kex.h

   1 /*      $OpenBSD: kex.h,v 1.36 2005/06/17 02:44:32 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         u_int   mac_len;
  87         u_char  *key;
  88         u_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         u_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