Add new structure for signature options

This is populated during signature verification with additional fields
that are present in and covered by the signature. At the moment, it is
only used to record security key-specific options, especially the flags
field.

with and ok markus@

1 files changed, 10 insertions, 3 deletions

diff --git a/usr.bin/ssh/ssh-keygen.c b/usr.bin/ssh/ssh-keygen.c
index 22e7317b650..fde77f6ab93 100644
--- a/usr.bin/ssh/ssh-keygen.c
+++ b/usr.bin/ssh/ssh-keygen.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-keygen.c,v 1.369 2019/11/18 23:16:49 naddy Exp $ */
+/* $OpenBSD: ssh-keygen.c,v 1.370 2019/11/25 00:51:37 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1994 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -570,7 +570,7 @@ do_convert_private_ssh2(struct sshbuf *b)
 	if (sshkey_sign(key, &sig, &slen, data, sizeof(data),
 	    NULL, NULL, 0) != 0 ||
 	    sshkey_verify(key, sig, slen, data, sizeof(data),
-	    NULL, 0) != 0) {
+	    NULL, 0, NULL) != 0) {
 		sshkey_free(key);
 		free(sig);
 		return NULL;
@@ -2639,7 +2639,9 @@ verify(const char *signature, const char *sig_namespace, const char *principal,
 	struct sshbuf *sigbuf = NULL, *abuf = NULL;
 	struct sshkey *sign_key = NULL;
 	char *fp = NULL;
+	struct sshkey_sig_details *sig_details = NULL;
 
+	memset(&sig_details, 0, sizeof(sig_details));
 	if ((abuf = sshbuf_new()) == NULL)
 		fatal("%s: sshbuf_new() failed", __func__);
 
@@ -2657,13 +2659,17 @@ verify(const char *signature, const char *sig_namespace, const char *principal,
 		return r;
 	}
 	if ((r = sshsig_verify_fd(sigbuf, STDIN_FILENO, sig_namespace,
-	    &sign_key)) != 0)
+	    &sign_key, &sig_details)) != 0)
 		goto done; /* sshsig_verify() prints error */
 
 	if ((fp = sshkey_fingerprint(sign_key, fingerprint_hash,
 	    SSH_FP_DEFAULT)) == NULL)
 		fatal("%s: sshkey_fingerprint failed", __func__);
 	debug("Valid (unverified) signature from key %s", fp);
+	if (sig_details != NULL) {
+		debug2("%s: signature details: counter = %u, flags = 0x%02x",
+		    __func__, sig_details->sk_counter, sig_details->sk_flags);
+	}
 	free(fp);
 	fp = NULL;
 
@@ -2708,6 +2714,7 @@ done:
 	sshbuf_free(sigbuf);
 	sshbuf_free(abuf);
 	sshkey_free(sign_key);
+	sshkey_sig_details_free(sig_details);
 	free(fp);
 	return ret;
 }