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Date:      Sun, 23 Oct 2011 16:47:38 GMT
From:      Ryan Steinmetz <zi@FreeBSD.org>
To:        freebsd-gnats-submit@FreeBSD.org
Subject:   bin/161936: [openbsm][patch] praudit can produce invalid XML output
Message-ID:  <201110231647.p9NGlcm9029317@red.freebsd.org>
Resent-Message-ID: <201110231650.p9NGo3lG017129@freefall.freebsd.org>

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>Number:         161936
>Category:       bin
>Synopsis:       [openbsm][patch] praudit can produce invalid XML output
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sun Oct 23 16:50:03 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Ryan Steinmetz
>Release:        8.2-RELEASE
>Organization:
Rochester Institute of Technology
>Environment:
>Description:
When using praudit to display audit entries, the XML output argument (-x) will cause praudit to print invalid XML in certain circumstances.

This surfaces anytime a command is audited that contains invalid XML characters (& or <).
>How-To-Repeat:
Ensure command logging is enabled and execute a command like the following:
% echo hi < test && ls
% praudit -x >file.tmp

Then use an XML parser to try to parse file.tmp, it will complain about invalid characters due to the presence of & and < in places they should not be.
>Fix:
Applying the attached patch to contrib/openbsm/libbsm/bsm_io.c properly sanitizes the entries as they are printed by replacing instances of & with &amp; and < with &lt;

cd /usr/src
patch < /path/to/bsm_io.c.diff
cd lib/libbsm && make clean;make obj && make depend && make && make install

Patch attached with submission follows:

--- contrib/openbsm/libbsm/bsm_io.c.orig	2011-10-23 12:10:40.000000000 -0400
+++ contrib/openbsm/libbsm/bsm_io.c	2011-10-23 12:35:31.000000000 -0400
@@ -214,6 +214,28 @@
 }
 
 /*
+ * Prints the given data bytes as an XML-sanitized string
+ */
+static void
+print_xml_string(FILE *fp, const char *str, size_t len)
+{
+	u_int32_t i;
+
+	if (len > 0) {
+		for (i = 0; i < len; i++) {
+			if (str[i] != '\0') {
+				if (str[i] == '&')
+					fprintf(fp, "&amp;");
+				else if (str[i] == '<')
+					fprintf(fp, "&lt;");
+				else
+					fprintf(fp, "%c", str[i]);
+			}
+		}
+	}
+}
+
+/*
  * Prints the beggining of attribute.
  */
 static void
@@ -1855,7 +1877,7 @@
 	for (i = 0; i < tok->tt.execarg.count; i++) {
 		if (xml) {
 			fprintf(fp, "<arg>");
-			print_string(fp, tok->tt.execarg.text[i],
+			print_xml_string(fp, tok->tt.execarg.text[i],
 			    strlen(tok->tt.execarg.text[i]));
 			fprintf(fp, "</arg>");
 		} else {
@@ -1914,7 +1936,7 @@
 	for (i = 0; i< tok->tt.execenv.count; i++) {
 		if (xml) {
 			fprintf(fp, "<env>");
-			print_string(fp, tok->tt.execenv.text[i],
+			print_xml_string(fp, tok->tt.execenv.text[i],
 			    strlen(tok->tt.execenv.text[i]));
 			fprintf(fp, "</env>");
 		} else {


>Release-Note:
>Audit-Trail:
>Unformatted:



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