upstream: Let allowed signers files used by ssh-keygen(1)

signatures support key lifetimes, and allow the verification mode to specify
a signature time to check at. This is intended for use by git to support
signing objects using ssh keys. ok dtucker@

OpenBSD-Commit-ID: 3e2c67b7dcd94f0610194d1e8e4907829a40cf31

1 files changed, 21 insertions, 11 deletions

diff --git a/sshkey.c b/sshkey.c
index 51482929..0dbc0d87 100644
--- a/sshkey.c
+++ b/sshkey.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshkey.c,v 1.118 2021/07/12 06:08:57 dtucker Exp $ */
+/* $OpenBSD: sshkey.c,v 1.119 2021/07/23 03:37:52 djm Exp $ */
 /*
  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2008 Alexander von Gernler.  All rights reserved.
@@ -3077,10 +3077,9 @@ sshkey_certify(struct sshkey *k, struct sshkey *ca, const char *alg,
 int
 sshkey_cert_check_authority(const struct sshkey *k,
     int want_host, int require_principal, int wildcard_pattern,
-    const char *name, const char **reason)
+    uint64_t verify_time, const char *name, const char **reason)
 {
 	u_int i, principal_matches;
-	time_t now = time(NULL);
 
 	if (reason == NULL)
 		return SSH_ERR_INVALID_ARGUMENT;
@@ -3099,16 +3098,11 @@ sshkey_cert_check_authority(const struct sshkey *k,
 			return SSH_ERR_KEY_CERT_INVALID;
 		}
 	}
-	if (now < 0) {
-		/* yikes - system clock before epoch! */
-		*reason = "Certificate invalid: not yet valid";
-		return SSH_ERR_KEY_CERT_INVALID;
-	}
-	if ((u_int64_t)now < k->cert->valid_after) {
+	if (verify_time < k->cert->valid_after) {
 		*reason = "Certificate invalid: not yet valid";
 		return SSH_ERR_KEY_CERT_INVALID;
 	}
-	if ((u_int64_t)now >= k->cert->valid_before) {
+	if (verify_time >= k->cert->valid_before) {
 		*reason = "Certificate invalid: expired";
 		return SSH_ERR_KEY_CERT_INVALID;
 	}
@@ -3141,13 +3135,29 @@ sshkey_cert_check_authority(const struct sshkey *k,
 }
 
 int
+sshkey_cert_check_authority_now(const struct sshkey *k,
+    int want_host, int require_principal, int wildcard_pattern,
+    const char *name, const char **reason)
+{
+	time_t now;
+
+	if ((now = time(NULL)) < 0) {
+		/* yikes - system clock before epoch! */
+		*reason = "Certificate invalid: not yet valid";
+		return SSH_ERR_KEY_CERT_INVALID;
+	}
+	return sshkey_cert_check_authority(k, want_host, require_principal,
+	    wildcard_pattern, (uint64_t)now, name, reason);
+}
+
+int
 sshkey_cert_check_host(const struct sshkey *key, const char *host,
     int wildcard_principals, const char *ca_sign_algorithms,
     const char **reason)
 {
 	int r;
 
-	if ((r = sshkey_cert_check_authority(key, 1, 0, wildcard_principals,
+	if ((r = sshkey_cert_check_authority_now(key, 1, 0, wildcard_principals,
 	    host, reason)) != 0)
 		return r;
 	if (sshbuf_len(key->cert->critical) != 0) {