From d103857c0f94c2ee40d6a41cd312d5e782331f7c Mon Sep 17 00:00:00 2001
From: Ben Kibbey <bjk@luxsci.net>
Date: Thu, 6 Dec 2007 19:03:21 -0500
Subject: [PATCH] Don't create any elements of an element path that contains an
 invalid element name.

---
 src/commands.c | 15 ++++++++++-----
 src/xml.c      | 44 ++++++++++++++++++++++++--------------------
 src/xml.h      |  1 +
 3 files changed, 35 insertions(+), 25 deletions(-)

diff --git a/src/commands.c b/src/commands.c
index b850fb69..50de7a78 100644
--- a/src/commands.c
+++ b/src/commands.c
@@ -1116,15 +1116,15 @@ static int store_command_finalize(gpointer data, gint rc, guchar *line,
     if (!req || !*req)
 	return EPWMD_COMMAND_SYNTAX;
 
+    if (valid_element_path(req, TRUE) == FALSE) {
+	g_strfreev(req);
+	return EPWMD_INVALID_ELEMENT;
+    }
+
 again:
     n = find_account(client->doc, &req, &error, NULL, 0);
 
     if (error && error == EPWMD_ELEMENT_NOT_FOUND) {
-	if (contains_whitespace(*req) == TRUE) {
-	    g_strfreev(req);
-	    return EPWMD_INVALID_ELEMENT;
-	}
-
 	error = new_account(client->doc, *req);
 
 	if (error) {
@@ -1956,6 +1956,11 @@ static gpg_error_t target_attribute(struct client_s *client, gchar **req)
 	    return EPWMD_COMMAND_SYNTAX;
     }
 
+    if (valid_element_path(src, FALSE) == FALSE) {
+	g_strfreev(src);
+	return EPWMD_INVALID_ELEMENT;
+    }
+
     if ((dst = split_input_line(req[1], "\t", 0)) == NULL) {
 	/*
 	 * The first argument may be only an account.
diff --git a/src/xml.c b/src/xml.c
index d2f9b862..3c9e06e8 100644
--- a/src/xml.c
+++ b/src/xml.c
@@ -71,8 +71,6 @@ gboolean is_literal_element(gchar **element)
 
 /*
  * Fails if 'element' begins with punctuation or digit or contains whitespace.
- * If the element is a literal element which was prefixed with '!', it should
- * be trimmed before calling this function.
  *
  * I'm not sure about using g_unichar_isspace() rather than isspace()?
  */
@@ -85,6 +83,9 @@ gboolean valid_xml_element(xmlChar *element)
     if (!element || !*element)
 	return FALSE;
 
+    if (*p == '!')
+	p++;
+
     len = g_utf8_strlen(p, -1) - 1;
     c = g_utf8_get_char(p++);
 
@@ -101,6 +102,25 @@ gboolean valid_xml_element(xmlChar *element)
     return TRUE;
 }
 
+gboolean valid_element_path(gchar **path, gboolean has_value)
+{
+    gchar **p;
+
+    for (p = path; *p; p++) {
+	/*
+	 * An empty element is valid and don't check the syntax of the
+	 * content.
+	 */
+	if (has_value == TRUE && (!*(p+1) || !*p[0]))
+	    break;
+
+	if (valid_xml_element((xmlChar *)*p) == FALSE)
+	    return FALSE;
+    }
+
+    return TRUE;
+}
+
 gpg_error_t new_account(xmlDocPtr doc, gchar *name)
 {
     xmlNodePtr root = xmlDocGetRootElement(doc);
@@ -114,13 +134,6 @@ gpg_error_t new_account(xmlDocPtr doc, gchar *name)
     if (is_literal_element_str(p))
 	p++;
 
-    /*
-     * Event though the account name is an attribute and not an element,
-     * element syntax still applies.
-     */
-    if (valid_xml_element((xmlChar *)p) == FALSE)
-	return EPWMD_INVALID_ELEMENT;
-
     n = xmlNewNode(NULL, (xmlChar *)"account");
     n = xmlAddChild(root, n);
     a = xmlNewProp(n, (xmlChar *)"name", (xmlChar *)p);
@@ -283,11 +296,6 @@ xmlNodePtr create_target_elements_cb(xmlNodePtr node, gchar **path,
     for (i = 0; req[i]; i++) {
 	xmlNodePtr n;
 
-	if (valid_xml_element((xmlChar *)req[i]) == FALSE) {
-	    *error = EPWMD_INVALID_ELEMENT;
-	    return NULL;
-	}
-
 	if ((n = find_element(node, req[i])) == NULL) {
 	    n = xmlNewNode(NULL, (xmlChar *)req[i]);
 
@@ -328,14 +336,10 @@ xmlNodePtr create_elements_cb(xmlNodePtr node, gchar **elements,
 	if (req[i+1]) {
 	    /*
 	     * Strip the first '!' if needed. If there's another, it's an
-	     * error.
+	     * error. The syntax has already been checked before calling this
+	     * function.
 	     */
 	    is_literal_element(&req[i]);
-
-	    if (valid_xml_element((xmlChar *)req[i]) == FALSE) {
-		*error = EPWMD_INVALID_ELEMENT;
-		return NULL;
-	    }
 	}
 
 	/*
diff --git a/src/xml.h b/src/xml.h
index a0894aa9..ccb6ff95 100644
--- a/src/xml.h
+++ b/src/xml.h
@@ -49,5 +49,6 @@ gboolean is_literal_element_str(gchar *element);
 xmlChar *node_has_attribute(xmlNodePtr n, xmlChar *attr);
 gboolean node_has_child_element(xmlNodePtr node);
 gint sort_element_list(gconstpointer a, gconstpointer b);
+gboolean valid_element_path(gchar **path, gboolean has_value);
 
 #endif
-- 
2.11.4.GIT