From c36bea1904bc34bf335e6f2bff50c05cb131df4c Mon Sep 17 00:00:00 2001
From: crimson <marco.tiloca@ri.se>
Date: Sat, 14 Sep 2024 10:26:46 +0200
Subject: [PATCH] Examples of non-AEAD algorithms as Group Encryption Algorithm

---
 draft-ietf-core-oscore-groupcomm.md | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/draft-ietf-core-oscore-groupcomm.md b/draft-ietf-core-oscore-groupcomm.md
index 32b7be7..52bdf1e 100644
--- a/draft-ietf-core-oscore-groupcomm.md
+++ b/draft-ietf-core-oscore-groupcomm.md
@@ -87,6 +87,7 @@ normative:
   RFC9053:
   RFC9175:
   RFC9338:
+  RFC9459:
   NIST-800-56A:
     author:
       -
@@ -131,6 +132,14 @@ informative:
   RFC8392:
   RFC9147:
   RFC9200:
+  ChaCha:
+    author:
+      -
+        ins: D. J. Bernstein
+        name: Daniel J. Bernstein
+    title: ChaCha, a variant of Salsa20
+    date: 2008-01
+    target: http://cr.yp.to/chacha/chacha-20080128.pdf
   Degabriele:
     author:
       -
@@ -324,6 +333,10 @@ The new parameter Group Manager Authentication Credential specifies the authenti
 
 The new parameter Group Encryption Algorithm identifies the algorithm to use for encryption and decryption, when messages are protected in group mode (see {{mess-processing}}). This algorithm MAY provide integrity protection. If this parameter is not set, the group mode is not used in the group.
 
+The following non-authenticated algorithms can be used as Group Encryption Algorithm: A128CBC, A192CBC, and A256CBC {{RFC9459}}. The non-authenticated algorithm ChaCha20 {{ChaCha}} is also suitable to consider, although using it will first require its registration in the "COSE Algorithms" Registry.
+
+The following non-authenticated algorithms MUST NOT be used as Group Encryption Algorithm: A128CTR, A192CTR, and A256CTR {{RFC9459}}.
+
 ### Signature Algorithm ## {#ssec-common-context-cs-alg}
 
 The new parameter Signature Algorithm identifies the digital signature algorithm used for computing and verifying the countersignature on the COSE object (see {{Sections 3.2 and 3.3 of RFC9338}}), when messages are protected in group mode (see {{mess-processing}}). If this parameter is not set, the group mode is not used in the group.