From 1ee0a16e07b6f0847ff463d7b5221c4bf1876e25 Mon Sep 17 00:00:00 2001 From: "djm@openbsd.org" Date: Wed, 6 Sep 2023 23:18:15 +0000 Subject: [PATCH] upstream: handle cr+lf (instead of just cr) in sshsig signature files OpenBSD-Commit-ID: 647460a212b916540016d066568816507375fd7f --- sshsig.c | 27 +++++++++++++++++++-------- 1 file changed, 19 insertions(+), 8 deletions(-) diff --git a/sshsig.c b/sshsig.c index 854d67322..d219db90e 100644 --- a/sshsig.c +++ b/sshsig.c @@ -1,4 +1,4 @@ -/* $OpenBSD: sshsig.c,v 1.32 2023/04/06 03:56:02 djm Exp $ */ +/* $OpenBSD: sshsig.c,v 1.33 2023/09/06 23:18:15 djm Exp $ */ /* * Copyright (c) 2019 Google LLC * @@ -38,7 +38,7 @@ #define SIG_VERSION 0x01 #define MAGIC_PREAMBLE "SSHSIG" #define MAGIC_PREAMBLE_LEN (sizeof(MAGIC_PREAMBLE) - 1) -#define BEGIN_SIGNATURE "-----BEGIN SSH SIGNATURE-----\n" +#define BEGIN_SIGNATURE "-----BEGIN SSH SIGNATURE-----" #define END_SIGNATURE "-----END SSH SIGNATURE-----" #define RSA_SIGN_ALG "rsa-sha2-512" /* XXX maybe make configurable */ #define RSA_SIGN_ALLOWED "rsa-sha2-512,rsa-sha2-256" @@ -59,8 +59,7 @@ sshsig_armor(const struct sshbuf *blob, struct sshbuf **out) goto out; } - if ((r = sshbuf_put(buf, BEGIN_SIGNATURE, - sizeof(BEGIN_SIGNATURE)-1)) != 0) { + if ((r = sshbuf_putf(buf, "%s\n", BEGIN_SIGNATURE)) != 0) { error_fr(r, "sshbuf_putf"); goto out; } @@ -99,23 +98,35 @@ sshsig_dearmor(struct sshbuf *sig, struct sshbuf **out) return SSH_ERR_ALLOC_FAIL; } + /* Expect and consume preamble + lf/crlf */ if ((r = sshbuf_cmp(sbuf, 0, BEGIN_SIGNATURE, sizeof(BEGIN_SIGNATURE)-1)) != 0) { error("Couldn't parse signature: missing header"); goto done; } - if ((r = sshbuf_consume(sbuf, sizeof(BEGIN_SIGNATURE)-1)) != 0) { error_fr(r, "consume"); goto done; } - + if ((r = sshbuf_cmp(sbuf, 0, "\r\n", 2)) == 0) + eoffset = 2; + else if ((r = sshbuf_cmp(sbuf, 0, "\n", 1)) == 0) + eoffset = 1; + else { + r = SSH_ERR_INVALID_FORMAT; + error_f("no header eol"); + goto done; + } + if ((r = sshbuf_consume(sbuf, eoffset)) != 0) { + error_fr(r, "consume eol"); + goto done; + } + /* Find and consume lf + suffix (any prior cr would be ignored) */ if ((r = sshbuf_find(sbuf, 0, "\n" END_SIGNATURE, - sizeof("\n" END_SIGNATURE)-1, &eoffset)) != 0) { + sizeof(END_SIGNATURE), &eoffset)) != 0) { error("Couldn't parse signature: missing footer"); goto done; } - if ((r = sshbuf_consume_end(sbuf, sshbuf_len(sbuf)-eoffset)) != 0) { error_fr(r, "consume"); goto done; -- 2.47.3