diff options
author | Bernhard Schmidt <berni@debian.org> | 2020-08-15 21:29:50 +0200 |
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committer | Bernhard Schmidt <berni@debian.org> | 2020-08-15 21:29:50 +0200 |
commit | 1079962e4c06f88a54e50d997c1b7e84303d30b4 (patch) | |
tree | 4d019426928435425214ccedd6f89b70dbdf035d /src/openvpn/ssl_ncp.h | |
parent | 620785fe268a1221c1ba7a9cb5a70f3140a4f1ca (diff) |
New upstream version 2.5~beta1upstream/2.5_beta1
Diffstat (limited to 'src/openvpn/ssl_ncp.h')
-rw-r--r-- | src/openvpn/ssl_ncp.h | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/src/openvpn/ssl_ncp.h b/src/openvpn/ssl_ncp.h new file mode 100644 index 0000000..39158a5 --- /dev/null +++ b/src/openvpn/ssl_ncp.h @@ -0,0 +1,118 @@ +/* + * OpenVPN -- An application to securely tunnel IP networks + * over a single TCP/UDP port, with support for SSL/TLS-based + * session authentication and key exchange, + * packet encryption, packet authentication, and + * packet compression. + * + * Copyright (C) 2002-2018 OpenVPN Inc <sales@openvpn.net> + * Copyright (C) 2010-2018 Fox Crypto B.V. <openvpn@fox-it.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +/** + * @file Control Channel SSL/Data dynamic negotion Module + * This file is split from ssl.h to be able to unit test it. + */ + +#ifndef OPENVPN_SSL_NCP_H +#define OPENVPN_SSL_NCP_H + +#include "buffer.h" +#include "options.h" + +/** + * Returns whether the client supports NCP either by + * announcing IV_NCP>=2 or the IV_CIPHERS list + */ +bool +tls_peer_supports_ncp(const char *peer_info); + +/* forward declaration to break include dependency loop */ +struct context; + +/** + * Checks whether the cipher negotiation is in an acceptable state + * and we continue to connect or should abort. + * + * @return Wether the client NCP process suceeded or failed + */ +bool +check_pull_client_ncp(struct context *c, int found); + +/** + * Iterates through the ciphers in server_list and return the first + * cipher that is also supported by the peer according to the IV_NCP + * and IV_CIPHER values in peer_info. + * + * We also accept a cipher that is the remote cipher of the client for + * "Poor man's NCP": Use peer cipher if it is an allowed (NCP) cipher. + * Allows non-NCP peers to upgrade their cipher individually. + * + * Make sure to call tls_session_update_crypto_params() after calling this + * function. + * + * @param gc gc arena that is ONLY used to allocate the returned string + * + * @returns NULL if no common cipher is available, otherwise the best common + * cipher + */ +char * +ncp_get_best_cipher(const char *server_list, const char *peer_info, + const char *remote_cipher, struct gc_arena *gc); + + +/** + * Returns the support cipher list from the peer according to the IV_NCP + * and IV_CIPHER values in peer_info. + * + * @returns Either a string containing the ncp list that is either static + * or allocated via gc. If no information is available an empty string + * ("") is returned. + */ +const char * +tls_peer_ncp_list(const char *peer_info, struct gc_arena *gc); + +/** + * Check whether the ciphers in the supplied list are supported. + * + * @param list Colon-separated list of ciphers + * @parms gc gc_arena to allocate the returned string + * + * @returns colon separated string of normalised (via + * translate_cipher_name_from_openvpn) and + * zero terminated string iff all ciphers + * in list are supported and the total length + * is short than MAX_NCP_CIPHERS_LENGTH. NULL + * otherwise. + */ +char * +mutate_ncp_cipher_list(const char *list, struct gc_arena *gc); + +/** + * Return true iff item is present in the colon-separated zero-terminated + * cipher list. + */ +bool tls_item_in_cipher_list(const char *item, const char *list); + +/** + * The maximum length of a ncp-cipher string that is accepted. + * + * Since this list needs to be pushed as IV_CIPHERS, we are conservative + * about its length. + */ +#define MAX_NCP_CIPHERS_LENGTH 127 + +#endif /* ifndef OPENVPN_SSL_NCP_H */ |