1 /* $OpenBSD: kex.h,v 1.61 2014/01/25 10:12:50 dtucker Exp $ */
5 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
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.
31 #include <openssl/evp.h>
32 #include <openssl/hmac.h>
33 #ifdef OPENSSL_HAS_ECC
34 #include <openssl/ec.h>
37 #define KEX_COOKIE_LEN 16
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 #define KEX_ECDH_SHA2_NISTP256 "ecdh-sha2-nistp256"
45 #define KEX_ECDH_SHA2_NISTP384 "ecdh-sha2-nistp384"
46 #define KEX_ECDH_SHA2_NISTP521 "ecdh-sha2-nistp521"
47 #define KEX_CURVE25519_SHA256 "curve25519-sha256@libssh.org"
51 #define COMP_DELAYED 2
53 enum kex_init_proposals {
55 PROPOSAL_SERVER_HOST_KEY_ALGS,
56 PROPOSAL_ENC_ALGS_CTOS,
57 PROPOSAL_ENC_ALGS_STOC,
58 PROPOSAL_MAC_ALGS_CTOS,
59 PROPOSAL_MAC_ALGS_STOC,
60 PROPOSAL_COMP_ALGS_CTOS,
61 PROPOSAL_COMP_ALGS_STOC,
83 #define KEX_INIT_SENT 0x0001
85 typedef struct Kex Kex;
86 typedef struct Mac Mac;
87 typedef struct Comp Comp;
88 typedef struct Enc Enc;
89 typedef struct Newkeys Newkeys;
108 int etm; /* Encrypt-then-MAC */
109 const EVP_MD *evp_md;
111 struct umac_ctx *umac_ctx;
125 u_int session_id_len;
126 Newkeys *newkeys[MODE_MAX];
140 char *client_version_string;
141 char *server_version_string;
142 int (*verify_host_key)(Key *);
143 Key *(*load_host_public_key)(int);
144 Key *(*load_host_private_key)(int);
145 int (*host_key_index)(Key *);
146 void (*sign)(Key *, Key *, u_char **, u_int *, u_char *, u_int);
147 void (*kex[KEX_MAX])(Kex *);
150 int kex_names_valid(const char *);
151 char *kex_alg_list(char);
153 #ifdef NONE_CIPHER_ENABLED
154 void kex_prop2buf(Buffer *, char *[PROPOSAL_MAX]);
157 Kex *kex_setup(char *[PROPOSAL_MAX]);
158 void kex_finish(Kex *);
160 void kex_send_kexinit(Kex *);
161 void kex_input_kexinit(int, u_int32_t, void *);
162 void kex_derive_keys(Kex *, u_char *, u_int, const u_char *, u_int);
163 void kex_derive_keys_bn(Kex *, u_char *, u_int, const BIGNUM *);
165 Newkeys *kex_get_newkeys(int);
167 void kexdh_client(Kex *);
168 void kexdh_server(Kex *);
169 void kexgex_client(Kex *);
170 void kexgex_server(Kex *);
171 void kexecdh_client(Kex *);
172 void kexecdh_server(Kex *);
173 void kexc25519_client(Kex *);
174 void kexc25519_server(Kex *);
177 kex_dh_hash(char *, char *, char *, int, char *, int, u_char *, int,
178 BIGNUM *, BIGNUM *, BIGNUM *, u_char **, u_int *);
180 kexgex_hash(int, char *, char *, char *, int, char *,
181 int, u_char *, int, int, int, int, BIGNUM *, BIGNUM *, BIGNUM *,
182 BIGNUM *, BIGNUM *, u_char **, u_int *);
183 #ifdef OPENSSL_HAS_ECC
185 kex_ecdh_hash(int, const EC_GROUP *, char *, char *, char *, int,
186 char *, int, u_char *, int, const EC_POINT *, const EC_POINT *,
187 const BIGNUM *, u_char **, u_int *);
190 kex_c25519_hash(int, char *, char *, char *, int,
191 char *, int, u_char *, int, const u_char *, const u_char *,
192 const u_char *, u_int, u_char **, u_int *);
194 #define CURVE25519_SIZE 32
195 void kexc25519_keygen(u_char[CURVE25519_SIZE], u_char[CURVE25519_SIZE])
196 __attribute__((__bounded__(__minbytes__, 1, CURVE25519_SIZE)))
197 __attribute__((__bounded__(__minbytes__, 2, CURVE25519_SIZE)));
198 void kexc25519_shared_key(const u_char key[CURVE25519_SIZE],
199 const u_char pub[CURVE25519_SIZE], Buffer *out)
200 __attribute__((__bounded__(__minbytes__, 1, CURVE25519_SIZE)))
201 __attribute__((__bounded__(__minbytes__, 2, CURVE25519_SIZE)));
204 derive_ssh1_session_id(BIGNUM *, BIGNUM *, u_int8_t[8], u_int8_t[16]);
206 #if defined(DEBUG_KEX) || defined(DEBUG_KEXDH) || defined(DEBUG_KEXECDH)
207 void dump_digest(char *, u_char *, int);