upstream: support for user-verified FIDO keys

FIDO2 supports a notion of "user verification" where the user is
required to demonstrate their identity to the token before particular
operations (e.g. signing). Typically this is done by authenticating
themselves using a PIN that has been set on the token.

This adds support for generating and using user verified keys where
the verification happens via PIN (other options might be added in the
future, but none are in common use now). Practically, this adds
another key generation option "verify-required" that yields a key that
requires a PIN before each authentication.

feedback markus@ and Pedro Martelletto; ok markus@

OpenBSD-Commit-ID: 57fd461e4366f87c47502c5614ec08573e6d6a15

1 files changed, 6 insertions, 5 deletions

diff --git a/sshkey.h b/sshkey.h
index 9c1d4f637..2d8b62497 100644
--- a/sshkey.h
+++ b/sshkey.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshkey.h,v 1.45 2020/04/08 00:08:46 djm Exp $ */
+/* $OpenBSD: sshkey.h,v 1.46 2020/08/27 01:06:19 djm Exp $ */
 
 /*
  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
@@ -200,12 +200,13 @@ size_t	 sshkey_format_cert_validity(const struct sshkey_cert *,
 int      sshkey_check_cert_sigtype(const struct sshkey *, const char *);
 
 int      sshkey_certify(struct sshkey *, struct sshkey *,
-    const char *, const char *);
+    const char *, const char *, const char *);
 /* Variant allowing use of a custom signature function (e.g. for ssh-agent) */
 typedef int sshkey_certify_signer(struct sshkey *, u_char **, size_t *,
-    const u_char *, size_t, const char *, const char *, u_int, void *);
+    const u_char *, size_t, const char *, const char *, const char *,
+    u_int, void *);
 int      sshkey_certify_custom(struct sshkey *, struct sshkey *, const char *,
-    const char *, sshkey_certify_signer *, void *);
+    const char *, const char *, sshkey_certify_signer *, void *);
 
 int              sshkey_ecdsa_nid_from_name(const char *);
 int              sshkey_curve_name_to_nid(const char *);
@@ -234,7 +235,7 @@ int	 sshkey_plain_to_blob(const struct sshkey *, u_char **, size_t *);
 int      sshkey_putb_plain(const struct sshkey *, struct sshbuf *);
 
 int      sshkey_sign(struct sshkey *, u_char **, size_t *,
-    const u_char *, size_t, const char *, const char *, u_int);
+    const u_char *, size_t, const char *, const char *, const char *, u_int);
 int      sshkey_verify(const struct sshkey *, const u_char *, size_t,
     const u_char *, size_t, const char *, u_int, struct sshkey_sig_details **);
 int      sshkey_check_sigtype(const u_char *, size_t, const char *);