add const unsigned MaxMultipartNestingLevel = 100;

src/pEpMIME.hh

@@ -17,6 +17,14 @@
 namespace pEpMIME
 {
 
+// multipart messages are parsed recursively up to a maximum nesting level.
+// It should be large enough that all real-world mails can be parsed, but no
+// stack overflow occurs on maliciously crafted messages.
+// Deeper nested multipart messages are just put as attachment.
+// 100 seems to be a good default value, I think.
+const unsigned MaxMultipartNestingLevel = 100;
+
+
 // Parse the given string loosely as an "Internet Message" that aims to be RFC 5322
 // and MIME compliant (RFC 2046 etc.)
 //