1 /* $OpenBSD: kex.h,v 1.47 2009/05/27 06:34:36 andreas 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 <signal.h> 30 #include <openssl/evp.h> 31 #include <openssl/hmac.h> 32 33 #define KEX_COOKIE_LEN 16 34 35 #define KEX_DH1 "diffie-hellman-group1-sha1" 36 #define KEX_DH14 "diffie-hellman-group14-sha1" 37 #define KEX_DHGEX_SHA1 "diffie-hellman-group-exchange-sha1" 38 #define KEX_DHGEX_SHA256 "diffie-hellman-group-exchange-sha256" 39 40 #define COMP_NONE 0 41 #define COMP_ZLIB 1 42 #define COMP_DELAYED 2 43 44 enum kex_init_proposals { 45 PROPOSAL_KEX_ALGS, 46 PROPOSAL_SERVER_HOST_KEY_ALGS, 47 PROPOSAL_ENC_ALGS_CTOS, 48 PROPOSAL_ENC_ALGS_STOC, 49 PROPOSAL_MAC_ALGS_CTOS, 50 PROPOSAL_MAC_ALGS_STOC, 51 PROPOSAL_COMP_ALGS_CTOS, 52 PROPOSAL_COMP_ALGS_STOC, 53 PROPOSAL_LANG_CTOS, 54 PROPOSAL_LANG_STOC, 55 PROPOSAL_MAX 56 }; 57 58 enum kex_modes { 59 MODE_IN, 60 MODE_OUT, 61 MODE_MAX 62 }; 63 64 enum kex_exchange { 65 KEX_DH_GRP1_SHA1, 66 KEX_DH_GRP14_SHA1, 67 KEX_DH_GEX_SHA1, 68 KEX_DH_GEX_SHA256, 69 KEX_MAX 70 }; 71 72 #define KEX_INIT_SENT 0x0001 73 74 typedef struct Kex Kex; 75 typedef struct Mac Mac; 76 typedef struct Comp Comp; 77 typedef struct Enc Enc; 78 typedef struct Newkeys Newkeys; 79 80 struct Enc { 81 char *name; 82 Cipher *cipher; 83 int enabled; 84 u_int key_len; 85 u_int block_size; 86 u_char *key; 87 u_char *iv; 88 }; 89 struct Mac { 90 char *name; 91 int enabled; 92 u_int mac_len; 93 u_char *key; 94 u_int key_len; 95 int type; 96 const EVP_MD *evp_md; 97 HMAC_CTX evp_ctx; 98 struct umac_ctx *umac_ctx; 99 }; 100 struct Comp { 101 int type; 102 int enabled; 103 char *name; 104 }; 105 struct Newkeys { 106 Enc enc; 107 Mac mac; 108 Comp comp; 109 }; 110 struct Kex { 111 u_char *session_id; 112 u_int session_id_len; 113 Newkeys *newkeys[MODE_MAX]; 114 u_int we_need; 115 int server; 116 char *name; 117 int hostkey_type; 118 int kex_type; 119 Buffer my; 120 Buffer peer; 121 sig_atomic_t done; 122 int flags; 123 const EVP_MD *evp_md; 124 char *client_version_string; 125 char *server_version_string; 126 int (*verify_host_key)(Key *); 127 Key *(*load_host_key)(int); 128 int (*host_key_index)(Key *); 129 void (*kex[KEX_MAX])(Kex *); 130 }; 131 132 Kex *kex_setup(char *[PROPOSAL_MAX]); 133 void kex_finish(Kex *); 134 135 void kex_send_kexinit(Kex *); 136 void kex_input_kexinit(int, u_int32_t, void *); 137 void kex_derive_keys(Kex *, u_char *, u_int, BIGNUM *); 138 139 Newkeys *kex_get_newkeys(int); 140 141 void kexdh_client(Kex *); 142 void kexdh_server(Kex *); 143 void kexgex_client(Kex *); 144 void kexgex_server(Kex *); 145 146 void 147 kex_dh_hash(char *, char *, char *, int, char *, int, u_char *, int, 148 BIGNUM *, BIGNUM *, BIGNUM *, u_char **, u_int *); 149 void 150 kexgex_hash(const EVP_MD *, char *, char *, char *, int, char *, 151 int, u_char *, int, int, int, int, BIGNUM *, BIGNUM *, BIGNUM *, 152 BIGNUM *, BIGNUM *, u_char **, u_int *); 153 154 void 155 derive_ssh1_session_id(BIGNUM *, BIGNUM *, u_int8_t[8], u_int8_t[16]); 156 157 #if defined(DEBUG_KEX) || defined(DEBUG_KEXDH) 158 void dump_digest(char *, u_char *, int); 159 #endif 160 161 #endif 162