPtr *encryptionsrc)
+                                   virStorageEncryptionPtr *encryptionsrc,
+                                   xmlXPathContextPtr ctxt)
 {
     xmlNodePtr child;
     virStorageEncryptionPtr encryption = NULL;
@@ -8551,7 +8552,7 @@ virDomainDiskSourceEncryptionParse(xmlNodePtr node,
         if (child->type == XML_ELEMENT_NODE &&
             virXMLNodeNameEqual(child, "encryption")) {
 
-            if (!(encryption = virStorageEncryptionParseNode(node->doc, child)))
+            if (!(encryption = virStorageEncryptionParseNode(child, ctxt)))
                 return -1;
 
             *encryptionsrc = encryption;
@@ -8637,7 +8638,7 @@ virDomainDiskSourceParse(xmlNodePtr node,
         !(src->auth = virStorageAuthDefParse(tmp, ctxt)))
         goto cleanup;
 
-    if (virDomainDiskSourceEncryptionParse(node, &src->encryption) < 0)
+    if (virDomainDiskSourceEncryptionParse(node, &src->encryption, ctxt) < 0)
         goto cleanup;
 
     if (virDomainDiskSourcePrivateDataParse(ctxt, src, flags, xmlopt) < 0)
@@ -9408,7 +9409,7 @@ virDomainDiskDefParseXML(virDomainXMLOptionPtr xmlopt,
                 goto error;
             }
 
-            if (!(encryption = virStorageEncryptionParseNode(node->doc, cur)))
+            if (!(encryption = virStorageEncryptionParseNode(cur, ctxt)))
                 goto error;
         } else if (!serial &&
                    virXMLNodeNameEqual(cur, "serial")) {

src/conf/storage_conf.c

@@ -1209,8 +1209,7 @@ virStorageVolDefParseXML(virStoragePoolDefPtr pool,
 
     node = virXPathNode("./target/encryption", ctxt);
     if (node != NULL) {
-        ret->target.encryption = virStorageEncryptionParseNode(ctxt->doc,
-                                                               node);
+        ret->target.encryption = virStorageEncryptionParseNode(node, ctxt);
         if (ret->target.encryption == NULL)
             goto error;
     }

src/util/virstorageencryption.c

@@ -242,9 +242,11 @@ virStorageEncryptionInfoParseIvgen(xmlNodePtr info_node,
 }
 
 
-static virStorageEncryptionPtr
-virStorageEncryptionParseXML(xmlXPathContextPtr ctxt)
+virStorageEncryptionPtr
+virStorageEncryptionParseNode(xmlNodePtr node,
+                              xmlXPathContextPtr ctxt)
 {
+    xmlNodePtr saveNode = ctxt->node;
     xmlNodePtr *nodes = NULL;
     virStorageEncryptionPtr encdef = NULL;
     virStorageEncryptionPtr ret = NULL;
@@ -252,6 +254,8 @@ virStorageEncryptionParseXML(xmlXPathContextPtr ctxt)
     int n;
     size_t i;
 
+    ctxt->node = node;
+
     if (VIR_ALLOC(encdef) < 0)
         goto cleanup;
 
@@ -311,34 +315,9 @@ virStorageEncryptionParseXML(xmlXPathContextPtr ctxt)
     VIR_FREE(format_str);
     VIR_FREE(nodes);
     virStorageEncryptionFree(encdef);
-    return ret;
-}
-
-virStorageEncryptionPtr
-virStorageEncryptionParseNode(xmlDocPtr xml, xmlNodePtr root)
-{
-    xmlXPathContextPtr ctxt = NULL;
-    virStorageEncryptionPtr enc = NULL;
-
-    if (STRNEQ((const char *) root->name, "encryption")) {
-        virReportError(VIR_ERR_XML_ERROR,
-                       "%s", _("unknown root element for volume "
-                               "encryption information"));
-        goto cleanup;
-    }
+    ctxt->node = saveNode;
 
-    ctxt = xmlXPathNewContext(xml);
-    if (ctxt == NULL) {
-        virReportOOMError();
-        goto cleanup;
-    }
-
-    ctxt->node = root;
-    enc = virStorageEncryptionParseXML(ctxt);
-
- cleanup:
-    xmlXPathFreeContext(ctxt);
-    return enc;
+    return ret;
 }
 
 

src/util/virstorageencryption.h

@@ -83,8 +83,8 @@ virStorageEncryptionPtr virStorageEncryptionCopy(const virStorageEncryption *src
 
 void virStorageEncryptionFree(virStorageEncryptionPtr enc);
 
-virStorageEncryptionPtr virStorageEncryptionParseNode(xmlDocPtr xml,
-                                                      xmlNodePtr root);
+virStorageEncryptionPtr virStorageEncryptionParseNode(xmlNodePtr node,
+                                                      xmlXPathContextPtr ctxt);
 int virStorageEncryptionFormat(virBufferPtr buf,
                                virStorageEncryptionPtr enc);