rsvp: add a comment about the INTEGRITY object structure.

The structure assumes a 16-byte digest, which is the case for HMAC-MD5,
but isn't necessarily the case for other hash algorithms.
Unfortunately, there's no obvious way to know what the authentication
algorithm is.

[skip ci]

diff --git a/print-rsvp.c b/print-rsvp.c
index 4254881dc45c6fc1ffebe627514b28d342b44239..ea6ccfd7cca434f24b2ecdee90e178b035548eb8 100644 (file)
--- a/print-rsvp.c
+++ b/print-rsvp.c
@@ -305,6 +305,14 @@ static const struct tok rsvp_ctype_values[] = {
     { 0, NULL}
 };
 
+/*
+ * XXX - this assumes a 16-byte digest, which is true for HMAC-MD5, but
+ * isn't necessarily the case for other hash algorithms.
+ *
+ * Unless I've missed something, there's nothing in RFC 2747 to indicate
+ * the hash algorithm being used, so it's presumably something set up
+ * out-of-band, or negotiated by other RSVP objects.
+ */
 struct rsvp_obj_integrity_t {
     uint8_t flags;
     uint8_t res;