tools: reimplement xmlURIEscapeStr to respect RFC3986 (#45581)

Bugfix by Emmanuel Dreyfus.

License: MIT

AUTHORS

@@ -21,6 +21,7 @@ Core
 	contributed under MIT license by XCG consulting
 - Simo Sorce <simo@redhat.com>, code review using Coverity and related
 	bugfixes, contributed under MIT license by Redhat Inc.
+- Emmanuel Dreyfus <manu@netbsd.org>, bug fixes, contributed under MIT license.
 
 Unit Tests
 ==========

lasso/id-ff/login.c

@@ -988,11 +988,11 @@ lasso_login_build_artifact_msg(LassoLogin *login, LassoHttpMethod http_method)
 	}
 
 	b64_samlArt = xmlStrdup((xmlChar*)login->assertionArtifact);
-	relayState = xmlURIEscapeStr(
+	relayState = lasso_xmlURIEscapeStr(
 			(xmlChar*)LASSO_LIB_AUTHN_REQUEST(profile->request)->RelayState, NULL);
 
 	if (http_method == LASSO_HTTP_METHOD_REDIRECT) {
-		xmlChar *escaped_artifact = xmlURIEscapeStr(b64_samlArt, NULL);
+		xmlChar *escaped_artifact = lasso_xmlURIEscapeStr(b64_samlArt, NULL);
 		gchar *query = NULL;
 
 		if (relayState == NULL) {

lasso/xml/private.h

@@ -287,6 +287,7 @@ gboolean lasso_eval_xpath_expression(xmlXPathContextPtr xpath_ctx, const char *e
 
 char * lasso_get_relaystate_from_query(const char *query);
 char * lasso_url_add_parameters(char *url, gboolean free, ...);
+xmlChar * lasso_xmlURIEscapeStr(const xmlChar *from, const xmlChar *list);
 xmlSecKey* lasso_xmlsec_load_private_key_from_buffer(const char *buffer, size_t length, const char *password, LassoSignatureMethod signature_method, const char *certificate);
 xmlSecKey* lasso_xmlsec_load_private_key(const char *filename_or_buffer, const char *password,
 		LassoSignatureMethod signature_method, const char *certificate);

lasso/xml/tools.c

@@ -36,6 +36,7 @@
 #define _BSD_SOURCE
 #include "private.h"
 #include <string.h>
+#include <strings.h>
 #include <time.h>
 #include <ctype.h>
 #include <stdarg.h>
@@ -540,7 +541,7 @@ lasso_query_sign(char *query, LassoSignatureContext context)
 	}
 
 	{
-		const char *t = (char*)xmlURIEscapeStr(algo_href, NULL);
+		const char *t = (char*)lasso_xmlURIEscapeStr(algo_href, NULL);
 		new_query = g_strdup_printf("%s&SigAlg=%s", query, t);
 		xmlFree(BAD_CAST t);
 	}
@@ -662,7 +663,7 @@ lasso_query_sign(char *query, LassoSignatureContext context)
 	/* Base64 encode the signature value */
 	b64_sigret = xmlSecBase64Encode(sigret, sigret_size, 0);
 	/* escape b64_sigret */
-	e_b64_sigret = xmlURIEscapeStr((xmlChar*)b64_sigret, NULL);
+	e_b64_sigret = lasso_xmlURIEscapeStr((xmlChar*)b64_sigret, NULL);
 
 	/* add signature */
 	switch (sign_method) {
@@ -1307,7 +1308,7 @@ lasso_xmlnode_build_deflated_query(xmlNode *xmlnode)
 	b64_ret = xmlSecBase64Encode(ret, stream.total_out, 0);
 	lasso_release(ret);
 
-	ret = xmlURIEscapeStr(b64_ret, NULL);
+	ret = lasso_xmlURIEscapeStr(b64_ret, NULL);
 	rret = g_strdup((char*)ret);
 	xmlFree(b64_ret);
 	xmlFree(ret);
@@ -2329,7 +2330,7 @@ lasso_url_add_parameters(char *url,
 		if (! key) {
 			break;
 		}
-		encoded_key = xmlURIEscapeStr((xmlChar*)key, NULL);
+		encoded_key = lasso_xmlURIEscapeStr((xmlChar*)key, NULL);
 		goto_cleanup_if_fail(encoded_key);
 
 		value = va_arg(ap, char*);
@@ -2337,7 +2338,7 @@ lasso_url_add_parameters(char *url,
 			message(G_LOG_LEVEL_CRITICAL, "lasso_url_add_parameter: key without a value !!");
 			break;
 		}
-		encoded_value = xmlURIEscapeStr((xmlChar*)value, NULL);
+		encoded_value = lasso_xmlURIEscapeStr((xmlChar*)value, NULL);
 		goto_cleanup_if_fail(encoded_value);
 
 		if (old_url) {
@@ -2480,6 +2481,56 @@ lasso_base64_decode(const char *from, char **buffer, int *buffer_len)
 	return TRUE;
 }
 
+/**
+ * lasso_xmlURIEscapeStr:
+ * @from: the source URI string
+ * @list: optional list of characters not to escape
+ *
+ * Drop-in replacement for libxml2 xmlURIEscapeStr(), but encoding
+ * everything but [A-Za-z0-9._~-] which are the unreserved chartacters
+ * for RFC3986 section 2.3
+ *
+ * Return value: a buffer containing the URL-encoded string or NULL on error
+ */
+xmlChar *
+lasso_xmlURIEscapeStr(const xmlChar *from, const xmlChar *list)
+{
+	size_t len = 0;
+	const xmlChar *fp;
+	xmlChar *result;
+	int ri;
+
+	if (list == NULL)
+		list = "";
+
+	for (fp = from; *fp; fp++) {
+		if (isalnum(*fp) || index("._~-", *fp) || index(list, *fp))
+			len++;
+		else
+			len += 3;
+	}
+
+	result = g_malloc0(len + 1);
+	ri = 0;
+
+	for (fp = from; *fp; fp++) {
+		if (isalnum(*fp) || index("._~-", *fp) || index(list, *fp)) {
+			result[ri++] = *fp;
+		} else {
+			int msb = (*fp & 0xf0) >> 4;
+			int lsb = *fp & 0x0f;
+
+			result[ri++] = '%';
+			result[ri++] = (msb > 9) ? 'A' + msb - 10 : '0' + msb;
+			result[ri++] = (lsb > 9) ? 'A' + lsb - 10 : '0' + lsb;
+		}
+	}
+
+	result[ri++] = '\0';
+
+	return result;
+}
+
 /**
  * lasso_xmlsec_load_private_key_from_buffer:
  * @buffer: a buffer containing a key in any format

lasso/xml/xml.c

@@ -3120,7 +3120,7 @@ get_value_by_path(LassoNode *node, char *path, struct XmlSnippet *xml_snippet)
 				s = xmlGetProp(t, a->name);
 				g_string_append(result, a->name);
 				g_string_append(result, "=");
-				s2 = xmlURIEscapeStr(s, NULL);
+				s2 = lasso_xmlURIEscapeStr(s, NULL);
 				g_string_append(result, s2);
 				xmlFree(s2);
 				xmlFree(s);
@@ -3140,7 +3140,7 @@ get_value_by_path(LassoNode *node, char *path, struct XmlSnippet *xml_snippet)
 				g_string_append(result, (char*)c->name);
 				g_string_append(result, "=");
 				s = xmlNodeGetContent(c);
-				s2 = xmlURIEscapeStr(s, NULL);
+				s2 = lasso_xmlURIEscapeStr(s, NULL);
 				g_string_append(result, (char*)s2);
 				xmlFree(s2);
 				xmlFree(s);
@@ -3263,7 +3263,7 @@ lasso_node_build_query_from_snippets(LassoNode *node)
 				g_string_append(s, "&");
 			g_string_append(s, field_name);
 			g_string_append(s, "=");
-			t = xmlURIEscapeStr((xmlChar*)v, NULL);
+			t = lasso_xmlURIEscapeStr((xmlChar*)v, NULL);
 			g_string_append(s, (char*)t);
 			xmlFree(t);
 		}
@@ -3634,7 +3634,7 @@ lasso_node_export_to_saml2_query(LassoNode *node, const char *param_name, const
 	value = lasso_node_build_deflated_query(node);
 	if (! value)
 		goto cleanup;
-	encoded_param = xmlURIEscapeStr(BAD_CAST param_name, NULL);
+	encoded_param = lasso_xmlURIEscapeStr(BAD_CAST param_name, NULL);
 	if (! encoded_param)
 		goto cleanup;
 	query = g_strdup_printf("%s=%s", encoded_param, value);