prepare for multiple names for authmethods

allow authentication methods to have one additional name beyond their
primary name.

allow lookup by this synonym

Use primary name for authentication decisions, e.g. for
PermitRootLogin=publickey

Pass actual invoked name to the authmethods, so they can tell whether they
were requested via the their primary name or synonym.

ok markus@

1 files changed, 4 insertions, 3 deletions

diff --git a/usr.bin/ssh/auth2-hostbased.c b/usr.bin/ssh/auth2-hostbased.c
index cd9523954b2..f99f93e4616 100644
--- a/usr.bin/ssh/auth2-hostbased.c
+++ b/usr.bin/ssh/auth2-hostbased.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: auth2-hostbased.c,v 1.47 2021/07/23 03:37:52 djm Exp $ */
+/* $OpenBSD: auth2-hostbased.c,v 1.48 2021/12/19 22:12:07 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  *
@@ -56,7 +56,7 @@
 extern ServerOptions options;
 
 static int
-userauth_hostbased(struct ssh *ssh)
+userauth_hostbased(struct ssh *ssh, const char *method)
 {
 	Authctxt *authctxt = ssh->authctxt;
 	struct sshbuf *b;
@@ -131,7 +131,7 @@ userauth_hostbased(struct ssh *ssh)
 	    (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
 	    (r = sshbuf_put_cstring(b, authctxt->user)) != 0 ||
 	    (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
-	    (r = sshbuf_put_cstring(b, "hostbased")) != 0 ||
+	    (r = sshbuf_put_cstring(b, method)) != 0 ||
 	    (r = sshbuf_put_string(b, pkalg, alen)) != 0 ||
 	    (r = sshbuf_put_string(b, pkblob, blen)) != 0 ||
 	    (r = sshbuf_put_cstring(b, chost)) != 0 ||
@@ -254,6 +254,7 @@ hostbased_key_allowed(struct ssh *ssh, struct passwd *pw,
 
 Authmethod method_hostbased = {
 	"hostbased",
+	NULL,
 	userauth_hostbased,
 	&options.hostbased_authentication
 };