trying to fix #118754 of possible recursion in the catalogs. Not

* catalog.c: trying to fix #118754 of possible recursion in the
  catalogs. Not fantastically happy about the current fix since
  it's likely to break under very thread intensive concurrent
  access to the catalog. Better solution might to keep the depth
  an extra argument to the resolution functions.
Daniel

2 files changed, 40 insertions, 3 deletions

diff --git a/ChangeLog b/ChangeLog
index 0f064b03..a5f487ea 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+Sun Aug  3 20:55:40 EDT 2003 Daniel Veillard <daniel@veillard.com>
+
+	* catalog.c: trying to fix #118754 of possible recursion in the
+	  catalogs. Not fantastically happy about the current fix since
+	  it's likely to break under very thread intensive concurrent
+	  access to the catalog. Better solution might to keep the depth
+	  an extra argument to the resolution functions.
+
 Sun Aug  3 18:56:54 EDT 2003 Daniel Veillard <daniel@veillard.com>
 
 	* valid.c: fixed bug #118712 about mixed content, and namespaced
diff --git a/catalog.c b/catalog.c
index 06bffc66..d307bf4e 100644
--- a/catalog.c
+++ b/catalog.c
@@ -42,6 +42,7 @@
 #include <libxml/globals.h>
 
 #define MAX_DELEGATE	50
+#define MAX_CATAL_DEPTH	50
 
 /**
  * TODO:
@@ -115,6 +116,7 @@ struct _xmlCatalogEntry {
     xmlChar *URL;  /* The expanded URL using the base */
     xmlCatalogPrefer prefer;
     int dealloc;
+    int depth;
 };
 
 typedef enum {
@@ -230,6 +232,7 @@ xmlNewCatalogEntry(xmlCatalogEntryType type, const xmlChar *name,
 	ret->URL = NULL;
     ret->prefer = prefer;
     ret->dealloc = 0;
+    ret->depth = 0;
     return(ret);
 }
 
@@ -1443,6 +1446,20 @@ xmlCatalogXMLResolve(xmlCatalogEntryPtr catal, const xmlChar *pubID,
     int haveNext = 0;
 
     /*
+     * protection against loops
+     */
+    if (catal->depth > MAX_CATAL_DEPTH) {
+        if (catal->name != NULL)
+	    xmlGenericError(xmlGenericErrorContext,
+		    "Detected recursion in catalog %s\n", catal->name);
+	else
+	    xmlGenericError(xmlGenericErrorContext,
+		    "Detected recursion in catalog\n");
+	return(NULL);
+    }
+    catal->depth++;
+
+    /*
      * First tries steps 2/ 3/ 4/ if a system ID is provided.
      */
     if (sysID != NULL) {
@@ -1457,6 +1474,7 @@ xmlCatalogXMLResolve(xmlCatalogEntryPtr catal, const xmlChar *pubID,
 			if (xmlDebugCatalogs)
 			    xmlGenericError(xmlGenericErrorContext,
 				    "Found system match %s\n", cur->name);
+			catal->depth--;
 			return(xmlStrdup(cur->URL));
 		    }
 		    break;
@@ -1487,6 +1505,7 @@ xmlCatalogXMLResolve(xmlCatalogEntryPtr catal, const xmlChar *pubID,
 	    ret = xmlStrdup(rewrite->URL);
 	    if (ret != NULL)
 		ret = xmlStrcat(ret, &sysID[lenrewrite]);
+	    catal->depth--;
 	    return(ret);
 	}
 	if (haveDelegate) {
@@ -1520,8 +1539,10 @@ xmlCatalogXMLResolve(xmlCatalogEntryPtr catal, const xmlChar *pubID,
 				    "Trying system delegate %s\n", cur->URL);
 			ret = xmlCatalogListXMLResolve(
 				cur->children, NULL, sysID);
-			if (ret != NULL)
+			if (ret != NULL) {
+			    catal->depth--;
 			    return(ret);
+			}
 		    }
 		}
 		cur = cur->next;
@@ -1529,6 +1550,7 @@ xmlCatalogXMLResolve(xmlCatalogEntryPtr catal, const xmlChar *pubID,
 	    /*
 	     * Apply the cut algorithm explained in 4/
 	     */
+	    catal->depth--;
 	    return(XML_CATAL_BREAK);
 	}
     }
@@ -1545,6 +1567,7 @@ xmlCatalogXMLResolve(xmlCatalogEntryPtr catal, const xmlChar *pubID,
 			if (xmlDebugCatalogs)
 			    xmlGenericError(xmlGenericErrorContext,
 				    "Found public match %s\n", cur->name);
+			catal->depth--;
 			return(xmlStrdup(cur->URL));
 		    }
 		    break;
@@ -1595,8 +1618,10 @@ xmlCatalogXMLResolve(xmlCatalogEntryPtr catal, const xmlChar *pubID,
 				    "Trying public delegate %s\n", cur->URL);
 			ret = xmlCatalogListXMLResolve(
 				cur->children, pubID, NULL);
-			if (ret != NULL)
+			if (ret != NULL) {
+			    catal->depth--;
 			    return(ret);
+			}
 		    }
 		}
 		cur = cur->next;
@@ -1604,6 +1629,7 @@ xmlCatalogXMLResolve(xmlCatalogEntryPtr catal, const xmlChar *pubID,
 	    /*
 	     * Apply the cut algorithm explained in 4/
 	     */
+	    catal->depth--;
 	    return(XML_CATAL_BREAK);
 	}
     }
@@ -1616,14 +1642,17 @@ xmlCatalogXMLResolve(xmlCatalogEntryPtr catal, const xmlChar *pubID,
 		}
 		if (cur->children != NULL) {
 		    ret = xmlCatalogListXMLResolve(cur->children, pubID, sysID);
-		    if (ret != NULL)
+		    if (ret != NULL) {
+			catal->depth--;
 			return(ret);
+		    }
 		}
 	    }
 	    cur = cur->next;
 	}
     }
 
+    catal->depth--;
     return(NULL);
 }