xref: /freebsd/crypto/openssh/kex.h (revision 7562eaabc01a48e6b11d5b558c41e3b92dae5c2d)
1 /*	$OpenBSD: kex.h,v 1.35 2004/06/13 12:53:24 djm 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 enum kex_init_proposals {
39 	PROPOSAL_KEX_ALGS,
40 	PROPOSAL_SERVER_HOST_KEY_ALGS,
41 	PROPOSAL_ENC_ALGS_CTOS,
42 	PROPOSAL_ENC_ALGS_STOC,
43 	PROPOSAL_MAC_ALGS_CTOS,
44 	PROPOSAL_MAC_ALGS_STOC,
45 	PROPOSAL_COMP_ALGS_CTOS,
46 	PROPOSAL_COMP_ALGS_STOC,
47 	PROPOSAL_LANG_CTOS,
48 	PROPOSAL_LANG_STOC,
49 	PROPOSAL_MAX
50 };
51 
52 enum kex_modes {
53 	MODE_IN,
54 	MODE_OUT,
55 	MODE_MAX
56 };
57 
58 enum kex_exchange {
59 	KEX_DH_GRP1_SHA1,
60 	KEX_DH_GRP14_SHA1,
61 	KEX_DH_GEX_SHA1,
62 	KEX_MAX
63 };
64 
65 #define KEX_INIT_SENT	0x0001
66 
67 typedef struct Kex Kex;
68 typedef struct Mac Mac;
69 typedef struct Comp Comp;
70 typedef struct Enc Enc;
71 typedef struct Newkeys Newkeys;
72 
73 struct Enc {
74 	char	*name;
75 	Cipher	*cipher;
76 	int	enabled;
77 	u_int	key_len;
78 	u_int	block_size;
79 	u_char	*key;
80 	u_char	*iv;
81 };
82 struct Mac {
83 	char	*name;
84 	int	enabled;
85 	const EVP_MD	*md;
86 	int	mac_len;
87 	u_char	*key;
88 	int	key_len;
89 };
90 struct Comp {
91 	int	type;
92 	int	enabled;
93 	char	*name;
94 };
95 struct Newkeys {
96 	Enc	enc;
97 	Mac	mac;
98 	Comp	comp;
99 };
100 struct Kex {
101 	u_char	*session_id;
102 	u_int	session_id_len;
103 	Newkeys	*newkeys[MODE_MAX];
104 	int	we_need;
105 	int	server;
106 	char	*name;
107 	int	hostkey_type;
108 	int	kex_type;
109 	Buffer	my;
110 	Buffer	peer;
111 	int	done;
112 	int	flags;
113 	char	*client_version_string;
114 	char	*server_version_string;
115 	int	(*verify_host_key)(Key *);
116 	Key	*(*load_host_key)(int);
117 	int	(*host_key_index)(Key *);
118 	void	(*kex[KEX_MAX])(Kex *);
119 };
120 
121 Kex	*kex_setup(char *[PROPOSAL_MAX]);
122 void	 kex_finish(Kex *);
123 
124 void	 kex_send_kexinit(Kex *);
125 void	 kex_input_kexinit(int, u_int32_t, void *);
126 void	 kex_derive_keys(Kex *, u_char *, BIGNUM *);
127 
128 Newkeys *kex_get_newkeys(int);
129 
130 void	 kexdh_client(Kex *);
131 void	 kexdh_server(Kex *);
132 void	 kexgex_client(Kex *);
133 void	 kexgex_server(Kex *);
134 
135 u_char *
136 kex_dh_hash(char *, char *, char *, int, char *, int, u_char *, int,
137     BIGNUM *, BIGNUM *, BIGNUM *);
138 u_char *
139 kexgex_hash(char *, char *, char *, int, char *, int, u_char *, int,
140     int, int, int, BIGNUM *, BIGNUM *, BIGNUM *, BIGNUM *, BIGNUM *);
141 
142 void
143 derive_ssh1_session_id(BIGNUM *, BIGNUM *, u_int8_t[8], u_int8_t[16]);
144 
145 #if defined(DEBUG_KEX) || defined(DEBUG_KEXDH)
146 void	dump_digest(char *, u_char *, int);
147 #endif
148 
149 #endif
150