XML: Tool function to extract relaystate from query

 * lasso/xml/tools.c, lasso/xml/private.h: new function
   lasso_get_relaystate_from_query to help in relaystate handling.

2 files changed, 32 insertions, 0 deletions

diff --git a/lasso/xml/private.h b/lasso/xml/private.h
index fe3da380..b13315e3 100644
--- a/lasso/xml/private.h
+++ b/lasso/xml/private.h
@@ -210,6 +210,8 @@ static inline void message(GLogLevelFlags level, const char *format, ...)
 	if (lasso_provider_get_protocol_conformance(LASSO_PROVIDER(profile->server)) == \
 			LASSO_PROTOCOL_SAML_2_0)
 
+char * lasso_get_relaystate_from_query(const char *query);
+
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */
diff --git a/lasso/xml/tools.c b/lasso/xml/tools.c
index 61c51a58..6f9ae73b 100644
--- a/lasso/xml/tools.c
+++ b/lasso/xml/tools.c
@@ -1464,3 +1464,33 @@ xmlDetectSAX2(xmlParserCtxtPtr ctxt) {
 		ctxt->errNo = XML_ERR_NO_MEMORY;
 	}
 }
+
+char *
+lasso_get_relaystate_from_query(const char *query) {
+	char *start, *end;
+	char *result = NULL;
+
+	if (query == NULL)
+		return NULL;
+	start = strstr(query, "?RelayState=");
+	if (! start) {
+		start = strstr(query, "&RelayState=");
+	}
+	if (start) {
+		ptrdiff_t length;
+
+		start += sizeof("&RelayState=") - 1;
+		end = strchr(start, '&');
+		if (end) {
+			length = end-start;
+		} else {
+			length = strlen(start);
+		}
+		if (length > 240) {
+			g_warning("Refused to parse a RelayState of size %ti > 240", length);
+		} else {
+			result = xmlURIUnescapeString(start, length, NULL);
+		}
+	}
+	return result;
+}