From 1b11ea7c58cd5c59838b5fa574cd456d6047b2d4 Mon Sep 17 00:00:00 2001 From: "markus@openbsd.org" Date: Fri, 23 Feb 2018 15:58:37 +0000 Subject: upstream: Add experimental support for PQC XMSS keys (Extended Hash-Based Signatures) The code is not compiled in by default (see WITH_XMSS in Makefile.inc) Joint work with stefan-lukas_gazdag at genua.eu See https://tools.ietf.org/html/draft-irtf-cfrg-xmss-hash-based-signatures-12 ok djm@ OpenBSD-Commit-ID: ef3eccb96762a5d6f135d7daeef608df7776a7ac --- ssh-add.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 69 insertions(+), 5 deletions(-) (limited to 'ssh-add.c') diff --git a/ssh-add.c b/ssh-add.c index 2afd48330..adcc45998 100644 --- a/ssh-add.c +++ b/ssh-add.c @@ -1,4 +1,4 @@ -/* $OpenBSD: ssh-add.c,v 1.134 2017/08/29 09:42:29 dlg Exp $ */ +/* $OpenBSD: ssh-add.c,v 1.135 2018/02/23 15:58:37 markus Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland @@ -78,6 +78,7 @@ static char *default_files[] = { #endif #endif /* WITH_OPENSSL */ _PATH_SSH_CLIENT_ID_ED25519, + _PATH_SSH_CLIENT_ID_XMSS, NULL }; @@ -89,6 +90,10 @@ static int lifetime = 0; /* User has to confirm key use */ static int confirm = 0; +/* Maximum number of signatures (XMSS) */ +static u_int maxsign = 0; +static u_int minleft = 0; + /* we keep a cache of one passphrase */ static char *pass = NULL; static void @@ -190,7 +195,10 @@ add_file(int agent_fd, const char *filename, int key_only, int qflag) char *comment = NULL; char msg[1024], *certpath = NULL; int r, fd, ret = -1; + size_t i; + u_int32_t left; struct sshbuf *keyblob; + struct ssh_identitylist *idlist; if (strcmp(filename, "-") == 0) { fd = STDIN_FILENO; @@ -268,8 +276,40 @@ add_file(int agent_fd, const char *filename, int key_only, int qflag) comment = xstrdup(filename); sshbuf_free(keyblob); + /* For XMSS */ + if ((r = sshkey_set_filename(private, filename)) != 0) { + fprintf(stderr, "Could not add filename to private key: %s (%s)\n", + filename, comment); + goto out; + } + if (maxsign && minleft && + (r = ssh_fetch_identitylist(agent_fd, &idlist)) == 0) { + for (i = 0; i < idlist->nkeys; i++) { + if (!sshkey_equal_public(idlist->keys[i], private)) + continue; + left = sshkey_signatures_left(idlist->keys[i]); + if (left < minleft) { + fprintf(stderr, + "Only %d signatures left.\n", left); + break; + } + fprintf(stderr, "Skipping update: "); + if (left == minleft) { + fprintf(stderr, + "required signatures left (%d).\n", left); + } else { + fprintf(stderr, + "more signatures left (%d) than" + " required (%d).\n", left, minleft); + } + ssh_free_identitylist(idlist); + goto out; + } + ssh_free_identitylist(idlist); + } + if ((r = ssh_add_identity_constrained(agent_fd, private, comment, - lifetime, confirm)) == 0) { + lifetime, confirm, maxsign)) == 0) { fprintf(stderr, "Identity added: %s (%s)\n", filename, comment); ret = 0; if (lifetime != 0) @@ -317,7 +357,7 @@ add_file(int agent_fd, const char *filename, int key_only, int qflag) sshkey_free(cert); if ((r = ssh_add_identity_constrained(agent_fd, private, comment, - lifetime, confirm)) != 0) { + lifetime, confirm, maxsign)) != 0) { error("Certificate %s (%s) add failed: %s", certpath, private->cert->key_id, ssh_err(r)); goto out; @@ -368,6 +408,7 @@ list_identities(int agent_fd, int do_fp) char *fp; int r; struct ssh_identitylist *idlist; + u_int32_t left; size_t i; if ((r = ssh_fetch_identitylist(agent_fd, &idlist)) != 0) { @@ -392,7 +433,12 @@ list_identities(int agent_fd, int do_fp) ssh_err(r)); continue; } - fprintf(stdout, " %s\n", idlist->comments[i]); + fprintf(stdout, " %s", idlist->comments[i]); + left = sshkey_signatures_left(idlist->keys[i]); + if (left > 0) + fprintf(stdout, + " [signatures left %d]", left); + fprintf(stdout, "\n"); } } ssh_free_identitylist(idlist); @@ -454,6 +500,8 @@ usage(void) fprintf(stderr, " -L List public key parameters of all identities.\n"); fprintf(stderr, " -k Load only keys and not certificates.\n"); fprintf(stderr, " -c Require confirmation to sign using identities\n"); + fprintf(stderr, " -m minleft Maxsign is only changed if less than minleft are left (for XMSS)\n"); + fprintf(stderr, " -M maxsign Maximum number of signatures allowed (for XMSS)\n"); fprintf(stderr, " -t life Set lifetime (in seconds) when adding identities.\n"); fprintf(stderr, " -d Delete identity.\n"); fprintf(stderr, " -D Delete all identities.\n"); @@ -500,7 +548,7 @@ main(int argc, char **argv) exit(2); } - while ((ch = getopt(argc, argv, "klLcdDxXE:e:qs:t:")) != -1) { + while ((ch = getopt(argc, argv, "klLcdDxXE:e:M:m:qs:t:")) != -1) { switch (ch) { case 'E': fingerprint_hash = ssh_digest_alg_by_name(optarg); @@ -525,6 +573,22 @@ main(int argc, char **argv) case 'c': confirm = 1; break; + case 'm': + minleft = (int)strtonum(optarg, 1, UINT_MAX, NULL); + if (minleft == 0) { + usage(); + ret = 1; + goto done; + } + break; + case 'M': + maxsign = (int)strtonum(optarg, 1, UINT_MAX, NULL); + if (maxsign == 0) { + usage(); + ret = 1; + goto done; + } + break; case 'd': deleting = 1; break; -- cgit v1.2.3