===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/ssh/PROTOCOL,v
retrieving revision 1.50
retrieving revision 1.51
diff -u -r1.50 -r1.51
--- src/usr.bin/ssh/PROTOCOL	2023/12/18 14:45:17	1.50
+++ src/usr.bin/ssh/PROTOCOL	2023/12/18 14:45:49	1.51
@@ -163,6 +163,25 @@
    duration of the connection (i.e. not just the first
    SSH2_MSG_NEWKEYS).
 
+1.10 transport: SSH2_MSG_EXT_INFO during user authentication
+
+This protocol extension allows the SSH2_MSG_EXT_INFO to be sent
+during user authentication. RFC8308 does allow a second
+SSH2_MSG_EXT_INFO notification, but it may only be sent at the end
+of user authentication and this is too late to signal per-user
+server signature algorithms.
+
+Support for receiving the SSH2_MSG_EXT_INFO message during user
+authentication is signalled by the client including a
+"ext-info-in-auth@openssh.com" key via its initial SSH2_MSG_EXT_INFO
+set after the SSH2_MSG_NEWKEYS message.
+
+A server that supports this extension MAY send a second
+SSH2_MSG_EXT_INFO message any time after the client's first
+SSH2_MSG_USERAUTH_REQUEST, regardless of whether it succeed or fails.
+The client SHOULD be prepared to update the server-sig-algs that
+it received during an earlier SSH2_MSG_EXT_INFO with the later one.
+
 2. Connection protocol changes
 
 2.1. connection: Channel write close extension "eow@openssh.com"
@@ -771,4 +790,4 @@
 OpenSSH extends the usual agent protocol. These changes are documented
 in the PROTOCOL.agent file.
 
-$OpenBSD: PROTOCOL,v 1.50 2023/12/18 14:45:17 djm Exp $
+$OpenBSD: PROTOCOL,v 1.51 2023/12/18 14:45:49 djm Exp $