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/* $OpenBSD: kex.h,v 1.68 2015/01/19 20:07:45 markus Exp $ */
/*
* Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef KEX_H
#define KEX_H
#include "mac.h"
#include "buffer.h" /* XXX for typedef */
#include "key.h" /* XXX for typedef */
#if defined(WITH_OPENSSL) && defined(OPENSSL_HAS_ECC)
#include <openssl/ec.h>
#endif
#define KEX_COOKIE_LEN 16
#define KEX_DH1 "diffie-hellman-group1-sha1"
#define KEX_DH14 "diffie-hellman-group14-sha1"
#define KEX_DHGEX_SHA1 "diffie-hellman-group-exchange-sha1"
#define KEX_DHGEX_SHA256 "diffie-hellman-group-exchange-sha256"
#define KEX_RESUME "resume@appgate.com"
#define KEX_ECDH_SHA2_NISTP256 "ecdh-sha2-nistp256"
#define KEX_ECDH_SHA2_NISTP384 "ecdh-sha2-nistp384"
#define KEX_ECDH_SHA2_NISTP521 "ecdh-sha2-nistp521"
#define KEX_CURVE25519_SHA256 "curve25519-sha256@libssh.org"
#define COMP_NONE 0
#define COMP_ZLIB 1
#define COMP_DELAYED 2
enum kex_init_proposals {
PROPOSAL_KEX_ALGS,
PROPOSAL_SERVER_HOST_KEY_ALGS,
PROPOSAL_ENC_ALGS_CTOS,
PROPOSAL_ENC_ALGS_STOC,
PROPOSAL_MAC_ALGS_CTOS,
PROPOSAL_MAC_ALGS_STOC,
PROPOSAL_COMP_ALGS_CTOS,
PROPOSAL_COMP_ALGS_STOC,
PROPOSAL_LANG_CTOS,
PROPOSAL_LANG_STOC,
PROPOSAL_MAX
};
enum kex_modes {
MODE_IN,
MODE_OUT,
MODE_MAX
};
enum kex_exchange {
KEX_DH_GRP1_SHA1,
KEX_DH_GRP14_SHA1,
KEX_DH_GEX_SHA1,
KEX_DH_GEX_SHA256,
KEX_ECDH_SHA2,
KEX_C25519_SHA256,
KEX_MAX
};
#define KEX_INIT_SENT 0x0001
typedef struct kex Kex;
typedef struct sshcomp Comp;
typedef struct sshmac Mac;
typedef struct sshenc Enc;
typedef struct newkeys Newkeys;
struct sshenc {
char *name;
const struct sshcipher *cipher;
int enabled;
u_int key_len;
u_int iv_len;
u_int block_size;
u_char *key;
u_char *iv;
};
struct sshcomp {
u_int type;
int enabled;
char *name;
};
struct newkeys {
struct sshenc enc;
struct sshmac mac;
struct sshcomp comp;
};
struct kex {
u_char *session_id;
size_t session_id_len;
struct newkeys *newkeys[MODE_MAX];
u_int we_need;
u_int dh_need;
int server;
char *name;
int hostkey_type;
int kex_type;
int roaming;
struct sshbuf *my;
struct sshbuf *peer;
sig_atomic_t done;
int flags;
int hash_alg;
int ec_nid;
char *client_version_string;
char *server_version_string;
int (*verify_host_key)(Key *);
Key *(*load_host_public_key)(int);
Key *(*load_host_private_key)(int);
int (*host_key_index)(Key *);
void (*sign)(Key *, Key *, u_char **, u_int *, u_char *, u_int);
void (*kex[KEX_MAX])(Kex *);
};
int kex_names_valid(const char *);
char *kex_alg_list(char);
Kex *kex_setup(char *[PROPOSAL_MAX]);
void kex_finish(Kex *);
void kex_free_newkeys(struct newkeys *);
void kex_send_kexinit(Kex *);
int kex_input_kexinit(int, u_int32_t, void *);
void kex_derive_keys(Kex *, u_char *, u_int, const u_char *, u_int);
void kex_derive_keys_bn(Kex *, u_char *, u_int, const BIGNUM *);
void kexdh_client(Kex *);
void kexdh_server(Kex *);
void kexgex_client(Kex *);
void kexgex_server(Kex *);
void kexecdh_client(Kex *);
void kexecdh_server(Kex *);
void kexc25519_client(Kex *);
void kexc25519_server(Kex *);
void
kex_dh_hash(char *, char *, char *, int, char *, int, u_char *, int,
BIGNUM *, BIGNUM *, BIGNUM *, u_char **, u_int *);
void
kexgex_hash(int, char *, char *, char *, int, char *,
int, u_char *, int, int, int, int, BIGNUM *, BIGNUM *, BIGNUM *,
BIGNUM *, BIGNUM *, u_char **, u_int *);
#ifdef OPENSSL_HAS_ECC
void
kex_ecdh_hash(int, const EC_GROUP *, char *, char *, char *, int,
char *, int, u_char *, int, const EC_POINT *, const EC_POINT *,
const BIGNUM *, u_char **, u_int *);
#endif
void
kex_c25519_hash(int, char *, char *, char *, int,
char *, int, u_char *, int, const u_char *, const u_char *,
const u_char *, u_int, u_char **, u_int *);
#define CURVE25519_SIZE 32
void kexc25519_keygen(u_char[CURVE25519_SIZE], u_char[CURVE25519_SIZE])
__attribute__((__bounded__(__minbytes__, 1, CURVE25519_SIZE)))
__attribute__((__bounded__(__minbytes__, 2, CURVE25519_SIZE)));
void kexc25519_shared_key(const u_char key[CURVE25519_SIZE],
const u_char pub[CURVE25519_SIZE], Buffer *out)
__attribute__((__bounded__(__minbytes__, 1, CURVE25519_SIZE)))
__attribute__((__bounded__(__minbytes__, 2, CURVE25519_SIZE)));
void
derive_ssh1_session_id(BIGNUM *, BIGNUM *, u_int8_t[8], u_int8_t[16]);
#if defined(DEBUG_KEX) || defined(DEBUG_KEXDH) || defined(DEBUG_KEXECDH)
void dump_digest(char *, u_char *, int);
#endif
#endif
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