From 0a1e75499e2c6fc258ee903645c878480949f362 Mon Sep 17 00:00:00 2001 From: "djm@openbsd.org" Date: Fri, 18 Oct 2024 05:14:51 +0000 Subject: upstream: in _ssh_order_hostkeyalgs() consider ECDSA curve type when arranging the hostkey algorithms. AFAIK this code is unused in OpenSSH, but I guess others are using it based on GHPR387 from Pawel Jakub Dawidek OpenBSD-Commit-ID: 4d462495ac0c40f7b7dd66178e0005b9b2128225 --- ssh_api.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/ssh_api.c b/ssh_api.c index 5faaffd16..7bdcee148 100644 --- a/ssh_api.c +++ b/ssh_api.c @@ -1,4 +1,4 @@ -/* $OpenBSD: ssh_api.c,v 1.31 2024/09/09 02:39:57 djm Exp $ */ +/* $OpenBSD: ssh_api.c,v 1.32 2024/10/18 05:14:51 djm Exp $ */ /* * Copyright (c) 2012 Markus Friedl. All rights reserved. * @@ -532,7 +532,7 @@ _ssh_order_hostkeyalgs(struct ssh *ssh) char *orig, *avail, *oavail = NULL, *alg, *replace = NULL; char **proposal; size_t maxlen; - int ktype, r; + int ktype, nid, r; /* XXX we de-serialize ssh->kex->my, modify it, and change it */ if ((r = kex_buf2prop(ssh->kex->my, NULL, &proposal)) != 0) @@ -551,15 +551,20 @@ _ssh_order_hostkeyalgs(struct ssh *ssh) while ((alg = strsep(&avail, ",")) && *alg != '\0') { if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC) continue; + nid = sshkey_ecdsa_nid_from_name(alg); TAILQ_FOREACH(k, &ssh->public_keys, next) { - if (k->key->type == ktype || - (sshkey_is_cert(k->key) && k->key->type == - sshkey_type_plain(ktype))) { - if (*replace != '\0') - strlcat(replace, ",", maxlen); - strlcat(replace, alg, maxlen); - break; - } + if (k->key->type != ktype && + (!sshkey_is_cert(k->key) || + k->key->type != sshkey_type_plain(ktype))) + continue; + if (sshkey_type_plain(k->key->type) == KEY_ECDSA && + k->key->ecdsa_nid != nid) + continue; + /* Candidate */ + if (*replace != '\0') + strlcat(replace, ",", maxlen); + strlcat(replace, alg, maxlen); + break; } } if (*replace != '\0') { -- cgit v1.2.3