kex.h revision 149749 
1/*	$OpenBSD: kex.h,v 1.37 2005/07/25 11:59:39 markus Exp $	*/
2
3/*
4 * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26#ifndef KEX_H
27#define KEX_H
28
29#include <openssl/evp.h>
30#include "buffer.h"
31#include "cipher.h"
32#include "key.h"
33
34#define	KEX_DH1		"diffie-hellman-group1-sha1"
35#define	KEX_DH14	"diffie-hellman-group14-sha1"
36#define	KEX_DHGEX	"diffie-hellman-group-exchange-sha1"
37
38#define COMP_NONE	0
39#define COMP_ZLIB	1
40#define COMP_DELAYED	2
41
42enum kex_init_proposals {
43	PROPOSAL_KEX_ALGS,
44	PROPOSAL_SERVER_HOST_KEY_ALGS,
45	PROPOSAL_ENC_ALGS_CTOS,
46	PROPOSAL_ENC_ALGS_STOC,
47	PROPOSAL_MAC_ALGS_CTOS,
48	PROPOSAL_MAC_ALGS_STOC,
49	PROPOSAL_COMP_ALGS_CTOS,
50	PROPOSAL_COMP_ALGS_STOC,
51	PROPOSAL_LANG_CTOS,
52	PROPOSAL_LANG_STOC,
53	PROPOSAL_MAX
54};
55
56enum kex_modes {
57	MODE_IN,
58	MODE_OUT,
59	MODE_MAX
60};
61
62enum kex_exchange {
63	KEX_DH_GRP1_SHA1,
64	KEX_DH_GRP14_SHA1,
65	KEX_DH_GEX_SHA1,
66	KEX_MAX
67};
68
69#define KEX_INIT_SENT	0x0001
70
71typedef struct Kex Kex;
72typedef struct Mac Mac;
73typedef struct Comp Comp;
74typedef struct Enc Enc;
75typedef struct Newkeys Newkeys;
76
77struct Enc {
78	char	*name;
79	Cipher	*cipher;
80	int	enabled;
81	u_int	key_len;
82	u_int	block_size;
83	u_char	*key;
84	u_char	*iv;
85};
86struct Mac {
87	char	*name;
88	int	enabled;
89	const EVP_MD	*md;
90	u_int	mac_len;
91	u_char	*key;
92	u_int	key_len;
93};
94struct Comp {
95	int	type;
96	int	enabled;
97	char	*name;
98};
99struct Newkeys {
100	Enc	enc;
101	Mac	mac;
102	Comp	comp;
103};
104struct Kex {
105	u_char	*session_id;
106	u_int	session_id_len;
107	Newkeys	*newkeys[MODE_MAX];
108	u_int	we_need;
109	int	server;
110	char	*name;
111	int	hostkey_type;
112	int	kex_type;
113	Buffer	my;
114	Buffer	peer;
115	int	done;
116	int	flags;
117	char	*client_version_string;
118	char	*server_version_string;
119	int	(*verify_host_key)(Key *);
120	Key	*(*load_host_key)(int);
121	int	(*host_key_index)(Key *);
122	void	(*kex[KEX_MAX])(Kex *);
123};
124
125Kex	*kex_setup(char *[PROPOSAL_MAX]);
126void	 kex_finish(Kex *);
127
128void	 kex_send_kexinit(Kex *);
129void	 kex_input_kexinit(int, u_int32_t, void *);
130void	 kex_derive_keys(Kex *, u_char *, BIGNUM *);
131
132Newkeys *kex_get_newkeys(int);
133
134void	 kexdh_client(Kex *);
135void	 kexdh_server(Kex *);
136void	 kexgex_client(Kex *);
137void	 kexgex_server(Kex *);
138
139u_char *
140kex_dh_hash(char *, char *, char *, int, char *, int, u_char *, int,
141    BIGNUM *, BIGNUM *, BIGNUM *);
142u_char *
143kexgex_hash(char *, char *, char *, int, char *, int, u_char *, int,
144    int, int, int, BIGNUM *, BIGNUM *, BIGNUM *, BIGNUM *, BIGNUM *);
145
146void
147derive_ssh1_session_id(BIGNUM *, BIGNUM *, u_int8_t[8], u_int8_t[16]);
148
149#if defined(DEBUG_KEX) || defined(DEBUG_KEXDH)
150void	dump_digest(char *, u_char *, int);
151#endif
152
153#endif
154