Don't log NULL hostname in restricted agent code, printf("%s", NULL) is

not safe on all platforms.  with & ok djm

diff --git a/usr.bin/ssh/ssh-agent.c b/usr.bin/ssh/ssh-agent.c
index f402d91..c459dbe 100644 (file)
--- a/usr.bin/ssh/ssh-agent.c
+++ b/usr.bin/ssh/ssh-agent.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-agent.c,v 1.285 2022/01/01 04:18:06 djm Exp $ */
+/* $OpenBSD: ssh-agent.c,v 1.286 2022/01/12 03:30:32 dtucker Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -250,6 +250,7 @@ match_key_hop(const char *tag, const struct sshkey *key,
     const struct dest_constraint_hop *dch)
 {
        const char *reason = NULL;
+       const char *hostname = dch->hostname ? dch->hostname : "(ORIGIN)";
        u_int i;
        char *fp;
 
@@ -260,7 +261,7 @@ match_key_hop(const char *tag, const struct sshkey *key,
            SSH_FP_DEFAULT)) == NULL)
                fatal_f("fingerprint failed");
        debug3_f("%s: entering hostname %s, requested key %s %s, %u keys avail",
-           tag, dch->hostname, sshkey_type(key), fp, dch->nkeys);
+           tag, hostname, sshkey_type(key), fp, dch->nkeys);
        free(fp);
        for (i = 0; i < dch->nkeys; i++) {
                if (dch->keys[i] == NULL)
@@ -287,10 +288,10 @@ match_key_hop(const char *tag, const struct sshkey *key,
                        return -1; /* shouldn't happen */
                if (!sshkey_equal(key->cert->signature_key, dch->keys[i]))
                        continue;
-               if (sshkey_cert_check_host(key, dch->hostname, 1,
+               if (sshkey_cert_check_host(key, hostname, 1,
                    SSH_ALLOWED_CA_SIGALGS, &reason) != 0) {
                        debug_f("cert %s / hostname %s rejected: %s",
-                           key->cert->key_id, dch->hostname, reason);
+                           key->cert->key_id, hostname, reason);
                        continue;
                }
                return 0;