kex.h revision 248619 
1/* $OpenBSD: kex.h,v 1.54 2013/01/08 18:49:04 markus Exp $ */
2/* $FreeBSD: head/crypto/openssh/kex.h 248619 2013-03-22 17:55:38Z des $ */
3
4/*
5 * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27#ifndef KEX_H
28#define KEX_H
29
30#include <signal.h>
31#include <openssl/evp.h>
32#include <openssl/hmac.h>
33#ifdef OPENSSL_HAS_ECC
34#include <openssl/ec.h>
35#endif
36
37#define KEX_COOKIE_LEN	16
38
39#define	KEX_DH1			"diffie-hellman-group1-sha1"
40#define	KEX_DH14		"diffie-hellman-group14-sha1"
41#define	KEX_DHGEX_SHA1		"diffie-hellman-group-exchange-sha1"
42#define	KEX_DHGEX_SHA256	"diffie-hellman-group-exchange-sha256"
43#define	KEX_RESUME		"resume@appgate.com"
44/* The following represents the family of ECDH methods */
45#define	KEX_ECDH_SHA2_STEM	"ecdh-sha2-"
46
47#define COMP_NONE	0
48#define COMP_ZLIB	1
49#define COMP_DELAYED	2
50
51enum kex_init_proposals {
52	PROPOSAL_KEX_ALGS,
53	PROPOSAL_SERVER_HOST_KEY_ALGS,
54	PROPOSAL_ENC_ALGS_CTOS,
55	PROPOSAL_ENC_ALGS_STOC,
56	PROPOSAL_MAC_ALGS_CTOS,
57	PROPOSAL_MAC_ALGS_STOC,
58	PROPOSAL_COMP_ALGS_CTOS,
59	PROPOSAL_COMP_ALGS_STOC,
60	PROPOSAL_LANG_CTOS,
61	PROPOSAL_LANG_STOC,
62	PROPOSAL_MAX
63};
64
65enum kex_modes {
66	MODE_IN,
67	MODE_OUT,
68	MODE_MAX
69};
70
71enum kex_exchange {
72	KEX_DH_GRP1_SHA1,
73	KEX_DH_GRP14_SHA1,
74	KEX_DH_GEX_SHA1,
75	KEX_DH_GEX_SHA256,
76	KEX_ECDH_SHA2,
77	KEX_MAX
78};
79
80#define KEX_INIT_SENT	0x0001
81
82typedef struct Kex Kex;
83typedef struct Mac Mac;
84typedef struct Comp Comp;
85typedef struct Enc Enc;
86typedef struct Newkeys Newkeys;
87
88struct Enc {
89	char	*name;
90	Cipher	*cipher;
91	int	enabled;
92	u_int	key_len;
93	u_int	iv_len;
94	u_int	block_size;
95	u_char	*key;
96	u_char	*iv;
97};
98struct Mac {
99	char	*name;
100	int	enabled;
101	u_int	mac_len;
102	u_char	*key;
103	u_int	key_len;
104	int	type;
105	int	etm;		/* Encrypt-then-MAC */
106	const EVP_MD	*evp_md;
107	HMAC_CTX	evp_ctx;
108	struct umac_ctx *umac_ctx;
109};
110struct Comp {
111	int	type;
112	int	enabled;
113	char	*name;
114};
115struct Newkeys {
116	Enc	enc;
117	Mac	mac;
118	Comp	comp;
119};
120struct Kex {
121	u_char	*session_id;
122	u_int	session_id_len;
123	Newkeys	*newkeys[MODE_MAX];
124	u_int	we_need;
125	int	server;
126	char	*name;
127	int	hostkey_type;
128	int	kex_type;
129	int	roaming;
130	Buffer	my;
131	Buffer	peer;
132	sig_atomic_t done;
133	int	flags;
134	const EVP_MD *evp_md;
135	char	*client_version_string;
136	char	*server_version_string;
137	int	(*verify_host_key)(Key *);
138	Key	*(*load_host_public_key)(int);
139	Key	*(*load_host_private_key)(int);
140	int	(*host_key_index)(Key *);
141	void	(*kex[KEX_MAX])(Kex *);
142};
143
144int	 kex_names_valid(const char *);
145
146#ifdef	NONE_CIPHER_ENABLED
147void	 kex_prop2buf(Buffer *, char *[PROPOSAL_MAX]);
148#endif
149
150Kex	*kex_setup(char *[PROPOSAL_MAX]);
151void	 kex_finish(Kex *);
152
153void	 kex_send_kexinit(Kex *);
154void	 kex_input_kexinit(int, u_int32_t, void *);
155void	 kex_derive_keys(Kex *, u_char *, u_int, BIGNUM *);
156
157Newkeys *kex_get_newkeys(int);
158
159void	 kexdh_client(Kex *);
160void	 kexdh_server(Kex *);
161void	 kexgex_client(Kex *);
162void	 kexgex_server(Kex *);
163void	 kexecdh_client(Kex *);
164void	 kexecdh_server(Kex *);
165
166void
167kex_dh_hash(char *, char *, char *, int, char *, int, u_char *, int,
168    BIGNUM *, BIGNUM *, BIGNUM *, u_char **, u_int *);
169void
170kexgex_hash(const EVP_MD *, char *, char *, char *, int, char *,
171    int, u_char *, int, int, int, int, BIGNUM *, BIGNUM *, BIGNUM *,
172    BIGNUM *, BIGNUM *, u_char **, u_int *);
173#ifdef OPENSSL_HAS_ECC
174void
175kex_ecdh_hash(const EVP_MD *, const EC_GROUP *, char *, char *, char *, int,
176    char *, int, u_char *, int, const EC_POINT *, const EC_POINT *,
177    const BIGNUM *, u_char **, u_int *);
178int	kex_ecdh_name_to_nid(const char *);
179const EVP_MD *kex_ecdh_name_to_evpmd(const char *);
180#else
181# define kex_ecdh_name_to_nid(x) (-1)
182# define kex_ecdh_name_to_evpmd(x) (NULL)
183#endif
184
185void
186derive_ssh1_session_id(BIGNUM *, BIGNUM *, u_int8_t[8], u_int8_t[16]);
187
188#if defined(DEBUG_KEX) || defined(DEBUG_KEXDH) || defined(DEBUG_KEXECDH)
189void	dump_digest(char *, u_char *, int);
190#endif
191
192#endif
193