xref: /netbsd-src/crypto/external/bsd/openssh/dist/kex.h (revision 413d532bcc3f62d122e56d92e13ac64825a40baf)
1 /*	$NetBSD: kex.h,v 1.7 2013/11/08 19:18:25 christos Exp $	*/
2 /* $OpenBSD: kex.h,v 1.56 2013/07/19 07:37:48 markus Exp $ */
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 <openssl/evp.h>
31 #include <openssl/hmac.h>
32 #include <openssl/ec.h>
33 
34 #define KEX_COOKIE_LEN	16
35 
36 #define	KEX_DH1			"diffie-hellman-group1-sha1"
37 #define	KEX_DH14		"diffie-hellman-group14-sha1"
38 #define	KEX_DHGEX_SHA1		"diffie-hellman-group-exchange-sha1"
39 #define	KEX_DHGEX_SHA256	"diffie-hellman-group-exchange-sha256"
40 #define	KEX_RESUME		"resume@appgate.com"
41 #define	KEX_ECDH_SHA2_NISTP256	"ecdh-sha2-nistp256"
42 #define	KEX_ECDH_SHA2_NISTP384	"ecdh-sha2-nistp384"
43 #define	KEX_ECDH_SHA2_NISTP521	"ecdh-sha2-nistp521"
44 
45 #define COMP_NONE	0
46 #define COMP_ZLIB	1
47 #define COMP_DELAYED	2
48 
49 enum kex_init_proposals {
50 	PROPOSAL_KEX_ALGS,
51 	PROPOSAL_SERVER_HOST_KEY_ALGS,
52 	PROPOSAL_ENC_ALGS_CTOS,
53 	PROPOSAL_ENC_ALGS_STOC,
54 	PROPOSAL_MAC_ALGS_CTOS,
55 	PROPOSAL_MAC_ALGS_STOC,
56 	PROPOSAL_COMP_ALGS_CTOS,
57 	PROPOSAL_COMP_ALGS_STOC,
58 	PROPOSAL_LANG_CTOS,
59 	PROPOSAL_LANG_STOC,
60 	PROPOSAL_MAX
61 };
62 
63 enum kex_modes {
64 	MODE_IN,
65 	MODE_OUT,
66 	MODE_MAX
67 };
68 
69 enum kex_exchange {
70 	KEX_DH_GRP1_SHA1,
71 	KEX_DH_GRP14_SHA1,
72 	KEX_DH_GEX_SHA1,
73 	KEX_DH_GEX_SHA256,
74 	KEX_ECDH_SHA2,
75 	KEX_MAX
76 };
77 
78 #define KEX_INIT_SENT	0x0001
79 
80 typedef struct Kex Kex;
81 typedef struct Mac Mac;
82 typedef struct Comp Comp;
83 typedef struct Enc Enc;
84 typedef struct Newkeys Newkeys;
85 
86 struct Enc {
87 	char	*name;
88 	const Cipher *cipher;
89 	int	enabled;
90 	u_int	key_len;
91 	u_int	iv_len;
92 	u_int	block_size;
93 	u_char	*key;
94 	u_char	*iv;
95 };
96 struct Mac {
97 	char	*name;
98 	int	enabled;
99 	u_int	mac_len;
100 	u_char	*key;
101 	u_int	key_len;
102 	int	type;
103 	int	etm;		/* Encrypt-then-MAC */
104 	const EVP_MD	*evp_md;
105 	HMAC_CTX	evp_ctx;
106 	struct umac_ctx *umac_ctx;
107 };
108 struct Comp {
109 	int	type;
110 	int	enabled;
111 	char	*name;
112 };
113 struct Newkeys {
114 	Enc	enc;
115 	Mac	mac;
116 	Comp	comp;
117 };
118 struct Kex {
119 	u_char	*session_id;
120 	u_int	session_id_len;
121 	Newkeys	*newkeys[MODE_MAX];
122 	u_int	we_need;
123 	int	server;
124 	char	*name;
125 	int	hostkey_type;
126 	int	kex_type;
127 	int	roaming;
128 	Buffer	my;
129 	Buffer	peer;
130 	sig_atomic_t done;
131 	int	flags;
132 	const EVP_MD *evp_md;
133 	int	ec_nid;
134 	char	*client_version_string;
135 	char	*server_version_string;
136 	int	(*verify_host_key)(Key *);
137 	Key	*(*load_host_public_key)(int);
138 	Key	*(*load_host_private_key)(int);
139 	int	(*host_key_index)(Key *);
140 	void    (*sign)(Key *, Key *, u_char **, u_int *, u_char *, u_int);
141 	void	(*kex[KEX_MAX])(Kex *);
142 };
143 
144 void	 kex_prop2buf(Buffer *, const char *proposal[PROPOSAL_MAX]);
145 
146 int	 kex_names_valid(const char *);
147 char	*kex_alg_list(void);
148 
149 Kex	*kex_setup(const char *[PROPOSAL_MAX]);
150 void	 kex_finish(Kex *);
151 
152 void	 kex_send_kexinit(Kex *);
153 void	 kex_input_kexinit(int, u_int32_t, void *);
154 void	 kex_derive_keys(Kex *, u_char *, u_int, BIGNUM *);
155 
156 Newkeys *kex_get_newkeys(int);
157 
158 void	 kexdh_client(Kex *);
159 void	 kexdh_server(Kex *);
160 void	 kexgex_client(Kex *);
161 void	 kexgex_server(Kex *);
162 void	 kexecdh_client(Kex *);
163 void	 kexecdh_server(Kex *);
164 
165 void
166 kex_dh_hash(char *, char *, char *, int, char *, int, u_char *, int,
167     BIGNUM *, BIGNUM *, BIGNUM *, u_char **, u_int *);
168 void
169 kexgex_hash(const EVP_MD *, char *, char *, char *, int, char *,
170     int, u_char *, int, int, int, int, BIGNUM *, BIGNUM *, BIGNUM *,
171     BIGNUM *, BIGNUM *, u_char **, u_int *);
172 void
173 kex_ecdh_hash(const EVP_MD *, const EC_GROUP *, char *, char *, char *, int,
174     char *, int, u_char *, int, const EC_POINT *, const EC_POINT *,
175     const BIGNUM *, u_char **, u_int *);
176 
177 void
178 derive_ssh1_session_id(BIGNUM *, BIGNUM *, u_int8_t[8], u_int8_t[16]);
179 
180 #if defined(DEBUG_KEX) || defined(DEBUG_KEXDH) || defined(DEBUG_KEXECDH)
181 void	dump_digest(char *, u_char *, int);
182 #endif
183 
184 #endif
185